Avoid to parse all the expressions when the project is exported.

and some todo pass

Core/GDCore/Events/CodeGeneration/EventsCodeGenerator.cpp

@@ -658,7 +658,7 @@ gd::String EventsCodeGenerator::GenerateActionsListCode(
 }
 
 gd::String EventsCodeGenerator::GenerateParameterCodes(
-    const gd::String& parameter,
+    const gd::Expression& parameter,
     const gd::ParameterMetadata& metadata,
     gd::EventsCodeGenerationContext& context,
     const gd::String& lastObjectName,
@@ -668,19 +668,20 @@ gd::String EventsCodeGenerator::GenerateParameterCodes(
 
   if (ParameterMetadata::IsExpression("number", metadata.type)) {
     argOutput = gd::ExpressionCodeGenerator::GenerateExpressionCode(
-        *this, context, "number", parameter);
+        *this, context, "number", parameter, lastObjectName);
   } else if (ParameterMetadata::IsExpression("string", metadata.type)) {
     argOutput = gd::ExpressionCodeGenerator::GenerateExpressionCode(
-        *this, context, "string", parameter);
+        *this, context, "string", parameter, lastObjectName);
   } else if (ParameterMetadata::IsExpression("variable", metadata.type)) {
     argOutput = gd::ExpressionCodeGenerator::GenerateExpressionCode(
         *this, context, metadata.type, parameter, lastObjectName);
   } else if (ParameterMetadata::IsObject(metadata.type)) {
     // It would be possible to run a gd::ExpressionCodeGenerator if later
     // objects can have nested objects, or function returning objects.
-    argOutput = GenerateObject(parameter, metadata.type, context);
+    argOutput = GenerateObject(parameter.GetPlainString(), metadata.type, context);
   } else if (metadata.type == "relationalOperator") {
-    argOutput += parameter == "=" ? "==" : parameter;
+    auto parameterString = parameter.GetPlainString();
+    argOutput += parameterString == "=" ? "==" : parameterString;
     if (argOutput != "==" && argOutput != "<" && argOutput != ">" &&
         argOutput != "<=" && argOutput != ">=" && argOutput != "!=") {
       cout << "Warning: Bad relational operator: Set to == by default." << endl;
@@ -689,7 +690,7 @@ gd::String EventsCodeGenerator::GenerateParameterCodes(
 
     argOutput = "\"" + argOutput + "\"";
   } else if (metadata.type == "operator") {
-    argOutput += parameter;
+    argOutput += parameter.GetPlainString();
     if (argOutput != "=" && argOutput != "+" && argOutput != "-" &&
         argOutput != "/" && argOutput != "*") {
       cout << "Warning: Bad operator: Set to = by default." << endl;
@@ -698,9 +699,9 @@ gd::String EventsCodeGenerator::GenerateParameterCodes(
 
     argOutput = "\"" + argOutput + "\"";
   } else if (ParameterMetadata::IsBehavior(metadata.type)) {
-    argOutput = GenerateGetBehaviorNameCode(parameter);
+    argOutput = GenerateGetBehaviorNameCode(parameter.GetPlainString());
   } else if (metadata.type == "key") {
-    argOutput = "\"" + ConvertToString(parameter) + "\"";
+    argOutput = "\"" + ConvertToString(parameter.GetPlainString()) + "\"";
   } else if (metadata.type == "audioResource" ||
              metadata.type == "bitmapFontResource" ||
              metadata.type == "fontResource" ||
@@ -710,15 +711,17 @@ gd::String EventsCodeGenerator::GenerateParameterCodes(
              // Deprecated, old parameter names:
              metadata.type == "password" || metadata.type == "musicfile" ||
              metadata.type == "soundfile" || metadata.type == "police") {
-    argOutput = "\"" + ConvertToString(parameter) + "\"";
+    argOutput = "\"" + ConvertToString(parameter.GetPlainString()) + "\"";
   } else if (metadata.type == "mouse") {
-    argOutput = "\"" + ConvertToString(parameter) + "\"";
+    argOutput = "\"" + ConvertToString(parameter.GetPlainString()) + "\"";
   } else if (metadata.type == "yesorno") {
-    argOutput += (parameter == "yes" || parameter == "oui") ? GenerateTrue()
+    auto parameterString = parameter.GetPlainString();
+    argOutput += (parameterString == "yes" || parameterString == "oui") ? GenerateTrue()
                                                             : GenerateFalse();
   } else if (metadata.type == "trueorfalse") {
+    auto parameterString = parameter.GetPlainString();
     // This is duplicated in AdvancedExtension.cpp for GDJS
-    argOutput += (parameter == "True" || parameter == "Vrai") ? GenerateTrue()
+    argOutput += (parameterString == "True" || parameterString == "Vrai") ? GenerateTrue()
                                                               : GenerateFalse();
   }
   // Code only parameter type
@@ -738,7 +741,7 @@ gd::String EventsCodeGenerator::GenerateParameterCodes(
       if (!metadata.type.empty())
         cout << "Warning: Unknown type of parameter \"" << metadata.type
              << "\"." << std::endl;
-      argOutput += "\"" + ConvertToString(parameter) + "\"";
+      argOutput += "\"" + ConvertToString(parameter.GetPlainString()) + "\"";
     }
   }
 
@@ -758,7 +761,7 @@ vector<gd::String> EventsCodeGenerator::GenerateParametersCodes(
       parametersInfo,
       [this, &context, &supplementaryParametersTypes, &arguments](
           const gd::ParameterMetadata& parameterMetadata,
-          const gd::String& parameterValue,
+          const gd::Expression& parameterValue,
           const gd::String& lastObjectName) {
         gd::String argOutput =
             GenerateParameterCodes(parameterValue,
@@ -1243,7 +1246,7 @@ gd::String EventsCodeGenerator::GenerateArgumentsList(
   return argumentsStr;
 }
 
-EventsCodeGenerator::EventsCodeGenerator(gd::Project& project_,
+EventsCodeGenerator::EventsCodeGenerator(const gd::Project& project_,
                                          const gd::Layout& layout,
                                          const gd::Platform& platform_)
     : platform(platform_),
@@ -1260,7 +1263,7 @@ EventsCodeGenerator::EventsCodeGenerator(gd::Project& project_,
 
 EventsCodeGenerator::EventsCodeGenerator(
     const gd::Platform& platform_,
-    gd::ObjectsContainer& globalObjectsAndGroups_,
+    const gd::ObjectsContainer& globalObjectsAndGroups_,
     const gd::ObjectsContainer& objectsAndGroups_)
     : platform(platform_),
       globalObjectsAndGroups(globalObjectsAndGroups_),

Core/GDCore/Events/CodeGeneration/EventsCodeGenerator.h

@@ -48,7 +48,7 @@ class GD_CORE_API EventsCodeGenerator {
    * \brief Construct a code generator for the specified
    * platform/project/layout.
    */
-  EventsCodeGenerator(gd::Project& project_,
+  EventsCodeGenerator(const gd::Project& project_,
                       const gd::Layout& layout,
                       const gd::Platform& platform_);
 
@@ -57,7 +57,7 @@ class GD_CORE_API EventsCodeGenerator {
    * objects/groups and platform
    */
   EventsCodeGenerator(const gd::Platform& platform,
-                      gd::ObjectsContainer& globalObjectsAndGroups_,
+                      const gd::ObjectsContainer& globalObjectsAndGroups_,
                       const gd::ObjectsContainer& objectsAndGroups_);
   virtual ~EventsCodeGenerator(){};
 
@@ -327,7 +327,7 @@ class GD_CORE_API EventsCodeGenerator {
   /**
    * \brief Get the global objects/groups used for code generation.
    */
-  gd::ObjectsContainer& GetGlobalObjectsAndGroups() const {
+  const gd::ObjectsContainer& GetGlobalObjectsAndGroups() const {
     return globalObjectsAndGroups;
   }
 
@@ -348,7 +348,7 @@ class GD_CORE_API EventsCodeGenerator {
    * \brief Get the project the code is being generated for.
    * \warning This is only valid if HasProjectAndLayout() is true.
    */
-  gd::Project& GetProject() const { return *project; }
+  const gd::Project& GetProject() const { return *project; }
 
   /**
    * \brief Get the layout the code is being generated for.
@@ -517,7 +517,7 @@ class GD_CORE_API EventsCodeGenerator {
    * \endcode
    */
   virtual gd::String GenerateParameterCodes(
-      const gd::String& parameter,
+      const gd::Expression& parameter,
       const gd::ParameterMetadata& metadata,
       gd::EventsCodeGenerationContext& context,
       const gd::String& lastObjectName,
@@ -770,12 +770,12 @@ class GD_CORE_API EventsCodeGenerator {
 
   const gd::Platform& platform;  ///< The platform being used.
 
-  gd::ObjectsContainer& globalObjectsAndGroups;
+  const gd::ObjectsContainer& globalObjectsAndGroups;
   const gd::ObjectsContainer& objectsAndGroups;
 
   bool hasProjectAndLayout;  ///< true only if project and layout are valid
                              ///< references. If false, they should not be used.
-  gd::Project* project;      ///< The project being used.
+  const gd::Project* project;      ///< The project being used.
   const gd::Layout* scene;   ///< The scene being generated.
 
   bool errorOccurred;          ///< Must be set to true if an error occured.

Core/GDCore/Events/CodeGeneration/ExpressionCodeGenerator.cpp

@@ -25,36 +25,38 @@
 #include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
+#include "GDCore/IDE/Events/ExpressionTypeFinder.h"
+#include "GDCore/IDE/Events/ExpressionVariableOwnerFinder.h"
 
 namespace gd {
 
 gd::String ExpressionCodeGenerator::GenerateExpressionCode(
     EventsCodeGenerator& codeGenerator,
     EventsCodeGenerationContext& context,
-    const gd::String& type,
-    const gd::String& expression,
-    const gd::String& objectName) {
-  gd::ExpressionParser2 parser(codeGenerator.GetPlatform(),
-                               codeGenerator.GetGlobalObjectsAndGroups(),
-                               codeGenerator.GetObjectsAndGroups());
-  ExpressionCodeGenerator generator(codeGenerator, context);
+    const gd::String& rootType,
+    const gd::Expression& expression,
+    const gd::String& rootObjectName) {
+  ExpressionCodeGenerator generator(rootType, rootObjectName, codeGenerator, context);
 
-  auto node = parser.ParseExpression(type, expression, objectName);
+  auto node = expression.GetRootNode();
   if (!node) {
-    std::cout << "Error: error while parsing: \"" << expression << "\" ("
-              << type << ")" << std::endl;
+    std::cout << "Error: error while parsing: \"" << expression.GetPlainString()
+              << "\" (" << rootType << ")" << std::endl;
 
-    return generator.GenerateDefaultValue(type);
+    return generator.GenerateDefaultValue(rootType);
   }
 
-  gd::ExpressionValidator validator;
+  gd::ExpressionValidator validator(codeGenerator.GetPlatform(),
+                                    codeGenerator.GetGlobalObjectsAndGroups(),
+                                    codeGenerator.GetObjectsAndGroups(),
+                                    rootType);
   node->Visit(validator);
   if (!validator.GetErrors().empty()) {
     std::cout << "Error: \"" << validator.GetErrors()[0]->GetMessage()
-              << "\" in: \"" << expression << "\" (" << type << ")"
-              << std::endl;
+              << "\" in: \"" << expression.GetPlainString() << "\" ("
+              << rootType << ")" << std::endl;
 
-    return generator.GenerateDefaultValue(type);
+    return generator.GenerateDefaultValue(rootType);
   }
 
   node->Visit(generator);
@@ -97,15 +99,24 @@ void ExpressionCodeGenerator::OnVisitTextNode(TextNode& node) {
 void ExpressionCodeGenerator::OnVisitVariableNode(VariableNode& node) {
   // This "translation" from the type to an enum could be avoided
   // if all types were moved to an enum.
+  auto type = gd::ExpressionTypeFinder::GetType(codeGenerator.GetPlatform(),
+                                            codeGenerator.GetGlobalObjectsAndGroups(),
+                                            codeGenerator.GetObjectsAndGroups(),
+                                            rootType,
+                                            node);
   EventsCodeGenerator::VariableScope scope =
-      node.type == "globalvar"
+      type == "globalvar"
           ? gd::EventsCodeGenerator::PROJECT_VARIABLE
-          : ((node.type == "scenevar")
+          : ((type == "scenevar")
                  ? gd::EventsCodeGenerator::LAYOUT_VARIABLE
                  : gd::EventsCodeGenerator::OBJECT_VARIABLE);
-
+  auto objectName = gd::ExpressionVariableOwnerFinder::GetObjectName(codeGenerator.GetPlatform(),
+                                        codeGenerator.GetGlobalObjectsAndGroups(),
+                                        codeGenerator.GetObjectsAndGroups(),
+                                        rootObjectName,
+                                        node);
   output += codeGenerator.GenerateGetVariable(
-      node.name, scope, context, node.objectName);
+      node.name, scope, context, objectName);
   if (node.child) node.child->Visit(*this);
 }
 
@@ -117,7 +128,7 @@ void ExpressionCodeGenerator::OnVisitVariableAccessorNode(
 
 void ExpressionCodeGenerator::OnVisitVariableBracketAccessorNode(
     VariableBracketAccessorNode& node) {
-  ExpressionCodeGenerator generator(codeGenerator, context);
+  ExpressionCodeGenerator generator("string", "", codeGenerator, context);
   node.expression->Visit(generator);
   output +=
       codeGenerator.GenerateVariableBracketAccessor(generator.GetOutput());
@@ -125,39 +136,79 @@ void ExpressionCodeGenerator::OnVisitVariableBracketAccessorNode(
 }
 
 void ExpressionCodeGenerator::OnVisitIdentifierNode(IdentifierNode& node) {
-  if (gd::ParameterMetadata::IsObject(node.type)) {
+  auto type = gd::ExpressionTypeFinder::GetType(codeGenerator.GetPlatform(),
+                                            codeGenerator.GetGlobalObjectsAndGroups(),
+                                            codeGenerator.GetObjectsAndGroups(),
+                                            rootType,
+                                            node);
+  if (gd::ParameterMetadata::IsObject(type)) {
     output +=
-        codeGenerator.GenerateObject(node.identifierName, node.type, context);
-  } else {
+        codeGenerator.GenerateObject(node.identifierName, type, context);
+  } else if (gd::ParameterMetadata::IsExpression("variable", type)) {
+      EventsCodeGenerator::VariableScope scope =
+          type == "globalvar"
+              ? gd::EventsCodeGenerator::PROJECT_VARIABLE
+              : ((type == "scenevar")
+                    ? gd::EventsCodeGenerator::LAYOUT_VARIABLE
+                    : gd::EventsCodeGenerator::OBJECT_VARIABLE);
+
+      auto objectName = gd::ExpressionVariableOwnerFinder::GetObjectName(codeGenerator.GetPlatform(),
+                                            codeGenerator.GetGlobalObjectsAndGroups(),
+                                            codeGenerator.GetObjectsAndGroups(),
+                                            rootObjectName,
+                                            node);
+      output += codeGenerator.GenerateGetVariable(
+          node.identifierName, scope, context, objectName);
+      if (!node.childIdentifierName.empty()) {
+        output += codeGenerator.GenerateVariableAccessor(node.childIdentifierName);
+      }
+  } else if (node.childIdentifierName.empty()) {
     output += "/* Error during generation, unrecognized identifier type: " +
-              codeGenerator.ConvertToString(node.type) + " with value " +
+              codeGenerator.ConvertToString(type) + " with value " +
               codeGenerator.ConvertToString(node.identifierName) + " */ " +
               codeGenerator.ConvertToStringExplicit(node.identifierName);
   }
+  else {
+    // This is for function names that are put in IdentifierNode
+    // because the type is needed to tell them appart from variables.
+    output += GenerateDefaultValue(type);
+  }
 }
 
 void ExpressionCodeGenerator::OnVisitFunctionCallNode(FunctionCallNode& node) {
-  if (gd::MetadataProvider::IsBadExpressionMetadata(node.expressionMetadata)) {
+  auto type = gd::ExpressionTypeFinder::GetType(codeGenerator.GetPlatform(),
+                                            codeGenerator.GetGlobalObjectsAndGroups(),
+                                            codeGenerator.GetObjectsAndGroups(),
+                                            rootType,
+                                            node);
+
+  const gd::ExpressionMetadata &metadata = MetadataProvider::GetFunctionCallMetadata(
+      codeGenerator.GetPlatform(),
+      codeGenerator.GetGlobalObjectsAndGroups(),
+      codeGenerator.GetObjectsAndGroups(),
+      node);
+
+  if (gd::MetadataProvider::IsBadExpressionMetadata(metadata)) {
     output += "/* Error during generation, function not found: " +
               codeGenerator.ConvertToString(node.functionName) + " */ " +
-              GenerateDefaultValue(node.type);
+              GenerateDefaultValue(type);
     return;
   }
 
   if (!node.objectName.empty()) {
     if (!node.behaviorName.empty()) {
-      output += GenerateBehaviorFunctionCode(node.type,
+      output += GenerateBehaviorFunctionCode(type,
                                              node.objectName,
                                              node.behaviorName,
                                              node.parameters,
-                                             node.expressionMetadata);
+                                             metadata);
     } else {
       output += GenerateObjectFunctionCode(
-          node.type, node.objectName, node.parameters, node.expressionMetadata);
+          type, node.objectName, node.parameters, metadata);
     }
   } else {
     output +=
-        GenerateFreeFunctionCode(node.parameters, node.expressionMetadata);
+        GenerateFreeFunctionCode(node.parameters, metadata);
   }
 }
 
@@ -305,18 +356,21 @@ gd::String ExpressionCodeGenerator::GenerateParametersCodes(
 
     auto& parameterMetadata = expressionMetadata.parameters[i];
     if (!parameterMetadata.IsCodeOnly()) {
-      ExpressionCodeGenerator generator(codeGenerator, context);
       if (nonCodeOnlyParameterIndex < parameters.size()) {
+        auto objectName = gd::ExpressionVariableOwnerFinder::GetObjectName(codeGenerator.GetPlatform(),
+                                              codeGenerator.GetGlobalObjectsAndGroups(),
+                                              codeGenerator.GetObjectsAndGroups(),
+                                              rootObjectName,
+                                              *parameters[nonCodeOnlyParameterIndex].get());
+        ExpressionCodeGenerator generator(parameterMetadata.GetType(), objectName, codeGenerator, context);
         parameters[nonCodeOnlyParameterIndex]->Visit(generator);
         parametersCode += generator.GetOutput();
       } else if (parameterMetadata.IsOptional()) {
+        ExpressionCodeGenerator generator(parameterMetadata.GetType(), "", codeGenerator, context);
         // Optional parameters default value were not parsed at the time of the
         // expression parsing. Parse them now.
-        ExpressionParser2 parser(codeGenerator.GetPlatform(),
-                                 codeGenerator.GetGlobalObjectsAndGroups(),
-                                 codeGenerator.GetObjectsAndGroups());
-        auto node = parser.ParseExpression(parameterMetadata.GetType(),
-                                           parameterMetadata.GetDefaultValue());
+        ExpressionParser2 parser;
+        auto node = parser.ParseExpression(parameterMetadata.GetDefaultValue());
 
         node->Visit(generator);
         parametersCode += generator.GetOutput();
@@ -374,12 +428,22 @@ gd::String ExpressionCodeGenerator::GenerateDefaultValue(
 }
 
 void ExpressionCodeGenerator::OnVisitEmptyNode(EmptyNode& node) {
-  output += GenerateDefaultValue(node.type);
+  auto type = gd::ExpressionTypeFinder::GetType(codeGenerator.GetPlatform(),
+                                            codeGenerator.GetGlobalObjectsAndGroups(),
+                                            codeGenerator.GetObjectsAndGroups(),
+                                            rootType,
+                                            node);
+  output += GenerateDefaultValue(type);
 }
 
 void ExpressionCodeGenerator::OnVisitObjectFunctionNameNode(
     ObjectFunctionNameNode& node) {
-  output += GenerateDefaultValue(node.type);
+  auto type = gd::ExpressionTypeFinder::GetType(codeGenerator.GetPlatform(),
+                                            codeGenerator.GetGlobalObjectsAndGroups(),
+                                            codeGenerator.GetObjectsAndGroups(),
+                                            rootType,
+                                            node);
+  output += GenerateDefaultValue(type);
 }
 
 }  // namespace gd

Core/GDCore/Events/CodeGeneration/ExpressionCodeGenerator.h

@@ -9,7 +9,6 @@
 
 #include <memory>
 #include <vector>
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Events/Parsers/ExpressionParser2Node.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/String.h"
@@ -35,9 +34,11 @@ namespace gd {
  */
 class GD_CORE_API ExpressionCodeGenerator : public ExpressionParser2NodeWorker {
  public:
-  ExpressionCodeGenerator(EventsCodeGenerator& codeGenerator_,
+  ExpressionCodeGenerator(const gd::String &rootType_,
+                          const gd::String &rootObjectName_,
+                          EventsCodeGenerator& codeGenerator_,
                           EventsCodeGenerationContext& context_)
-      : codeGenerator(codeGenerator_), context(context_){};
+      : rootType(rootType_), rootObjectName(rootObjectName_), codeGenerator(codeGenerator_), context(context_){};
   virtual ~ExpressionCodeGenerator(){};
 
   /**
@@ -57,7 +58,7 @@ class GD_CORE_API ExpressionCodeGenerator : public ExpressionParser2NodeWorker {
   static gd::String GenerateExpressionCode(EventsCodeGenerator& codeGenerator,
                                            EventsCodeGenerationContext& context,
                                            const gd::String& type,
-                                           const gd::String& expression,
+                                           const gd::Expression& expression,
                                            const gd::String& objectName = "");
 
   const gd::String& GetOutput() { return output; };
@@ -103,6 +104,8 @@ class GD_CORE_API ExpressionCodeGenerator : public ExpressionParser2NodeWorker {
   gd::String output;
   EventsCodeGenerator& codeGenerator;
   EventsCodeGenerationContext& context;
+  const gd::String rootType;
+  const gd::String rootObjectName;
 };
 
 }  // namespace gd

Core/GDCore/Events/Expression.cpp

@@ -0,0 +1,41 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+
+#include "GDCore/Events/Expression.h"
+
+#include "GDCore/Events/Parsers/ExpressionParser2.h"
+#include "GDCore/String.h"
+
+namespace gd {
+
+Expression::Expression() : node(nullptr) {};
+
+Expression::Expression(gd::String plainString_)
+    : node(nullptr), plainString(plainString_) {};
+
+Expression::Expression(const char* plainString_)
+    : node(nullptr), plainString(plainString_) {};
+
+Expression::Expression(const Expression& copy)
+    : node(nullptr), plainString{copy.plainString} {};
+
+Expression& Expression::operator=(const Expression& expression) {
+  plainString = expression.plainString;
+  node = nullptr;
+  return *this;
+};
+
+Expression::~Expression(){};
+
+ExpressionNode* Expression::GetRootNode() const {
+  if (!node) {
+    gd::ExpressionParser2 parser = ExpressionParser2();
+    node = std::move(parser.ParseExpression(plainString));
+  }
+  return node.get();
+}
+
+}  // namespace gd

Core/GDCore/Events/Expression.h

@@ -6,7 +6,15 @@
 
 #ifndef GDCORE_EXPRESSION_H
 #define GDCORE_EXPRESSION_H
+
 #include "GDCore/String.h"
+#include <memory>
+
+namespace gd {
+class ExpressionParser2;
+class ObjectsContainer;
+struct ExpressionNode;
+}  // namespace gd
 
 namespace gd {
 
@@ -24,32 +32,49 @@ class GD_CORE_API Expression {
   /**
    * \brief Construct an empty expression
    */
-  Expression(){};
+  Expression();
 
   /**
    * \brief Construct an expression from a string
    */
-  Expression(gd::String plainString_) : plainString(plainString_){};
+  Expression(gd::String plainString_);
 
   /**
    * \brief Construct an expression from a const char *
    */
-  Expression(const char* plainString_) : plainString(plainString_){};
+  Expression(const char* plainString_);
+
+  /**
+   * \brief Copy construct an expression.
+   */
+  Expression(const Expression& copy);
+
+  /**
+   * \brief Expression affectation overriding.
+   */
+  Expression& operator=(const Expression& expression);
 
   /**
    * \brief Get the plain string representing the expression
    */
   inline const gd::String& GetPlainString() const { return plainString; };
 
+  /**
+   * @brief Get the expression node.
+   * @return std::unique_ptr<gd::ExpressionNode>
+   */
+  gd::ExpressionNode* GetRootNode() const;
+
   /**
    * \brief Mimics std::string::c_str
    */
   inline const char* c_str() const { return plainString.c_str(); };
 
-  virtual ~Expression(){};
+  virtual ~Expression();
 
  private:
   gd::String plainString;  ///< The expression string
+  mutable std::unique_ptr<gd::ExpressionNode> node;
 };
 
 }  // namespace gd

Core/GDCore/Events/Parsers/ExpressionParser2.cpp

@@ -26,132 +26,16 @@ namespace gd {
 
 gd::String ExpressionParser2::NAMESPACE_SEPARATOR = "::";
 
-ExpressionParser2::ExpressionParser2(
-    const gd::Platform& platform_,
-    const gd::ObjectsContainer& globalObjectsContainer_,
-    const gd::ObjectsContainer& objectsContainer_)
+ExpressionParser2::ExpressionParser2()
     : expression(""),
-      currentPosition(0),
-      platform(platform_),
-      globalObjectsContainer(globalObjectsContainer_),
-      objectsContainer(objectsContainer_) {}
-
-namespace {
-/**
- * Return the minimum number of parameters, starting from a given parameter
- * (by convention, 1 for object functions and 2 for behavior functions).
- */
-size_t GetMinimumParametersNumber(
-    const std::vector<gd::ParameterMetadata>& parameters,
-    size_t initialParameterIndex) {
-  size_t nb = 0;
-  for (std::size_t i = initialParameterIndex; i < parameters.size(); ++i) {
-    if (!parameters[i].optional && !parameters[i].codeOnly) nb++;
-  }
-
-  return nb;
-}
-
-/**
- * Return the maximum number of parameters, starting from a given parameter
- * (by convention, 1 for object functions and 2 for behavior functions).
- */
-size_t GetMaximumParametersNumber(
-    const std::vector<gd::ParameterMetadata>& parameters,
-    size_t initialParameterIndex) {
-  size_t nb = 0;
-  for (std::size_t i = initialParameterIndex; i < parameters.size(); ++i) {
-    if (!parameters[i].codeOnly) nb++;
-  }
-
-  return nb;
-}
-}  // namespace
-
-std::unique_ptr<ExpressionParserDiagnostic> ExpressionParser2::ValidateFunction(
-    const gd::String& type,
-    const gd::FunctionCallNode& function,
-    size_t functionStartPosition) {
-  if (gd::MetadataProvider::IsBadExpressionMetadata(
-          function.expressionMetadata)) {
-    return gd::make_unique<ExpressionParserError>(
-        "invalid_function_name",
-        _("Cannot find an expression with this name: ") +
-            function.functionName + "\n" +
-            _("Double check that you've not made any typo in the name."),
-        functionStartPosition,
-        GetCurrentPosition());
-  }
-
-  // Validate the type of the function
-  const gd::String& returnType = function.expressionMetadata.GetReturnType();
-  if (returnType == "number") {
-    if (type == "string")
-      return RaiseTypeError(
-          _("You tried to use an expression that returns a number, but a "
-            "string is expected. Use `ToString` if you need to convert a "
-            "number to a string."),
-          functionStartPosition);
-    else if (type != "number" && type != "number|string")
-      return RaiseTypeError(_("You tried to use an expression that returns a "
-                              "number, but another type is expected:") +
-                              " " + type,
-                            functionStartPosition);
-  } else if (returnType == "string") {
-    if (type == "number")
-      return RaiseTypeError(
-          _("You tried to use an expression that returns a string, but a "
-            "number is expected. Use `ToNumber` if you need to convert a "
-            "string to a number."),
-          functionStartPosition);
-    else if (type != "string" && type != "number|string")
-      return RaiseTypeError(_("You tried to use an expression that returns a "
-                              "string, but another type is expected:") +
-                              " " + type,
-                            functionStartPosition);
-  } else {
-    if (type != returnType)
-      return RaiseTypeError(
-          _("You tried to use an expression with the wrong return type:") + " " +
-            returnType,
-          functionStartPosition);
-  }
-
-  // Validate parameters count
-  size_t minParametersCount = GetMinimumParametersNumber(
-      function.expressionMetadata.parameters,
-      WrittenParametersFirstIndex(function.objectName, function.behaviorName));
-  size_t maxParametersCount = GetMaximumParametersNumber(
-      function.expressionMetadata.parameters,
-      WrittenParametersFirstIndex(function.objectName, function.behaviorName));
-  if (function.parameters.size() < minParametersCount ||
-      function.parameters.size() > maxParametersCount) {
-    gd::String expectedCountMessage =
-        minParametersCount == maxParametersCount
-            ? _("The number of parameters must be exactly ") +
-                  gd::String::From(minParametersCount)
-            : _("The number of parameters must be: ") +
-                  gd::String::From(minParametersCount) + "-" +
-                  gd::String::From(maxParametersCount);
-
-    if (function.parameters.size() < minParametersCount) {
-      return gd::make_unique<ExpressionParserError>(
-          "too_few_parameters",
-          "You have not entered enough parameters for the expression. " +
-              expectedCountMessage,
-          functionStartPosition,
-          GetCurrentPosition());
-    }
-  }
-
-  return gd::make_unique<ExpressionParserDiagnostic>();
-}
+      currentPosition(0) {}
 
 std::unique_ptr<TextNode> ExpressionParser2::ReadText() {
   size_t textStartPosition = GetCurrentPosition();
   SkipAllWhitespaces();
   if (!CheckIfChar(IsQuote)) {
     auto text = gd::make_unique<TextNode>("");
+	  // It can't happen.
     text->diagnostic =
         RaiseSyntaxError(_("A text must start with a double quote (\")."));
     text->location =

Core/GDCore/Events/Parsers/ExpressionParser2.h

@@ -40,9 +40,7 @@ namespace gd {
  */
 class GD_CORE_API ExpressionParser2 {
  public:
-  ExpressionParser2(const gd::Platform &platform_,
-                    const gd::ObjectsContainer &globalObjectsContainer_,
-                    const gd::ObjectsContainer &objectsContainer_);
+  ExpressionParser2();
   virtual ~ExpressionParser2(){};
 
   /**
@@ -58,13 +56,11 @@ class GD_CORE_API ExpressionParser2 {
    * \return The node representing the expression as a parsed tree.
    */
   std::unique_ptr<ExpressionNode> ParseExpression(
-      const gd::String &type,
-      const gd::String &expression_,
-      const gd::String &objectName = "") {
+      const gd::String &expression_) {
     expression = expression_;
 
     currentPosition = 0;
-    return Start(type, objectName);
+    return Start();
   }
 
   /**
@@ -88,18 +84,16 @@ class GD_CORE_API ExpressionParser2 {
    * Each method is a part of the grammar.
    */
   ///@{
-  std::unique_ptr<ExpressionNode> Start(const gd::String &type,
-                                        const gd::String &objectName = "") {
+  std::unique_ptr<ExpressionNode> Start() {
     size_t expressionStartPosition = GetCurrentPosition();
-    auto expression = Expression(type, objectName);
-
-    const gd::String &inferredType = expression->type;
+    auto expression = Expression();
 
     // Check for extra characters at the end of the expression
     if (!IsEndReached()) {
-      auto op = gd::make_unique<OperatorNode>(inferredType, ' ');
+      auto op = gd::make_unique<OperatorNode>(' ');
       op->leftHandSide = std::move(expression);
-      op->rightHandSide = ReadUntilEnd("unknown");
+      op->rightHandSide = ReadUntilEnd();
+      op->rightHandSide->parent = op.get();
 
       op->rightHandSide->diagnostic = RaiseSyntaxError(
           _("The expression has extra character at the end that should be "
@@ -113,61 +107,49 @@ class GD_CORE_API ExpressionParser2 {
     return expression;
   }
 
-  std::unique_ptr<ExpressionNode> Expression(
-      const gd::String &type, const gd::String &objectName = "") {
+  std::unique_ptr<ExpressionNode> Expression() {
     SkipAllWhitespaces();
 
     size_t expressionStartPosition = GetCurrentPosition();
-    std::unique_ptr<ExpressionNode> leftHandSide = Term(type, objectName);
-
-    const gd::String &inferredType = leftHandSide->type;
+    std::unique_ptr<ExpressionNode> leftHandSide = Term();
 
     SkipAllWhitespaces();
 
     if (IsEndReached()) return leftHandSide;
     if (CheckIfChar(IsExpressionEndingChar)) return leftHandSide;
     if (CheckIfChar(IsExpressionOperator)) {
-      auto op = gd::make_unique<OperatorNode>(inferredType, GetCurrentChar());
+      auto op = gd::make_unique<OperatorNode>(GetCurrentChar());
       op->leftHandSide = std::move(leftHandSide);
-      op->diagnostic = ValidateOperator(inferredType, GetCurrentChar());
+      op->leftHandSide->parent = op.get();
+      op->diagnostic = ValidateOperator(GetCurrentChar());
       SkipChar();
-      op->rightHandSide = Expression(inferredType, objectName);
+      op->rightHandSide = Expression();
+      op->rightHandSide->parent = op.get();
 
       op->location = ExpressionParserLocation(expressionStartPosition,
                                               GetCurrentPosition());
       return std::move(op);
     }
 
-    if (inferredType == "string") {
-      leftHandSide->diagnostic = RaiseSyntaxError(
-          "You must add the operator + between texts or expressions. For "
-          "example: \"Your name: \" + VariableString(PlayerName).");
-    } else if (inferredType == "number") {
-      leftHandSide->diagnostic = RaiseSyntaxError(
-          "No operator found. Did you forget to enter an operator (like +, -, "
-          "* or /) between numbers or expressions?");
-    } else {
-      leftHandSide->diagnostic = RaiseSyntaxError(
-          "More than one term was found. Verify that your expression is "
-          "properly written.");
-    }
+    leftHandSide->diagnostic = RaiseSyntaxError(
+        "More than one term was found. Verify that your expression is "
+        "properly written.");
 
-    auto op = gd::make_unique<OperatorNode>(inferredType, ' ');
+    auto op = gd::make_unique<OperatorNode>(' ');
     op->leftHandSide = std::move(leftHandSide);
-    op->rightHandSide = Expression(inferredType, objectName);
+    op->leftHandSide->parent = op.get();
+    op->rightHandSide = Expression();
+    op->rightHandSide->parent = op.get();
     op->location =
         ExpressionParserLocation(expressionStartPosition, GetCurrentPosition());
     return std::move(op);
   }
 
-  std::unique_ptr<ExpressionNode> Term(const gd::String &type,
-                                       const gd::String &objectName) {
+  std::unique_ptr<ExpressionNode> Term() {
     SkipAllWhitespaces();
 
     size_t expressionStartPosition = GetCurrentPosition();
-    std::unique_ptr<ExpressionNode> factor = Factor(type, objectName);
-
-    const gd::String &inferredType = factor->type;
+    std::unique_ptr<ExpressionNode> factor = Factor();
 
     SkipAllWhitespaces();
 
@@ -175,11 +157,13 @@ class GD_CORE_API ExpressionParser2 {
     // to guarantee the proper operator precedence. (Expression could also
     // be reworked to use a while loop).
     while (CheckIfChar(IsTermOperator)) {
-      auto op = gd::make_unique<OperatorNode>(inferredType, GetCurrentChar());
+      auto op = gd::make_unique<OperatorNode>(GetCurrentChar());
       op->leftHandSide = std::move(factor);
-      op->diagnostic = ValidateOperator(inferredType, GetCurrentChar());
+      op->leftHandSide->parent = op.get();
+      op->diagnostic = ValidateOperator(GetCurrentChar());
       SkipChar();
-      op->rightHandSide = Factor(inferredType, objectName);
+      op->rightHandSide = Factor();
+      op->rightHandSide->parent = op.get();
       op->location = ExpressionParserLocation(expressionStartPosition,
                                               GetCurrentPosition());
       SkipAllWhitespaces();
@@ -190,54 +174,35 @@ class GD_CORE_API ExpressionParser2 {
     return factor;
   };
 
-  std::unique_ptr<ExpressionNode> Factor(const gd::String &type,
-                                         const gd::String &objectName) {
+  std::unique_ptr<ExpressionNode> Factor() {
     SkipAllWhitespaces();
     size_t expressionStartPosition = GetCurrentPosition();
 
     if (CheckIfChar(IsQuote)) {
       std::unique_ptr<ExpressionNode> factor = ReadText();
-      if (type == "number")
-        factor->diagnostic =
-            RaiseTypeError(_("You entered a text, but a number was expected."),
-                           expressionStartPosition);
-      else if (type != "string" && type != "number|string")
-        factor->diagnostic = RaiseTypeError(
-            _("You entered a text, but this type was expected:") + type,
-            expressionStartPosition);
-
       return factor;
     } else if (CheckIfChar(IsUnaryOperator)) {
       auto unaryOperatorCharacter = GetCurrentChar();
       SkipChar();
 
-      auto operatorOperand = Factor(type, objectName);
-      const gd::String &inferredType = operatorOperand->type;
+      auto operatorOperand = Factor();
 
       auto unaryOperator = gd::make_unique<UnaryOperatorNode>(
-          inferredType, unaryOperatorCharacter);
+          unaryOperatorCharacter);
       unaryOperator->diagnostic = ValidateUnaryOperator(
-          inferredType, unaryOperatorCharacter, expressionStartPosition);
+          unaryOperatorCharacter, expressionStartPosition);
       unaryOperator->factor = std::move(operatorOperand);
+      unaryOperator->factor->parent = unaryOperator.get();
       unaryOperator->location = ExpressionParserLocation(
           expressionStartPosition, GetCurrentPosition());
 
       return std::move(unaryOperator);
     } else if (CheckIfChar(IsNumberFirstChar)) {
       std::unique_ptr<ExpressionNode> factor = ReadNumber();
-      if (type == "string")
-        factor->diagnostic = RaiseTypeError(
-            _("You entered a number, but a text was expected (in quotes)."),
-            expressionStartPosition);
-      else if (type != "number" && type != "number|string")
-        factor->diagnostic = RaiseTypeError(
-            _("You entered a number, but this type was expected:") + type,
-            expressionStartPosition);
-
       return factor;
     } else if (CheckIfChar(IsOpeningParenthesis)) {
       SkipChar();
-      std::unique_ptr<ExpressionNode> factor = SubExpression(type, objectName);
+      std::unique_ptr<ExpressionNode> factor = SubExpression();
 
       if (!CheckIfChar(IsClosingParenthesis)) {
         factor->diagnostic =
@@ -247,29 +212,20 @@ class GD_CORE_API ExpressionParser2 {
       SkipIfChar(IsClosingParenthesis);
       return factor;
     } else if (IsIdentifierAllowedChar()) {
-      // This is a place where the grammar differs according to the
-      // type being expected.
-      if (gd::ParameterMetadata::IsExpression("variable", type)) {
-        return Variable(type, objectName);
-      } else {
-        return Identifier(type);
-      }
+      return Identifier();
     }
 
-    std::unique_ptr<ExpressionNode> factor = ReadUntilWhitespace(type);
-    factor->diagnostic = RaiseEmptyError(type, expressionStartPosition);
+    std::unique_ptr<ExpressionNode> factor = ReadUntilWhitespace();
     return factor;
   }
 
-  std::unique_ptr<SubExpressionNode> SubExpression(
-      const gd::String &type, const gd::String &objectName) {
+  std::unique_ptr<SubExpressionNode> SubExpression() {
     size_t expressionStartPosition = GetCurrentPosition();
 
-    auto expression = Expression(type, objectName);
-    const gd::String &inferredType = expression->type;
+    auto expression = Expression();
 
     auto subExpression =
-        gd::make_unique<SubExpressionNode>(inferredType, std::move(expression));
+        gd::make_unique<SubExpressionNode>(std::move(expression));
     subExpression->location =
         ExpressionParserLocation(expressionStartPosition, GetCurrentPosition());
 
@@ -277,7 +233,7 @@ class GD_CORE_API ExpressionParser2 {
   };
 
   std::unique_ptr<IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode>
-  Identifier(const gd::String &type) {
+  Identifier() {
     auto identifierAndLocation = ReadIdentifierName();
     gd::String name = identifierAndLocation.name;
     auto nameLocation = identifierAndLocation.location;
@@ -304,47 +260,28 @@ class GD_CORE_API ExpressionParser2 {
 
     if (CheckIfChar(IsOpeningParenthesis)) {
       ExpressionParserLocation openingParenthesisLocation = SkipChar();
-      return FreeFunction(type, name, nameLocation, openingParenthesisLocation);
+      return FreeFunction(name, nameLocation, openingParenthesisLocation);
     } else if (CheckIfChar(IsDot)) {
       ExpressionParserLocation dotLocation = SkipChar();
       SkipAllWhitespaces();
       return ObjectFunctionOrBehaviorFunction(
-          type, name, nameLocation, dotLocation);
-    } else {
-      auto identifier = gd::make_unique<IdentifierNode>(name, type);
-      if (type == "string") {
-        identifier->diagnostic =
-            RaiseTypeError(_("You must wrap your text inside double quotes "
-                             "(example: \"Hello world\")."),
-                           nameLocation.GetStartPosition());
-      } else if (type == "number") {
-        identifier->diagnostic = RaiseTypeError(
-            _("You must enter a number."), nameLocation.GetStartPosition());
-      } else if (type == "number|string") {
-        identifier->diagnostic = RaiseTypeError(
-            _("You must enter a number or a text, wrapped inside double quotes "
-              "(example: \"Hello world\")."),
-            nameLocation.GetStartPosition());
-      } else if (!gd::ParameterMetadata::IsObject(type)) {
-        identifier->diagnostic = RaiseTypeError(
-            _("You've entered a name, but this type was expected:") + type,
-            nameLocation.GetStartPosition());
-      }
-
+          name, nameLocation, dotLocation);
+    } else if (CheckIfChar(IsOpeningSquareBracket)) {
+      return Variable(name, nameLocation);
+    }
+    else {
+      auto identifier = gd::make_unique<IdentifierNode>(name);
       identifier->location = ExpressionParserLocation(
           nameLocation.GetStartPosition(), GetCurrentPosition());
+      identifier->identifierNameLocation = identifier->location;
       return std::move(identifier);
     }
   }
 
-  std::unique_ptr<VariableNode> Variable(const gd::String &type,
-                                         const gd::String &objectName) {
-    auto identifierAndLocation = ReadIdentifierName();
-    const gd::String &name = identifierAndLocation.name;
-    const auto &nameLocation = identifierAndLocation.location;
-
-    auto variable = gd::make_unique<VariableNode>(type, name, objectName);
+  std::unique_ptr<VariableNode> Variable(const gd::String &name, gd::ExpressionParserLocation nameLocation) {
+    auto variable = gd::make_unique<VariableNode>(name);
     variable->child = VariableAccessorOrVariableBracketAccessor();
+    variable->child->parent = variable.get();
 
     variable->location = ExpressionParserLocation(
         nameLocation.GetStartPosition(), GetCurrentPosition());
@@ -359,8 +296,8 @@ class GD_CORE_API ExpressionParser2 {
     SkipAllWhitespaces();
     if (CheckIfChar(IsOpeningSquareBracket)) {
       SkipChar();
-      auto child = gd::make_unique<VariableBracketAccessorNode>(
-          Expression("number|string"));
+      auto child = gd::make_unique<VariableBracketAccessorNode>(Expression());
+      child->expression->parent = child.get();
 
       if (!CheckIfChar(IsClosingSquareBracket)) {
         child->diagnostic =
@@ -369,6 +306,7 @@ class GD_CORE_API ExpressionParser2 {
       }
       SkipIfChar(IsClosingSquareBracket);
       child->child = VariableAccessorOrVariableBracketAccessor();
+      child->child->parent = child.get();
       child->location =
           ExpressionParserLocation(childStartPosition, GetCurrentPosition());
 
@@ -381,6 +319,7 @@ class GD_CORE_API ExpressionParser2 {
       auto child =
           gd::make_unique<VariableAccessorNode>(identifierAndLocation.name);
       child->child = VariableAccessorOrVariableBracketAccessor();
+      child->child->parent = child.get();
       child->nameLocation = identifierAndLocation.location;
       child->dotLocation = dotLocation;
       child->location =
@@ -389,40 +328,21 @@ class GD_CORE_API ExpressionParser2 {
       return std::move(child);
     }
 
-    return std::move(
-        std::unique_ptr<VariableAccessorOrVariableBracketAccessorNode>());
+    return std::move(gd::make_unique<VariableAccessorOrVariableBracketAccessorNode>());
   }
 
   std::unique_ptr<FunctionCallNode> FreeFunction(
-      const gd::String &type,
       const gd::String &functionFullName,
       const ExpressionParserLocation &identifierLocation,
       const ExpressionParserLocation &openingParenthesisLocation) {
     // TODO: error if trying to use function for type != "number" && != "string"
     // + Test for it
 
-    const gd::ExpressionMetadata &metadata =
-        MetadataProvider::GetAnyExpressionMetadata(platform, functionFullName);
-
-    // In case we can't find a valid expression, ensure the node has the type
-    // that is requested by the parent, so we avoid putting "unknown" (which
-    // would be also correct, but less precise and would prevent completions to
-    // be shown to the user)
-    const gd::String returnType =
-        gd::MetadataProvider::IsBadExpressionMetadata(metadata) == true
-            ? type
-            : metadata.GetReturnType();
-
-    auto parametersNode = Parameters(metadata.parameters);
     auto function =
-        gd::make_unique<FunctionCallNode>(returnType,
-                                          std::move(parametersNode.parameters),
-                                          metadata,
-                                          functionFullName);
+        gd::make_unique<FunctionCallNode>(functionFullName);
+    auto parametersNode = Parameters(function.get());
+    function->parameters = std::move(parametersNode.parameters);
     function->diagnostic = std::move(parametersNode.diagnostic);
-    if (!function->diagnostic)  // TODO: reverse the order of diagnostic?
-      function->diagnostic = ValidateFunction(
-          type, *function, identifierLocation.GetStartPosition());
 
     function->location = ExpressionParserLocation(
         identifierLocation.GetStartPosition(), GetCurrentPosition());
@@ -434,16 +354,15 @@ class GD_CORE_API ExpressionParser2 {
     return std::move(function);
   }
 
-  std::unique_ptr<FunctionCallOrObjectFunctionNameOrEmptyNode>
+  std::unique_ptr<IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode>
   ObjectFunctionOrBehaviorFunction(
-      const gd::String &type,
-      const gd::String &objectName,
-      const ExpressionParserLocation &objectNameLocation,
-      const ExpressionParserLocation &objectNameDotLocation) {
-    auto identifierAndLocation = ReadIdentifierName();
-    const gd::String &objectFunctionOrBehaviorName = identifierAndLocation.name;
-    const auto &objectFunctionOrBehaviorNameLocation =
-        identifierAndLocation.location;
+      const gd::String &parentIdentifier,
+      const ExpressionParserLocation &parentIdentifierLocation,
+      const ExpressionParserLocation &parentIdentifierDotLocation) {
+    auto childIdentifierAndLocation = ReadIdentifierName();
+    const gd::String &childIdentifierName = childIdentifierAndLocation.name;
+    const auto &childIdentifierNameLocation =
+        childIdentifierAndLocation.location;
 
     SkipAllWhitespaces();
 
@@ -451,87 +370,68 @@ class GD_CORE_API ExpressionParser2 {
       ExpressionParserLocation namespaceSeparatorLocation =
           SkipNamespaceSeparator();
       SkipAllWhitespaces();
-      return BehaviorFunction(type,
-                              objectName,
-                              objectFunctionOrBehaviorName,
-                              objectNameLocation,
-                              objectNameDotLocation,
-                              objectFunctionOrBehaviorNameLocation,
+      return BehaviorFunction(parentIdentifier,
+                              childIdentifierName,
+                              parentIdentifierLocation,
+                              parentIdentifierDotLocation,
+                              childIdentifierNameLocation,
                               namespaceSeparatorLocation);
     } else if (CheckIfChar(IsOpeningParenthesis)) {
       ExpressionParserLocation openingParenthesisLocation = SkipChar();
 
-      gd::String objectType =
-          GetTypeOfObject(globalObjectsContainer, objectsContainer, objectName);
-
-      const gd::ExpressionMetadata &metadata =
-          MetadataProvider::GetObjectAnyExpressionMetadata(
-              platform, objectType, objectFunctionOrBehaviorName);
-
-      // In case we can't find a valid expression, ensure the node has the type
-      // that is requested by the parent, so we avoid putting "unknown" (which
-      // would be also correct, but less precise and would prevent completions
-      // to be shown to the user)
-      const gd::String returnType =
-          gd::MetadataProvider::IsBadExpressionMetadata(metadata) == true
-              ? type
-              : metadata.GetReturnType();
-
-      auto parametersNode = Parameters(metadata.parameters, objectName);
       auto function = gd::make_unique<FunctionCallNode>(
-          returnType,
-          objectName,
-          std::move(parametersNode.parameters),
-          metadata,
-          objectFunctionOrBehaviorName);
+          parentIdentifier,
+          childIdentifierName);
+      auto parametersNode = Parameters(function.get(), parentIdentifier);
+      function->parameters = std::move(parametersNode.parameters),
       function->diagnostic = std::move(parametersNode.diagnostic);
 
-      if (!function->diagnostic)  // TODO: reverse the order of diagnostic?
-        function->diagnostic = ValidateFunction(
-            type, *function, objectNameLocation.GetStartPosition());
-
-      // If the function needs a capability on the object that may not be covered
-      // by all objects, check it now.
-      if (!metadata.GetRequiredBaseObjectCapability().empty()) {
-        const gd::ObjectMetadata &objectMetadata =
-            MetadataProvider::GetObjectMetadata(platform, objectType);
-
-        if (objectMetadata.IsUnsupportedBaseObjectCapability(
-                metadata.GetRequiredBaseObjectCapability())) {
-          function->diagnostic = RaiseTypeError(
-              _("This expression exists, but it can't be used on this object."),
-              objectNameLocation.GetStartPosition());
-        }
-      }
-
       function->location = ExpressionParserLocation(
-          objectNameLocation.GetStartPosition(), GetCurrentPosition());
-      function->objectNameLocation = objectNameLocation;
-      function->objectNameDotLocation = objectNameDotLocation;
-      function->functionNameLocation = objectFunctionOrBehaviorNameLocation;
+          parentIdentifierLocation.GetStartPosition(), GetCurrentPosition());
+      function->objectNameLocation = parentIdentifierLocation;
+      function->objectNameDotLocation = parentIdentifierDotLocation;
+      function->functionNameLocation = childIdentifierNameLocation;
       function->openingParenthesisLocation = openingParenthesisLocation;
       function->closingParenthesisLocation =
           parametersNode.closingParenthesisLocation;
       return std::move(function);
+    } else if (CheckIfChar(IsDot) || CheckIfChar(IsOpeningSquareBracket)) {
+      auto variable = gd::make_unique<VariableNode>(parentIdentifier);
+      auto child =
+          gd::make_unique<VariableAccessorNode>(childIdentifierName);
+      child->child = VariableAccessorOrVariableBracketAccessor();
+      child->child->parent = child.get();
+      child->nameLocation = childIdentifierNameLocation;
+      child->dotLocation = parentIdentifierDotLocation;
+      child->location = ExpressionParserLocation(
+          parentIdentifierDotLocation.GetStartPosition(), GetCurrentPosition());
+      variable->child = std::move(child);
+      variable->child->parent = variable.get();
+
+      variable->location = ExpressionParserLocation(
+          parentIdentifierLocation.GetStartPosition(), GetCurrentPosition());
+      variable->nameLocation = parentIdentifierLocation;
+
+      return std::move(variable);
     }
 
-    auto node = gd::make_unique<ObjectFunctionNameNode>(
-        type, objectName, objectFunctionOrBehaviorName);
-    node->diagnostic = RaiseSyntaxError(
-        _("An opening parenthesis (for an object expression), or double colon "
-          "(::) was expected (for a behavior expression)."));
-
+    auto node = gd::make_unique<IdentifierNode>(
+        parentIdentifier, childIdentifierName);
+    if (!CheckIfChar(IsParameterSeparator) && !CheckIfChar(IsClosingParenthesis) && !IsEndReached()) {
+      node->diagnostic = RaiseSyntaxError(
+          _("An opening parenthesis (for an object expression), a double colon "
+            "(:: for a behavior expression), a dot or an opening bracket (for "
+            "a child variable) where expected."));
+    }
     node->location = ExpressionParserLocation(
-        objectNameLocation.GetStartPosition(), GetCurrentPosition());
-    node->objectNameLocation = objectNameLocation;
-    node->objectNameDotLocation = objectNameDotLocation;
-    node->objectFunctionOrBehaviorNameLocation =
-        objectFunctionOrBehaviorNameLocation;
+        parentIdentifierLocation.GetStartPosition(), GetCurrentPosition());
+    node->identifierNameLocation = parentIdentifierLocation;
+    node->identifierNameDotLocation = parentIdentifierDotLocation;
+    node->childIdentifierNameLocation = childIdentifierNameLocation;
     return std::move(node);
   }
 
   std::unique_ptr<FunctionCallOrObjectFunctionNameOrEmptyNode> BehaviorFunction(
-      const gd::String &type,
       const gd::String &objectName,
       const gd::String &behaviorName,
       const ExpressionParserLocation &objectNameLocation,
@@ -547,35 +447,14 @@ class GD_CORE_API ExpressionParser2 {
     if (CheckIfChar(IsOpeningParenthesis)) {
       ExpressionParserLocation openingParenthesisLocation = SkipChar();
 
-      gd::String behaviorType = GetTypeOfBehavior(
-          globalObjectsContainer, objectsContainer, behaviorName);
-
-      const gd::ExpressionMetadata &metadata =
-          MetadataProvider::GetBehaviorAnyExpressionMetadata(
-              platform, behaviorType, functionName);
-
-      // In case we can't find a valid expression, ensure the node has the type
-      // that is requested by the parent, so we avoid putting "unknown" (which
-      // would be also correct, but less precise and would prevent completions
-      // to be shown to the user)
-      const gd::String returnType =
-          gd::MetadataProvider::IsBadExpressionMetadata(metadata) == true
-              ? type
-              : metadata.GetReturnType();
-
-      auto parametersNode =
-          Parameters(metadata.parameters, objectName, behaviorName);
       auto function = gd::make_unique<FunctionCallNode>(
-          returnType,
           objectName,
           behaviorName,
-          std::move(parametersNode.parameters),
-          metadata,
           functionName);
+      auto parametersNode =
+          Parameters(function.get(), objectName, behaviorName);
+      function->parameters = std::move(parametersNode.parameters);
       function->diagnostic = std::move(parametersNode.diagnostic);
-      if (!function->diagnostic)  // TODO: reverse the order of diagnostic?
-        function->diagnostic = ValidateFunction(
-            type, *function, objectNameLocation.GetStartPosition());
 
       function->location = ExpressionParserLocation(
           objectNameLocation.GetStartPosition(), GetCurrentPosition());
@@ -591,7 +470,7 @@ class GD_CORE_API ExpressionParser2 {
       return std::move(function);
     } else {
       auto node = gd::make_unique<ObjectFunctionNameNode>(
-          type, objectName, behaviorName, functionName);
+          objectName, behaviorName, functionName);
       node->diagnostic = RaiseSyntaxError(
           _("An opening parenthesis was expected here to call a function."));
 
@@ -615,7 +494,7 @@ class GD_CORE_API ExpressionParser2 {
   };
 
   ParametersNode Parameters(
-      std::vector<gd::ParameterMetadata> parameterMetadata,
+      FunctionCallNode *functionCallNode,
       const gd::String &objectName = "",
       const gd::String &behaviorName = "") {
     std::vector<std::unique_ptr<ExpressionNode>> parameters;
@@ -626,77 +505,25 @@ class GD_CORE_API ExpressionParser2 {
     size_t parameterIndex =
         WrittenParametersFirstIndex(objectName, behaviorName);
 
+    bool previousCharacterIsParameterSeparator = false;
     while (!IsEndReached()) {
       SkipAllWhitespaces();
 
-      if (CheckIfChar(IsClosingParenthesis)) {
+      if (CheckIfChar(IsClosingParenthesis) && !previousCharacterIsParameterSeparator) {
         auto closingParenthesisLocation = SkipChar();
         return ParametersNode{
             std::move(parameters), nullptr, closingParenthesisLocation};
-      } else {
-        if (parameterIndex < parameterMetadata.size()) {
-          const gd::String &type = parameterMetadata[parameterIndex].GetType();
-          if (parameterMetadata[parameterIndex].IsCodeOnly()) {
-            // Do nothing, code only parameters are not written in expressions.
-          } else if (gd::ParameterMetadata::IsExpression("number", type)) {
-            parameters.push_back(Expression("number"));
-          } else if (gd::ParameterMetadata::IsExpression("string", type)) {
-            parameters.push_back(Expression("string"));
-          } else if (gd::ParameterMetadata::IsExpression("variable", type)) {
-            parameters.push_back(Expression(
-                type, lastObjectName.empty() ? objectName : lastObjectName));
-          } else if (gd::ParameterMetadata::IsObject(type)) {
-            size_t parameterStartPosition = GetCurrentPosition();
-            std::unique_ptr<ExpressionNode> objectExpression = Expression(type);
-
-            // Memorize the last object name. By convention, parameters that
-            // require an object (mainly, "objectvar" and "behavior") should be
-            // placed after the object in the list of parameters (if possible,
-            // just after). Search "lastObjectName" in the codebase for other
-            // place where this convention is enforced.
-            if (auto identifierNode =
-                    dynamic_cast<IdentifierNode *>(objectExpression.get())) {
-              lastObjectName = identifierNode->identifierName;
-            } else {
-              objectExpression->diagnostic =
-                  gd::make_unique<ExpressionParserError>(
-                      "malformed_object_parameter",
-                      _("An object name was expected but something else was "
-                        "written. Enter just the name of the object for this "
-                        "parameter."),
-                      parameterStartPosition,
-                      GetCurrentPosition());
-            }
-
-            parameters.push_back(std::move(objectExpression));
-          } else {
-            size_t parameterStartPosition = GetCurrentPosition();
-            parameters.push_back(Expression("unknown"));
-            parameters.back()->diagnostic =
-                gd::make_unique<ExpressionParserError>(
-                    "unknown_parameter_type",
-                    _("This function is improperly set up. Reach out to the "
-                      "extension developer or a GDevelop maintainer to fix "
-                      "this issue"),
-                    parameterStartPosition,
-                    GetCurrentPosition());
-          }
-        } else {
-          size_t parameterStartPosition = GetCurrentPosition();
-          parameters.push_back(Expression("unknown"));
-          parameters.back()
-              ->diagnostic = gd::make_unique<ExpressionParserError>(
-              "extra_parameter",
-              _("This parameter was not expected by this expression. Remove it "
-                "or verify that you've entered the proper expression name."),
-              parameterStartPosition,
-              GetCurrentPosition());
-        }
-
-        SkipAllWhitespaces();
-        SkipIfChar(IsParameterSeparator);
-        parameterIndex++;
       }
+      bool isEmptyParameter = CheckIfChar(IsParameterSeparator)
+          || (CheckIfChar(IsClosingParenthesis) && previousCharacterIsParameterSeparator);
+      auto parameter = isEmptyParameter ? gd::make_unique<EmptyNode>() : Expression();
+      parameter->parent = functionCallNode;
+      parameters.push_back(std::move(parameter));
+
+      SkipAllWhitespaces();
+      previousCharacterIsParameterSeparator = CheckIfChar(IsParameterSeparator);
+      SkipIfChar(IsParameterSeparator);
+      parameterIndex++;
     }
 
     ExpressionParserLocation invalidClosingParenthesisLocation;
@@ -708,92 +535,32 @@ class GD_CORE_API ExpressionParser2 {
   }
   ///@}
 
-  /** \name Validators
-   * Return a diagnostic if any error is found
-   */
-  ///@{
-  std::unique_ptr<ExpressionParserDiagnostic> ValidateFunction(
-      const gd::String &type,
-      const gd::FunctionCallNode &function,
-      size_t functionStartPosition);
-
   std::unique_ptr<ExpressionParserDiagnostic> ValidateOperator(
-      const gd::String &type, gd::String::value_type operatorChar) {
-    if (type == "number") {
-      if (operatorChar == '+' || operatorChar == '-' || operatorChar == '/' ||
-          operatorChar == '*') {
-        return gd::make_unique<ExpressionParserDiagnostic>();
-      }
-
-      return gd::make_unique<ExpressionParserError>(
-          "invalid_operator",
-          _("You've used an operator that is not supported. Operator should be "
-            "either +, -, / or *."),
-          GetCurrentPosition());
-    } else if (type == "string") {
-      if (operatorChar == '+') {
-        return gd::make_unique<ExpressionParserDiagnostic>();
-      }
-
-      return gd::make_unique<ExpressionParserError>(
-          "invalid_operator",
-          _("You've used an operator that is not supported. Only + can be used "
-            "to concatenate texts."),
-          GetCurrentPosition());
-    } else if (gd::ParameterMetadata::IsObject(type)) {
-      return gd::make_unique<ExpressionParserError>(
-          "invalid_operator",
-          _("Operators (+, -, /, *) can't be used with an object name. Remove "
-            "the operator."),
-          GetCurrentPosition());
-    } else if (gd::ParameterMetadata::IsExpression("variable", type)) {
-      return gd::make_unique<ExpressionParserError>(
-          "invalid_operator",
-          _("Operators (+, -, /, *) can't be used in variable names. Remove "
-            "the operator from the variable name."),
-          GetCurrentPosition());
+      gd::String::value_type operatorChar) {
+    if (operatorChar == '+' || operatorChar == '-' || operatorChar == '/' ||
+        operatorChar == '*') {
+      return gd::make_unique<ExpressionParserDiagnostic>();
     }
-
-    return gd::make_unique<ExpressionParserDiagnostic>();
+    return gd::make_unique<ExpressionParserError>(
+        "invalid_operator",
+        _("You've used an operator that is not supported. Operator should be "
+          "either +, -, / or *."),
+        GetCurrentPosition());
   }
 
   std::unique_ptr<ExpressionParserDiagnostic> ValidateUnaryOperator(
-      const gd::String &type,
       gd::String::value_type operatorChar,
       size_t position) {
-    if (type == "number") {
-      if (operatorChar == '+' || operatorChar == '-') {
-        return gd::make_unique<ExpressionParserDiagnostic>();
-      }
-
-      return gd::make_unique<ExpressionParserError>(
-          "invalid_operator",
-          _("You've used an \"unary\" operator that is not supported. Operator "
-            "should be "
-            "either + or -."),
-          position);
-    } else if (type == "string") {
-      return gd::make_unique<ExpressionParserError>(
-          "invalid_operator",
-          _("You've used an operator that is not supported. Only + can be used "
-            "to concatenate texts, and must be placed between two texts (or "
-            "expressions)."),
-          position);
-    } else if (gd::ParameterMetadata::IsObject(type)) {
-      return gd::make_unique<ExpressionParserError>(
-          "invalid_operator",
-          _("Operators (+, -) can't be used with an object name. Remove the "
-            "operator."),
-          position);
-    } else if (gd::ParameterMetadata::IsExpression("variable", type)) {
-      return gd::make_unique<ExpressionParserError>(
-          "invalid_operator",
-          _("Operators (+, -) can't be used in variable names. Remove "
-            "the operator from the variable name."),
-          position);
+    if (operatorChar == '+' || operatorChar == '-') {
+      return gd::make_unique<ExpressionParserDiagnostic>();
     }
 
-    return gd::make_unique<ExpressionParserDiagnostic>();
+    return gd::make_unique<ExpressionParserError>(
+        "invalid_operator",
+        _("You've used an \"unary\" operator that is not supported. Operator "
+          "should be "
+          "either + or -."),
+        position);
   }
   ///@}
 
@@ -981,7 +748,7 @@ class GD_CORE_API ExpressionParser2 {
 
   std::unique_ptr<NumberNode> ReadNumber();
 
-  std::unique_ptr<EmptyNode> ReadUntilWhitespace(gd::String type) {
+  std::unique_ptr<EmptyNode> ReadUntilWhitespace() {
     size_t startPosition = GetCurrentPosition();
     gd::String text;
     while (currentPosition < expression.size() &&
@@ -990,13 +757,13 @@ class GD_CORE_API ExpressionParser2 {
       currentPosition++;
     }
 
-    auto node = gd::make_unique<EmptyNode>(type, text);
+    auto node = gd::make_unique<EmptyNode>(text);
     node->location =
         ExpressionParserLocation(startPosition, GetCurrentPosition());
     return node;
   }
 
-  std::unique_ptr<EmptyNode> ReadUntilEnd(gd::String type) {
+  std::unique_ptr<EmptyNode> ReadUntilEnd() {
     size_t startPosition = GetCurrentPosition();
     gd::String text;
     while (currentPosition < expression.size()) {
@@ -1004,7 +771,7 @@ class GD_CORE_API ExpressionParser2 {
       currentPosition++;
     }
 
-    auto node = gd::make_unique<EmptyNode>(type, text);
+    auto node = gd::make_unique<EmptyNode>(text);
     node->location =
         ExpressionParserLocation(startPosition, GetCurrentPosition());
     return node;
@@ -1037,34 +804,11 @@ class GD_CORE_API ExpressionParser2 {
     return std::move(gd::make_unique<ExpressionParserError>(
         "type_error", message, beginningPosition, GetCurrentPosition()));
   }
-
-  std::unique_ptr<ExpressionParserError> RaiseEmptyError(
-      const gd::String &type, size_t beginningPosition) {
-    gd::String message;
-    if (type == "number") {
-      message = _("You must enter a number or a valid expression call.");
-    } else if (type == "string") {
-      message = _(
-          "You must enter a text (between quotes) or a valid expression call.");
-    } else if (gd::ParameterMetadata::IsExpression("variable", type)) {
-      message = _("You must enter a variable name.");
-    } else if (gd::ParameterMetadata::IsObject(type)) {
-      message = _("You must enter a valid object name.");
-    } else {
-      message = _("You must enter a valid expression.");
-    }
-
-    return std::move(RaiseTypeError(message, beginningPosition));
-  }
   ///@}
 
   gd::String expression;
   std::size_t currentPosition;
 
-  const gd::Platform &platform;
-  const gd::ObjectsContainer &globalObjectsContainer;
-  const gd::ObjectsContainer &objectsContainer;
-
   static gd::String NAMESPACE_SEPARATOR;
 };
 

Core/GDCore/Events/Parsers/ExpressionParser2Node.h

@@ -17,6 +17,7 @@ class ObjectsContainer;
 class Platform;
 class ParameterMetadata;
 class ExpressionMetadata;
+struct FunctionCallNode;
 }  // namespace gd
 
 namespace gd {
@@ -57,6 +58,10 @@ struct GD_CORE_API ExpressionParserDiagnostic {
  * \brief An error that can be attached to a gd::ExpressionNode.
  */
 struct GD_CORE_API ExpressionParserError : public ExpressionParserDiagnostic {
+  ExpressionParserError(const gd::String &type_,
+                        const gd::String &message_,
+                        const ExpressionParserLocation &location_)
+      : type(type_), message(message_), location(location_){};
   ExpressionParserError(const gd::String &type_,
                         const gd::String &message_,
                         size_t position_)
@@ -86,7 +91,7 @@ struct GD_CORE_API ExpressionParserError : public ExpressionParserDiagnostic {
  * an expression inherits from.
  */
 struct GD_CORE_API ExpressionNode {
-  ExpressionNode(const gd::String &type_) : type(type_){};
+  ExpressionNode() : parent(nullptr) {};
   virtual ~ExpressionNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker){};
 
@@ -97,17 +102,12 @@ struct GD_CORE_API ExpressionNode {
                                       /// function can store the position of the
                                       /// object name, the dot, the function
                                       /// name, etc...
-
-  gd::String type;  // Actual type of the node.
-                    // "string", "number", type supported by
-                    // gd::ParameterMetadata::IsObject, types supported by
-                    // gd::ParameterMetadata::IsExpression or "unknown".
+  ExpressionNode *parent;
 };
 
 struct GD_CORE_API SubExpressionNode : public ExpressionNode {
-  SubExpressionNode(const gd::String &type_,
-                    std::unique_ptr<ExpressionNode> expression_)
-      : ExpressionNode(type_), expression(std::move(expression_)){};
+  SubExpressionNode(std::unique_ptr<ExpressionNode> expression_)
+      : ExpressionNode(), expression(std::move(expression_)){};
   virtual ~SubExpressionNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitSubExpressionNode(*this);
@@ -120,8 +120,8 @@ struct GD_CORE_API SubExpressionNode : public ExpressionNode {
  * \brief An operator node. For example: "lhs + rhs".
  */
 struct GD_CORE_API OperatorNode : public ExpressionNode {
-  OperatorNode(const gd::String &type_, gd::String::value_type op_)
-      : ExpressionNode(type_), op(op_){};
+  OperatorNode(gd::String::value_type op_)
+      : ExpressionNode(), op(op_){};
   virtual ~OperatorNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitOperatorNode(*this);
@@ -136,8 +136,8 @@ struct GD_CORE_API OperatorNode : public ExpressionNode {
  * \brief A unary operator node. For example: "-2".
  */
 struct GD_CORE_API UnaryOperatorNode : public ExpressionNode {
-  UnaryOperatorNode(const gd::String &type_, gd::String::value_type op_)
-      : ExpressionNode(type_), op(op_){};
+  UnaryOperatorNode(gd::String::value_type op_)
+      : ExpressionNode(), op(op_){};
   virtual ~UnaryOperatorNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitUnaryOperatorNode(*this);
@@ -153,7 +153,7 @@ struct GD_CORE_API UnaryOperatorNode : public ExpressionNode {
  */
 struct GD_CORE_API NumberNode : public ExpressionNode {
   NumberNode(const gd::String &number_)
-      : ExpressionNode("number"), number(number_){};
+      : ExpressionNode(), number(number_){};
   virtual ~NumberNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitNumberNode(*this);
@@ -168,7 +168,7 @@ struct GD_CORE_API NumberNode : public ExpressionNode {
  * Its `type` is always "string".
  */
 struct GD_CORE_API TextNode : public ExpressionNode {
-  TextNode(const gd::String &text_) : ExpressionNode("string"), text(text_){};
+  TextNode(const gd::String &text_) : ExpressionNode(), text(text_){};
   virtual ~TextNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitTextNode(*this);
@@ -177,32 +177,88 @@ struct GD_CORE_API TextNode : public ExpressionNode {
   gd::String text;
 };
 
+struct GD_CORE_API IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode
+    : public ExpressionNode {
+  IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode()
+      : ExpressionNode(){};
+};
+
+/**
+ * \brief An identifier node, usually representing an object or a variable
+ * with an optional function name or child variable name respectively.
+ *
+ * The name of a function to call on an object or the behavior,
+ * for example: "MyObject.Function" or "MyObject.Physics".
+ * 
+ * A variable, potentially with accessor to its child,
+ * for example: MyVariable or MyVariable.MyChild
+ */
+struct GD_CORE_API IdentifierNode
+    : public IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode {
+  IdentifierNode(
+  const gd::String &identifierName_)
+      : IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode(),
+        identifierName(identifierName_),
+        childIdentifierName(""){};
+  IdentifierNode(
+  const gd::String &identifierName_,
+  const gd::String &childIdentifierName_)
+      : IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode(),
+        identifierName(identifierName_),
+        childIdentifierName(childIdentifierName_){};
+  virtual ~IdentifierNode(){};
+  virtual void Visit(ExpressionParser2NodeWorker &worker) {
+    worker.OnVisitIdentifierNode(*this);
+  };
+
+  gd::String identifierName;  ///< The object or variable name.
+  gd::String childIdentifierName;  ///< The object function or variable child name.
+
+
+  ExpressionParserLocation
+      identifierNameLocation;  ///< Location of the object or variable name.
+  ExpressionParserLocation
+      identifierNameDotLocation;  ///< Location of the "." after the object or variable name.
+  ExpressionParserLocation childIdentifierNameLocation;  ///< Location of object
+                                                         /// function, behavior or
+                                                         /// child variable name.
+};
+
+struct GD_CORE_API FunctionCallOrObjectFunctionNameOrEmptyNode
+    : public IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode {
+  FunctionCallOrObjectFunctionNameOrEmptyNode()
+      : IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode(){};
+  virtual ~FunctionCallOrObjectFunctionNameOrEmptyNode(){};
+  void Visit(ExpressionParser2NodeWorker &worker) override{};
+};
+
 struct GD_CORE_API VariableAccessorOrVariableBracketAccessorNode : public ExpressionNode {
-  VariableAccessorOrVariableBracketAccessorNode() : ExpressionNode(""){};
+  VariableAccessorOrVariableBracketAccessorNode() : ExpressionNode(){};
 
   std::unique_ptr<VariableAccessorOrVariableBracketAccessorNode> child;
 };
 
 /**
- * \brief A variable, potentially with accessor to its children.
- *
- * Example: MyVariable or MyVariable.MyChildren
+ * \brief A variable with bracket accessor or at least 2 "dot" accessors.
  *
+ * Example: MyVariable[MyChildren] or MyVariable.MyChildren.MyGranChildren.
+ * 
+ * Other cases like "MyVariable" or "MyVariable.MyChildren" are IdentifierNode
+ * to allow handling ambiguities.
+ * 
+ * \see gd::IdentifierNode
  * \see gd::VariableAccessorNode
  * \see gd::VariableBracketAccessorNode
  */
-struct GD_CORE_API VariableNode : public ExpressionNode {
-  VariableNode(const gd::String &type_,
-               const gd::String &name_,
-               const gd::String &objectName_)
-      : ExpressionNode(type_), name(name_), objectName(objectName_){};
+struct GD_CORE_API VariableNode : public FunctionCallOrObjectFunctionNameOrEmptyNode {
+  VariableNode(const gd::String &name_)
+      : FunctionCallOrObjectFunctionNameOrEmptyNode(), name(name_){};
   virtual ~VariableNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitVariableNode(*this);
   };
 
   gd::String name;
-  gd::String objectName;
 
   std::unique_ptr<VariableAccessorOrVariableBracketAccessorNode>
       child;  // Can be nullptr if no accessor
@@ -216,7 +272,8 @@ struct GD_CORE_API VariableNode : public ExpressionNode {
  */
 struct GD_CORE_API VariableAccessorNode
     : public VariableAccessorOrVariableBracketAccessorNode {
-  VariableAccessorNode(const gd::String &name_) : name(name_){};
+  VariableAccessorNode(const gd::String &name_)
+      : VariableAccessorOrVariableBracketAccessorNode(), name(name_){};
   virtual ~VariableAccessorNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitVariableAccessorNode(*this);
@@ -234,7 +291,7 @@ struct GD_CORE_API VariableAccessorNode
 struct GD_CORE_API VariableBracketAccessorNode
     : public VariableAccessorOrVariableBracketAccessorNode {
   VariableBracketAccessorNode(std::unique_ptr<ExpressionNode> expression_)
-      : expression(std::move(expression_)){};
+      : VariableAccessorOrVariableBracketAccessorNode(), expression(std::move(expression_)){};
   virtual ~VariableBracketAccessorNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitVariableBracketAccessorNode(*this);
@@ -243,55 +300,26 @@ struct GD_CORE_API VariableBracketAccessorNode
   std::unique_ptr<ExpressionNode> expression;
 };
 
-struct GD_CORE_API IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode
-    : public ExpressionNode {
-  IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode(
-      const gd::String &type)
-      : ExpressionNode(type){};
-};
-
-/**
- * \brief An identifier node, usually representing an object or a function name.
- */
-struct GD_CORE_API IdentifierNode
-    : public IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode {
-  IdentifierNode(const gd::String &identifierName_, const gd::String &type_)
-      : IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode(type_),
-        identifierName(identifierName_){};
-  virtual ~IdentifierNode(){};
-  virtual void Visit(ExpressionParser2NodeWorker &worker) {
-    worker.OnVisitIdentifierNode(*this);
-  };
-
-  gd::String identifierName;
-};
-
-struct GD_CORE_API FunctionCallOrObjectFunctionNameOrEmptyNode
-    : public IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode {
-  FunctionCallOrObjectFunctionNameOrEmptyNode(const gd::String &type)
-      : IdentifierOrFunctionCallOrObjectFunctionNameOrEmptyNode(type){};
-  virtual ~FunctionCallOrObjectFunctionNameOrEmptyNode(){};
-  void Visit(ExpressionParser2NodeWorker &worker) override{};
-};
-
 /**
  * \brief The name of a function to call on an object or the behavior
- * For example: "MyObject.Function" or "MyObject.Physics" or
- * "MyObject.Physics::LinearVelocity".
+ * For example: "MyObject.Physics::LinearVelocity".
+ * 
+ * Other cases like "MyObject.Function" or "MyObject.Physics" are IdentifierNode
+ * to allow handling ambiguities.
+ * 
+ * \see gd::IdentifierNode
  */
 struct GD_CORE_API ObjectFunctionNameNode
     : public FunctionCallOrObjectFunctionNameOrEmptyNode {
-  ObjectFunctionNameNode(const gd::String &type_,
-                         const gd::String &objectName_,
+  ObjectFunctionNameNode(const gd::String &objectName_,
                          const gd::String &objectFunctionOrBehaviorName_)
-      : FunctionCallOrObjectFunctionNameOrEmptyNode(type_),
+      : FunctionCallOrObjectFunctionNameOrEmptyNode(),
         objectName(objectName_),
         objectFunctionOrBehaviorName(objectFunctionOrBehaviorName_) {}
-  ObjectFunctionNameNode(const gd::String &type_,
-                         const gd::String &objectName_,
+  ObjectFunctionNameNode(const gd::String &objectName_,
                          const gd::String &behaviorName_,
                          const gd::String &behaviorFunctionName_)
-      : FunctionCallOrObjectFunctionNameOrEmptyNode(type_),
+      : FunctionCallOrObjectFunctionNameOrEmptyNode(),
         objectName(objectName_),
         objectFunctionOrBehaviorName(behaviorName_),
         behaviorFunctionName(behaviorFunctionName_) {}
@@ -334,39 +362,24 @@ struct GD_CORE_API ObjectFunctionNameNode
  */
 struct GD_CORE_API FunctionCallNode : public FunctionCallOrObjectFunctionNameOrEmptyNode {
   /** \brief Construct a free function call node. */
-  FunctionCallNode(const gd::String &type_,
-                   std::vector<std::unique_ptr<ExpressionNode>> parameters_,
-                   const ExpressionMetadata &expressionMetadata_,
-                   const gd::String &functionName_)
-      : FunctionCallOrObjectFunctionNameOrEmptyNode(type_),
-        parameters(std::move(parameters_)),
-        expressionMetadata(expressionMetadata_),
+  FunctionCallNode(const gd::String &functionName_)
+      : FunctionCallOrObjectFunctionNameOrEmptyNode(),
         functionName(functionName_){};
 
   /** \brief Construct an object function call node. */
-  FunctionCallNode(const gd::String &type_,
-                   const gd::String &objectName_,
-                   std::vector<std::unique_ptr<ExpressionNode>> parameters_,
-                   const ExpressionMetadata &expressionMetadata_,
+  FunctionCallNode(const gd::String &objectName_,
                    const gd::String &functionName_)
-      : FunctionCallOrObjectFunctionNameOrEmptyNode(type_),
+      : FunctionCallOrObjectFunctionNameOrEmptyNode(),
         objectName(objectName_),
-        parameters(std::move(parameters_)),
-        expressionMetadata(expressionMetadata_),
         functionName(functionName_){};
 
   /** \brief Construct a behavior function call node. */
-  FunctionCallNode(const gd::String &type_,
-                   const gd::String &objectName_,
+  FunctionCallNode(const gd::String &objectName_,
                    const gd::String &behaviorName_,
-                   std::vector<std::unique_ptr<ExpressionNode>> parameters_,
-                   const ExpressionMetadata &expressionMetadata_,
                    const gd::String &functionName_)
-      : FunctionCallOrObjectFunctionNameOrEmptyNode(type_),
+      : FunctionCallOrObjectFunctionNameOrEmptyNode(),
         objectName(objectName_),
         behaviorName(behaviorName_),
-        parameters(std::move(parameters_)),
-        expressionMetadata(expressionMetadata_),
         functionName(functionName_){};
   virtual ~FunctionCallNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
@@ -376,7 +389,6 @@ struct GD_CORE_API FunctionCallNode : public FunctionCallOrObjectFunctionNameOrE
   gd::String objectName;
   gd::String behaviorName;
   std::vector<std::unique_ptr<ExpressionNode>> parameters;
-  const ExpressionMetadata &expressionMetadata;
   gd::String functionName;
 
   ExpressionParserLocation
@@ -401,8 +413,8 @@ struct GD_CORE_API FunctionCallNode : public FunctionCallOrObjectFunctionNameOrE
  * encountered and any other node could not make sense.
  */
 struct GD_CORE_API EmptyNode : public FunctionCallOrObjectFunctionNameOrEmptyNode {
-  EmptyNode(const gd::String &type_, const gd::String &text_ = "")
-      : FunctionCallOrObjectFunctionNameOrEmptyNode(type_), text(text_){};
+  EmptyNode(const gd::String &text_ = "")
+      : FunctionCallOrObjectFunctionNameOrEmptyNode(), text(text_){};
   virtual ~EmptyNode(){};
   virtual void Visit(ExpressionParser2NodeWorker &worker) {
     worker.OnVisitEmptyNode(*this);

Core/GDCore/Events/Parsers/ExpressionParser2NodePrinter.h

@@ -91,6 +91,9 @@ class GD_CORE_API ExpressionParser2NodePrinter
   }
   void OnVisitIdentifierNode(IdentifierNode& node) override {
     output += node.identifierName;
+    if (!node.childIdentifierName.empty()) {
+      output += "." + node.childIdentifierName;
+    }
   }
   void OnVisitObjectFunctionNameNode(ObjectFunctionNameNode& node) override {
     if (!node.behaviorFunctionName.empty()) {

Core/GDCore/Extensions/Metadata/MetadataProvider.cpp

@@ -13,7 +13,9 @@
 #include "GDCore/Extensions/Metadata/ObjectMetadata.h"
 #include "GDCore/Extensions/Platform.h"
 #include "GDCore/Extensions/PlatformExtension.h"
+#include "GDCore/Project/Layout.h"  // For GetTypeOfObject and GetTypeOfBehavior
 #include "GDCore/String.h"
+#include "GDCore/Events/Parsers/ExpressionParser2.h"
 
 using namespace std;
 
@@ -30,12 +32,9 @@ ExtensionAndMetadata<BehaviorMetadata>
 MetadataProvider::GetExtensionAndBehaviorMetadata(const gd::Platform& platform,
                                                   gd::String behaviorType) {
   for (auto& extension : platform.GetAllPlatformExtensions()) {
-    auto behaviorTypes = extension->GetBehaviorsTypes();
-    for (std::size_t j = 0; j < behaviorTypes.size(); ++j) {
-      if (behaviorTypes[j] == behaviorType)
-        return ExtensionAndMetadata<BehaviorMetadata>(
-            *extension, extension->GetBehaviorMetadata(behaviorType));
-    }
+    if (extension->HasBehavior(behaviorType))
+      return ExtensionAndMetadata<BehaviorMetadata>(
+          *extension, extension->GetBehaviorMetadata(behaviorType));
   }
 
   return ExtensionAndMetadata<BehaviorMetadata>(badExtension, badBehaviorMetadata);
@@ -202,8 +201,7 @@ MetadataProvider::GetExtensionAndBehaviorExpressionMetadata(
     const gd::Platform& platform, gd::String autoType, gd::String exprType) {
   auto& extensions = platform.GetAllPlatformExtensions();
   for (auto& extension : extensions) {
-    const auto& autos = extension->GetBehaviorsTypes();
-    if (find(autos.begin(), autos.end(), autoType) != autos.end()) {
+    if (extension->HasBehavior(autoType)) {
       const auto& allAutoExpressions =
           extension->GetAllExpressionsForBehavior(autoType);
       if (allAutoExpressions.find(exprType) != allAutoExpressions.end())
@@ -292,8 +290,7 @@ MetadataProvider::GetExtensionAndBehaviorStrExpressionMetadata(
     const gd::Platform& platform, gd::String autoType, gd::String exprType) {
   auto& extensions = platform.GetAllPlatformExtensions();
   for (auto& extension : extensions) {
-    const auto& autos = extension->GetBehaviorsTypes();
-    if (find(autos.begin(), autos.end(), autoType) != autos.end()) {
+    if (extension->HasBehavior(autoType)) {
       const auto& allBehaviorStrExpressions =
           extension->GetAllStrExpressionsForBehavior(autoType);
       if (allBehaviorStrExpressions.find(exprType) !=
@@ -350,28 +347,30 @@ const gd::ExpressionMetadata& MetadataProvider::GetAnyExpressionMetadata(
     const gd::Platform& platform, gd::String exprType) {
   const auto& numberExpressionMetadata =
       GetExpressionMetadata(platform, exprType);
+  if (&numberExpressionMetadata != &badExpressionMetadata) {
+    return numberExpressionMetadata;
+  }
   const auto& stringExpressionMetadata =
       GetStrExpressionMetadata(platform, exprType);
-
-  return &numberExpressionMetadata != &badExpressionMetadata
-             ? numberExpressionMetadata
-             : &stringExpressionMetadata != &badExpressionMetadata
-                   ? stringExpressionMetadata
-                   : badExpressionMetadata;
+  if (&stringExpressionMetadata != &badExpressionMetadata) {
+    return stringExpressionMetadata;
+  }
+  return badExpressionMetadata;
 }
 
 const gd::ExpressionMetadata& MetadataProvider::GetObjectAnyExpressionMetadata(
     const gd::Platform& platform, gd::String objectType, gd::String exprType) {
   const auto& numberExpressionMetadata =
       GetObjectExpressionMetadata(platform, objectType, exprType);
+  if (&numberExpressionMetadata != &badExpressionMetadata) {
+    return numberExpressionMetadata;
+  }
   const auto& stringExpressionMetadata =
       GetObjectStrExpressionMetadata(platform, objectType, exprType);
-
-  return &numberExpressionMetadata != &badExpressionMetadata
-             ? numberExpressionMetadata
-             : &stringExpressionMetadata != &badExpressionMetadata
-                   ? stringExpressionMetadata
-                   : badExpressionMetadata;
+  if (&stringExpressionMetadata != &badExpressionMetadata) {
+    return stringExpressionMetadata;
+  }
+  return badExpressionMetadata;
 }
 
 const gd::ExpressionMetadata&
@@ -380,14 +379,98 @@ MetadataProvider::GetBehaviorAnyExpressionMetadata(const gd::Platform& platform,
                                                    gd::String exprType) {
   const auto& numberExpressionMetadata =
       GetBehaviorExpressionMetadata(platform, autoType, exprType);
+  if (&numberExpressionMetadata != &badExpressionMetadata) {
+    return numberExpressionMetadata;
+  }
   const auto& stringExpressionMetadata =
       GetBehaviorStrExpressionMetadata(platform, autoType, exprType);
+  if (&stringExpressionMetadata != &badExpressionMetadata) {
+    return stringExpressionMetadata;
+  }
+  return badExpressionMetadata;
+}
 
-  return &numberExpressionMetadata != &badExpressionMetadata
-             ? numberExpressionMetadata
-             : &stringExpressionMetadata != &badExpressionMetadata
-                   ? stringExpressionMetadata
-                   : badExpressionMetadata;
+const gd::ExpressionMetadata& MetadataProvider::GetFunctionCallMetadata(
+    const gd::Platform& platform, 
+    const gd::ObjectsContainer &globalObjectsContainer,
+    const gd::ObjectsContainer &objectsContainer,
+    FunctionCallNode& node) {
+
+  if (!node.behaviorName.empty()) {
+    gd::String behaviorType = 
+        GetTypeOfBehavior(globalObjectsContainer, objectsContainer, node.behaviorName);
+    return MetadataProvider::GetBehaviorAnyExpressionMetadata(
+            platform, behaviorType, node.functionName);
+  }
+  else if (!node.objectName.empty()) {
+    gd::String objectType = 
+        GetTypeOfObject(globalObjectsContainer, objectsContainer, node.objectName);
+    return MetadataProvider::GetObjectAnyExpressionMetadata(
+                  platform, objectType, node.functionName);
+  }
+
+  return MetadataProvider::GetAnyExpressionMetadata(platform, node.functionName);
+}
+
+  const gd::ParameterMetadata* MetadataProvider::GetFunctionCallParameterMetadata(
+    const gd::Platform& platform, 
+    const gd::ObjectsContainer &globalObjectsContainer,
+    const gd::ObjectsContainer &objectsContainer,
+    FunctionCallNode& functionCall,
+    ExpressionNode& parameter) {
+      int parameterIndex = -1;
+      for (int i = 0; i < functionCall.parameters.size(); i++) {
+        if (functionCall.parameters.at(i).get() == &parameter) {
+          parameterIndex = i;
+          break;
+        }
+      }
+      if (parameterIndex < 0) {
+        return nullptr;
+      }
+      return MetadataProvider::GetFunctionCallParameterMetadata(
+          platform, 
+          globalObjectsContainer,
+          objectsContainer,
+          functionCall,
+          parameterIndex);
+}
+
+  const gd::ParameterMetadata* MetadataProvider::GetFunctionCallParameterMetadata(
+    const gd::Platform& platform, 
+    const gd::ObjectsContainer &globalObjectsContainer,
+    const gd::ObjectsContainer &objectsContainer,
+    FunctionCallNode& functionCall,
+    int parameterIndex) {
+      // Search the parameter metadata index skipping invisible ones.
+      size_t visibleParameterIndex = 0;
+      size_t metadataParameterIndex =
+          ExpressionParser2::WrittenParametersFirstIndex(
+              functionCall.objectName, functionCall.behaviorName);
+      const gd::ExpressionMetadata &metadata = MetadataProvider::GetFunctionCallMetadata(
+          platform, globalObjectsContainer, objectsContainer, functionCall);
+
+      if (IsBadExpressionMetadata(metadata)) {
+        return nullptr;
+      }
+
+      // TODO use a badMetadata instead of a nullptr?
+      const gd::ParameterMetadata* parameterMetadata = nullptr;
+      while (metadataParameterIndex <
+             metadata.parameters.size()) {
+        if (!metadata.parameters[metadataParameterIndex]
+                 .IsCodeOnly()) {
+          if (visibleParameterIndex == parameterIndex) {
+            parameterMetadata = &metadata.parameters[metadataParameterIndex];
+          }
+          visibleParameterIndex++;
+        }
+        metadataParameterIndex++;
+      }
+      const int visibleParameterCount = visibleParameterIndex;
+      // It can be null if there are too many parameters in the expression, this text node is
+      // not actually linked to a parameter expected by the function call.
+      return parameterMetadata;
 }
 
 MetadataProvider::~MetadataProvider() {}

Core/GDCore/Extensions/Metadata/MetadataProvider.h

@@ -15,6 +15,8 @@ class ExpressionMetadata;
 class ExpressionMetadata;
 class Platform;
 class PlatformExtension;
+struct FunctionCallNode;
+struct ExpressionNode;
 }  // namespace gd
 
 namespace gd {
@@ -234,6 +236,26 @@ class GD_CORE_API MetadataProvider {
   static const gd::ExpressionMetadata& GetObjectAnyExpressionMetadata(
       const gd::Platform& platform, gd::String objectType, gd::String exprType);
 
+  static const gd::ExpressionMetadata& GetFunctionCallMetadata(
+    const gd::Platform& platform, 
+    const gd::ObjectsContainer &globalObjectsContainer,
+    const gd::ObjectsContainer &objectsContainer,
+    FunctionCallNode& node);
+
+  static const gd::ParameterMetadata* GetFunctionCallParameterMetadata(
+    const gd::Platform& platform, 
+    const gd::ObjectsContainer &globalObjectsContainer,
+    const gd::ObjectsContainer &objectsContainer,
+    FunctionCallNode& functionCall,
+    ExpressionNode& parameter);
+
+  static const gd::ParameterMetadata* GetFunctionCallParameterMetadata(
+    const gd::Platform& platform, 
+    const gd::ObjectsContainer &globalObjectsContainer,
+    const gd::ObjectsContainer &objectsContainer,
+    FunctionCallNode& functionCall,
+    int parameterIndex);
+
   /**
    * Get information about an expression from its type.
    * Works for behavior expressions.

Core/GDCore/Extensions/Metadata/ParameterMetadata.cpp

@@ -35,4 +35,18 @@ void ParameterMetadata::UnserializeFrom(const SerializerElement& element) {
   name = element.GetStringAttribute("name");
 }
 
+  // TODO factorize in a file with an enum and helpers?
+  const gd::String ParameterMetadata::numberType = "number";
+  const gd::String ParameterMetadata::stringType = "string";
+
+  const gd::String &ParameterMetadata::GetExpressionValueType(const gd::String &parameterType) {
+    if (parameterType == "number" || gd::ParameterMetadata::IsExpression("number", parameterType)) {
+      return ParameterMetadata::numberType;
+    }
+    if (parameterType == "string" || gd::ParameterMetadata::IsExpression("string", parameterType)) {
+      return ParameterMetadata::stringType;
+    }
+    return parameterType;
+  }
+
 }  // namespace gd

Core/GDCore/Extensions/Metadata/ParameterMetadata.h

@@ -207,6 +207,15 @@ class GD_CORE_API ParameterMetadata {
     return false;
   }
 
+  /**
+   * \brief Return the expression type from the parameter type.
+   * Declinations of "number" and "string" types (like "forceMultiplier" or
+   * "sceneName") are replaced by "number" and "string".
+   */
+  static const gd::String &GetExpressionValueType(const gd::String &parameterType);
+  static const gd::String numberType;
+  static const gd::String stringType;
+
   /** \name Serialization
    */
   ///@{

Core/GDCore/Extensions/Metadata/ParameterMetadataTools.cpp

@@ -14,7 +14,7 @@
 
 namespace gd {
 void ParameterMetadataTools::ParametersToObjectsContainer(
-    gd::Project& project,
+    const gd::Project& project,
     const std::vector<gd::ParameterMetadata>& parameters,
     gd::ObjectsContainer& outputObjectsContainer) {
   outputObjectsContainer.GetObjects().clear();
@@ -59,13 +59,13 @@ void ParameterMetadataTools::IterateOverParameters(
     const std::vector<gd::Expression>& parameters,
     const std::vector<gd::ParameterMetadata>& parametersMetadata,
     std::function<void(const gd::ParameterMetadata& parameterMetadata,
-                       const gd::String& parameterValue,
+                       const gd::Expression& parameterValue,
                        const gd::String& lastObjectName)> fn) {
   IterateOverParametersWithIndex(
       parameters,
       parametersMetadata,
       [&fn](const gd::ParameterMetadata& parameterMetadata,
-            const gd::String& parameterValue,
+            const gd::Expression& parameterValue,
             size_t parameterIndex,
             const gd::String& lastObjectName) {
         fn(parameterMetadata, parameterValue, lastObjectName);
@@ -76,17 +76,17 @@ void ParameterMetadataTools::IterateOverParametersWithIndex(
     const std::vector<gd::Expression>& parameters,
     const std::vector<gd::ParameterMetadata>& parametersMetadata,
     std::function<void(const gd::ParameterMetadata& parameterMetadata,
-                       const gd::String& parameterValue,
+                       const gd::Expression& parameterValue,
                        size_t parameterIndex,
                        const gd::String& lastObjectName)> fn) {
   gd::String lastObjectName = "";
   for (std::size_t pNb = 0; pNb < parametersMetadata.size(); ++pNb) {
     const gd::ParameterMetadata& parameterMetadata = parametersMetadata[pNb];
-    const gd::String& parameterValue =
+    const gd::Expression& parameterValue =
         pNb < parameters.size() ? parameters[pNb].GetPlainString() : "";
-    const gd::String& parameterValueOrDefault =
-        parameterValue.empty() && parameterMetadata.optional
-            ? parameterMetadata.GetDefaultValue()
+    const gd::Expression& parameterValueOrDefault =
+        parameterValue.GetPlainString().empty() && parameterMetadata.optional
+            ? Expression(parameterMetadata.GetDefaultValue())
             : parameterValue;
 
     fn(parameterMetadata, parameterValueOrDefault, pNb, lastObjectName);
@@ -97,7 +97,7 @@ void ParameterMetadataTools::IterateOverParametersWithIndex(
     // Search "lastObjectName" in the codebase for other place where this
     // convention is enforced.
     if (gd::ParameterMetadata::IsObject(parameterMetadata.GetType()))
-      lastObjectName = parameterValueOrDefault;
+      lastObjectName = parameterValueOrDefault.GetPlainString();
   }
 }
 

Core/GDCore/Extensions/Metadata/ParameterMetadataTools.h

@@ -19,7 +19,7 @@ namespace gd {
 class GD_CORE_API ParameterMetadataTools {
  public:
   static void ParametersToObjectsContainer(
-      gd::Project& project,
+      const gd::Project& project,
       const std::vector<gd::ParameterMetadata>& parameters,
       gd::ObjectsContainer& outputObjectsContainer);
 
@@ -32,7 +32,7 @@ class GD_CORE_API ParameterMetadataTools {
       const std::vector<gd::Expression>& parameters,
       const std::vector<gd::ParameterMetadata>& parametersMetadata,
       std::function<void(const gd::ParameterMetadata& parameterMetadata,
-                         const gd::String& parameterValue,
+                         const gd::Expression& parameterValue,
                          const gd::String& lastObjectName)> fn);
 
   /**
@@ -44,7 +44,7 @@ class GD_CORE_API ParameterMetadataTools {
       const std::vector<gd::Expression>& parameters,
       const std::vector<gd::ParameterMetadata>& parametersMetadata,
       std::function<void(const gd::ParameterMetadata& parameterMetadata,
-                         const gd::String& parameterValue,
+                         const gd::Expression& parameterValue,
                          size_t parameterIndex,
                          const gd::String& lastObjectName)> fn);
 

Core/GDCore/Extensions/PlatformExtension.cpp

@@ -346,6 +346,11 @@ gd::BehaviorMetadata& PlatformExtension::GetBehaviorMetadata(
   return badBehaviorMetadata;
 }
 
+bool PlatformExtension::HasBehavior(
+    const gd::String& behaviorType) const {
+  return behaviorsInfo.find(behaviorType) != behaviorsInfo.end();
+}
+
 gd::EffectMetadata& PlatformExtension::GetEffectMetadata(
     const gd::String& effectName) {
   if (effectsMetadata.find(effectName) != effectsMetadata.end())

Core/GDCore/Extensions/PlatformExtension.h

@@ -467,6 +467,12 @@ class GD_CORE_API PlatformExtension {
    */
   BehaviorMetadata& GetBehaviorMetadata(const gd::String& behaviorType);
 
+  /**
+   * \brief Return true if the extension contains a behavior associated to \a
+   * behaviorType
+   */
+  bool HasBehavior(const gd::String& behaviorType) const;
+
   /**
    * \brief Return the metadata for the effect with the given name.
    */

Core/GDCore/IDE/Events/EventsBehaviorRenamer.cpp

@@ -11,7 +11,6 @@
 
 #include "GDCore/Events/Event.h"
 #include "GDCore/Events/EventsList.h"
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
@@ -118,27 +117,20 @@ bool EventsBehaviorRenamer::DoVisitInstruction(gd::Instruction& instruction,
       instruction.GetParameters(),
       metadata.GetParameters(),
       [&](const gd::ParameterMetadata& parameterMetadata,
-          const gd::String& parameterValue,
+          const gd::Expression& parameterValue,
           size_t parameterIndex,
           const gd::String& lastObjectName) {
         const gd::String& type = parameterMetadata.type;
 
         if (gd::ParameterMetadata::IsBehavior(type)) {
           if (lastObjectName == objectName) {
-            if (parameterValue == oldBehaviorName) {
+            if (parameterValue.GetPlainString() == oldBehaviorName) {
               instruction.SetParameter(parameterIndex,
                                        gd::Expression(newBehaviorName));
             }
           }
         } else {
-          gd::ExpressionParser2 parser(
-              platform, GetGlobalObjectsContainer(), GetObjectsContainer());
-          auto node =
-              gd::ParameterMetadata::IsExpression("number", type)
-                  ? parser.ParseExpression("number", parameterValue)
-                  : (gd::ParameterMetadata::IsExpression("string", type)
-                         ? parser.ParseExpression("string", parameterValue)
-                         : std::unique_ptr<gd::ExpressionNode>());
+          auto node = parameterValue.GetRootNode();
           if (node) {
             ExpressionBehaviorRenamer renamer(GetGlobalObjectsContainer(),
                                               GetObjectsContainer(),

Core/GDCore/IDE/Events/EventsContextAnalyzer.cpp

@@ -9,7 +9,6 @@
 #include <vector>
 #include "GDCore/Events/Event.h"
 #include "GDCore/Events/EventsList.h"
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
@@ -17,6 +16,7 @@
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
 #include "GDCore/IDE/Events/ExpressionValidator.h"
+#include "GDCore/IDE/Events/ExpressionTypeFinder.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "GDCore/String.h"
@@ -31,7 +31,17 @@ namespace gd {
 class GD_CORE_API ExpressionObjectsAnalyzer
     : public ExpressionParser2NodeWorker {
  public:
-  ExpressionObjectsAnalyzer(EventsContext& context_) : context(context_){};
+  ExpressionObjectsAnalyzer(
+        const gd::Platform &platform_,
+        const gd::ObjectsContainer &globalObjectsContainer_,
+        const gd::ObjectsContainer &objectsContainer_,
+        const gd::String &rootType_,
+        EventsContext& context_) :
+        platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        rootType(rootType_),
+        context(context_){};
   virtual ~ExpressionObjectsAnalyzer(){};
 
  protected:
@@ -59,7 +69,8 @@ class GD_CORE_API ExpressionObjectsAnalyzer
     if (node.child) node.child->Visit(*this);
   }
   void OnVisitIdentifierNode(IdentifierNode& node) override {
-    if (gd::ParameterMetadata::IsObject(node.type)) {
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
+    if (gd::ParameterMetadata::IsObject(type)) {
       context.AddObjectName(node.identifierName);
     }
   }
@@ -87,6 +98,11 @@ class GD_CORE_API ExpressionObjectsAnalyzer
   void OnVisitEmptyNode(EmptyNode& node) override {}
 
  private:
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
+  const gd::String rootType;
+
   EventsContext& context;
 };
 
@@ -102,7 +118,7 @@ bool EventsContextAnalyzer::DoVisitInstruction(gd::Instruction& instruction,
       instruction.GetParameters(),
       instrInfo.parameters,
       [this](const gd::ParameterMetadata& parameterMetadata,
-             const gd::String& parameterValue,
+             const gd::Expression& parameterValue,
              const gd::String& lastObjectName) {
         AnalyzeParameter(platform,
                          project,
@@ -129,16 +145,14 @@ void EventsContextAnalyzer::AnalyzeParameter(
   if (ParameterMetadata::IsObject(type)) {
     context.AddObjectName(value);
   } else if (ParameterMetadata::IsExpression("number", type)) {
-    gd::ExpressionParser2 parser(platform, project, layout);
-    auto node = parser.ParseExpression("number", value);
+    auto node = parameter.GetRootNode();
 
-    ExpressionObjectsAnalyzer analyzer(context);
+    ExpressionObjectsAnalyzer analyzer(platform, project, layout, "number", context);
     node->Visit(analyzer);
   } else if (ParameterMetadata::IsExpression("string", type)) {
-    gd::ExpressionParser2 parser(platform, project, layout);
-    auto node = parser.ParseExpression("string", value);
+    auto node = parameter.GetRootNode();
 
-    ExpressionObjectsAnalyzer analyzer(context);
+    ExpressionObjectsAnalyzer analyzer(platform, project, layout, "string", context);
     node->Visit(analyzer);
   } else if (ParameterMetadata::IsBehavior(type)) {
     context.AddBehaviorName(lastObjectName, value);

Core/GDCore/IDE/Events/EventsRefactorer.cpp

@@ -11,7 +11,6 @@
 #include "GDCore/CommonTools.h"
 #include "GDCore/Events/Event.h"
 #include "GDCore/Events/EventsList.h"
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
@@ -20,6 +19,7 @@
 #include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/ObjectsContainer.h"
 #include "GDCore/IDE/Events/InstructionSentenceFormatter.h"
+#include "GDCore/IDE/Events/ExpressionTypeFinder.h"
 
 using namespace std;
 
@@ -34,18 +34,30 @@ const gd::String EventsRefactorer::searchIgnoredCharacters = ";:,#()";
  */
 class GD_CORE_API ExpressionObjectRenamer : public ExpressionParser2NodeWorker {
  public:
-  ExpressionObjectRenamer(const gd::String& objectName_,
+  ExpressionObjectRenamer(const gd::Platform &platform_,
+                          const gd::ObjectsContainer &globalObjectsContainer_,
+                          const gd::ObjectsContainer &objectsContainer_,
+                          const gd::String &rootType_,
+                          const gd::String& objectName_,
                           const gd::String& objectNewName_)
-      : hasDoneRenaming(false),
+      : platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        rootType(rootType_),
+        hasDoneRenaming(false),
         objectName(objectName_),
         objectNewName(objectNewName_){};
   virtual ~ExpressionObjectRenamer(){};
 
-  static bool Rename(gd::ExpressionNode& node,
+  static bool Rename(const gd::Platform &platform,
+                     const gd::ObjectsContainer &globalObjectsContainer,
+                     const gd::ObjectsContainer &objectsContainer,
+                     const gd::String &rootType,
+                     gd::ExpressionNode& node,
                      const gd::String& objectName,
                      const gd::String& objectNewName) {
-    if (ExpressionValidator::HasNoErrors(node)) {
-      ExpressionObjectRenamer renamer(objectName, objectNewName);
+    if (gd::ExpressionValidator::HasNoErrors(platform, globalObjectsContainer, objectsContainer, rootType, node)) {
+      ExpressionObjectRenamer renamer(platform, globalObjectsContainer, objectsContainer, rootType, objectName, objectNewName);
       node.Visit(renamer);
 
       return renamer.HasDoneRenaming();
@@ -81,7 +93,8 @@ class GD_CORE_API ExpressionObjectRenamer : public ExpressionParser2NodeWorker {
     if (node.child) node.child->Visit(*this);
   }
   void OnVisitIdentifierNode(IdentifierNode& node) override {
-    if (gd::ParameterMetadata::IsObject(node.type) &&
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
+    if (gd::ParameterMetadata::IsObject(type) &&
         node.identifierName == objectName) {
       hasDoneRenaming = true;
       node.identifierName = objectNewName;
@@ -108,6 +121,11 @@ class GD_CORE_API ExpressionObjectRenamer : public ExpressionParser2NodeWorker {
   bool hasDoneRenaming;
   const gd::String& objectName;
   const gd::String& objectNewName;
+  
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
+  const gd::String rootType;
 };
 
 /**
@@ -118,14 +136,27 @@ class GD_CORE_API ExpressionObjectRenamer : public ExpressionParser2NodeWorker {
  */
 class GD_CORE_API ExpressionObjectFinder : public ExpressionParser2NodeWorker {
  public:
-  ExpressionObjectFinder(const gd::String& objectName_)
-      : hasObject(false), objectName(objectName_){};
+  ExpressionObjectFinder(const gd::Platform &platform_,
+                         const gd::ObjectsContainer &globalObjectsContainer_,
+                         const gd::ObjectsContainer &objectsContainer_,
+                         const gd::String &rootType_,
+                         const gd::String& objectName_)
+      : platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        rootType(rootType_),
+        hasObject(false),
+        objectName(objectName_){};
   virtual ~ExpressionObjectFinder(){};
 
-  static bool CheckIfHasObject(gd::ExpressionNode& node,
+  static bool CheckIfHasObject(const gd::Platform &platform,
+                               const gd::ObjectsContainer &globalObjectsContainer,
+                               const gd::ObjectsContainer &objectsContainer,
+                               const gd::String &rootType,
+                               gd::ExpressionNode& node,
                                const gd::String& objectName) {
-    if (ExpressionValidator::HasNoErrors(node)) {
-      ExpressionObjectFinder finder(objectName);
+    if (gd::ExpressionValidator::HasNoErrors(platform, globalObjectsContainer, objectsContainer, rootType, node)) {
+      ExpressionObjectFinder finder(platform, globalObjectsContainer, objectsContainer, rootType, objectName);
       node.Visit(finder);
 
       return finder.HasFoundObject();
@@ -161,7 +192,8 @@ class GD_CORE_API ExpressionObjectFinder : public ExpressionParser2NodeWorker {
     if (node.child) node.child->Visit(*this);
   }
   void OnVisitIdentifierNode(IdentifierNode& node) override {
-    if (gd::ParameterMetadata::IsObject(node.type) &&
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
+    if (gd::ParameterMetadata::IsObject(type) &&
         node.identifierName == objectName) {
       hasObject = true;
     }
@@ -184,6 +216,11 @@ class GD_CORE_API ExpressionObjectFinder : public ExpressionParser2NodeWorker {
  private:
   bool hasObject;
   const gd::String& objectName;
+  
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
+  const gd::String rootType;
 };
 
 bool EventsRefactorer::RenameObjectInActions(const gd::Platform& platform,
@@ -205,11 +242,9 @@ bool EventsRefactorer::RenameObjectInActions(const gd::Platform& platform,
       // Replace object's name in expressions
       else if (ParameterMetadata::IsExpression(
                    "number", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "number", actions[aId].GetParameter(pNb).GetPlainString());
+        auto node = actions[aId].GetParameter(pNb).GetRootNode();
 
-        if (ExpressionObjectRenamer::Rename(*node, oldName, newName)) {
+        if (ExpressionObjectRenamer::Rename(platform, project, layout, "number", *node, oldName, newName)) {
           actions[aId].SetParameter(
               pNb, ExpressionParser2NodePrinter::PrintNode(*node));
         }
@@ -217,11 +252,9 @@ bool EventsRefactorer::RenameObjectInActions(const gd::Platform& platform,
       // Replace object's name in text expressions
       else if (ParameterMetadata::IsExpression(
                    "string", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "string", actions[aId].GetParameter(pNb).GetPlainString());
+        auto node = actions[aId].GetParameter(pNb).GetRootNode();
 
-        if (ExpressionObjectRenamer::Rename(*node, oldName, newName)) {
+        if (ExpressionObjectRenamer::Rename(platform, project, layout, "string", *node, oldName, newName)) {
           actions[aId].SetParameter(
               pNb, ExpressionParser2NodePrinter::PrintNode(*node));
         }
@@ -263,11 +296,9 @@ bool EventsRefactorer::RenameObjectInConditions(
       // Replace object's name in expressions
       else if (ParameterMetadata::IsExpression(
                    "number", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "number", conditions[cId].GetParameter(pNb).GetPlainString());
+        auto node = conditions[cId].GetParameter(pNb).GetRootNode();
 
-        if (ExpressionObjectRenamer::Rename(*node, oldName, newName)) {
+        if (ExpressionObjectRenamer::Rename(platform, project, layout, "number", *node, oldName, newName)) {
           conditions[cId].SetParameter(
               pNb, ExpressionParser2NodePrinter::PrintNode(*node));
         }
@@ -275,11 +306,9 @@ bool EventsRefactorer::RenameObjectInConditions(
       // Replace object's name in text expressions
       else if (ParameterMetadata::IsExpression(
                    "string", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "string", conditions[cId].GetParameter(pNb).GetPlainString());
+        auto node = conditions[cId].GetParameter(pNb).GetRootNode();
 
-        if (ExpressionObjectRenamer::Rename(*node, oldName, newName)) {
+        if (ExpressionObjectRenamer::Rename(platform, project, layout, "string", *node, oldName, newName)) {
           conditions[cId].SetParameter(
               pNb, ExpressionParser2NodePrinter::PrintNode(*node));
         }
@@ -316,20 +345,18 @@ bool EventsRefactorer::RenameObjectInEventParameters(
   // Replace object's name in expressions
   else if (ParameterMetadata::IsExpression("number",
                                            parameterMetadata.GetType())) {
-    gd::ExpressionParser2 parser(platform, project, layout);
-    auto node = parser.ParseExpression("number", expression.GetPlainString());
+    auto node = expression.GetRootNode();
 
-    if (ExpressionObjectRenamer::Rename(*node, oldName, newName)) {
+    if (ExpressionObjectRenamer::Rename(platform, project, layout, "number", *node, oldName, newName)) {
       expression = ExpressionParser2NodePrinter::PrintNode(*node);
     }
   }
   // Replace object's name in text expressions
   else if (ParameterMetadata::IsExpression("string",
                                            parameterMetadata.GetType())) {
-    gd::ExpressionParser2 parser(platform, project, layout);
-    auto node = parser.ParseExpression("string", expression.GetPlainString());
+    auto node = expression.GetRootNode();
 
-    if (ExpressionObjectRenamer::Rename(*node, oldName, newName)) {
+    if (ExpressionObjectRenamer::Rename(platform, project, layout, "string", *node, oldName, newName)) {
       expression = ExpressionParser2NodePrinter::PrintNode(*node);
     }
   }
@@ -405,11 +432,9 @@ bool EventsRefactorer::RemoveObjectInActions(const gd::Platform& platform,
       // Find object's name in expressions
       else if (ParameterMetadata::IsExpression(
                    "number", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "number", actions[aId].GetParameter(pNb).GetPlainString());
+        auto node = actions[aId].GetParameter(pNb).GetRootNode();
 
-        if (ExpressionObjectFinder::CheckIfHasObject(*node, name)) {
+        if (ExpressionObjectFinder::CheckIfHasObject(platform, project, layout, "number", *node, name)) {
           deleteMe = true;
           break;
         }
@@ -417,11 +442,9 @@ bool EventsRefactorer::RemoveObjectInActions(const gd::Platform& platform,
       // Find object's name in text expressions
       else if (ParameterMetadata::IsExpression(
                    "string", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "string", actions[aId].GetParameter(pNb).GetPlainString());
+        auto node = actions[aId].GetParameter(pNb).GetRootNode();
 
-        if (ExpressionObjectFinder::CheckIfHasObject(*node, name)) {
+        if (ExpressionObjectFinder::CheckIfHasObject(platform, project, layout, "string", *node, name)) {
           deleteMe = true;
           break;
         }
@@ -469,11 +492,9 @@ bool EventsRefactorer::RemoveObjectInConditions(
       // Find object's name in expressions
       else if (ParameterMetadata::IsExpression(
                    "number", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "number", conditions[cId].GetParameter(pNb).GetPlainString());
+        auto node = conditions[cId].GetParameter(pNb).GetRootNode();
 
-        if (ExpressionObjectFinder::CheckIfHasObject(*node, name)) {
+        if (ExpressionObjectFinder::CheckIfHasObject(platform, project, layout, "number", *node, name)) {
           deleteMe = true;
           break;
         }
@@ -481,11 +502,9 @@ bool EventsRefactorer::RemoveObjectInConditions(
       // Find object's name in text expressions
       else if (ParameterMetadata::IsExpression(
                    "string", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "string", conditions[cId].GetParameter(pNb).GetPlainString());
+        auto node = conditions[cId].GetParameter(pNb).GetRootNode();
 
-        if (ExpressionObjectFinder::CheckIfHasObject(*node, name)) {
+        if (ExpressionObjectFinder::CheckIfHasObject(platform, project, layout, "string", *node, name)) {
           deleteMe = true;
           break;
         }

Core/GDCore/IDE/Events/EventsVariablesFinder.cpp

@@ -7,7 +7,6 @@
 #include "EventsVariablesFinder.h"
 #include "GDCore/Events/Event.h"
 #include "GDCore/Events/Instruction.h"
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
@@ -32,10 +31,16 @@ namespace gd {
 class GD_CORE_API ExpressionParameterSearcher
     : public ExpressionParser2NodeWorker {
  public:
-  ExpressionParameterSearcher(std::set<gd::String>& results_,
+  ExpressionParameterSearcher(const gd::Platform &platform_,
+                              const gd::ObjectsContainer &globalObjectsContainer_,
+                              const gd::ObjectsContainer &objectsContainer_,
+                              std::set<gd::String>& results_,
                               const gd::String& parameterType_,
                               const gd::String& objectName_ = "")
-      : results(results_),
+      : platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        results(results_),
         parameterType(parameterType_),
         objectName(objectName_){};
   virtual ~ExpressionParameterSearcher(){};
@@ -68,10 +73,22 @@ class GD_CORE_API ExpressionParameterSearcher
   void OnVisitObjectFunctionNameNode(ObjectFunctionNameNode& node) override {}
   void OnVisitFunctionCallNode(FunctionCallNode& node) override {
     bool considerFunction = objectName.empty() || node.objectName == objectName;
+
+    const gd::ExpressionMetadata &metadata = node.objectName.empty() ?
+          MetadataProvider::GetAnyExpressionMetadata(platform, node.functionName) :
+            MetadataProvider::GetObjectAnyExpressionMetadata(
+                platform,
+                GetTypeOfObject(globalObjectsContainer, objectsContainer, objectName),
+                node.functionName);
+
+    if (gd::MetadataProvider::IsBadExpressionMetadata(metadata)) {
+      return;
+    }
+    
     for (size_t i = 0; i < node.parameters.size() &&
-                       i < node.expressionMetadata.parameters.size();
+                       i < metadata.parameters.size();
          ++i) {
-      auto& parameterMetadata = node.expressionMetadata.parameters[i];
+      auto& parameterMetadata = metadata.parameters[i];
       if (considerFunction && parameterMetadata.GetType() == parameterType) {
         // Store the value of the parameter
         results.insert(
@@ -84,6 +101,10 @@ class GD_CORE_API ExpressionParameterSearcher
   void OnVisitEmptyNode(EmptyNode& node) override {}
 
  private:
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
+
   std::set<gd::String>& results;  ///< Reference to the std::set where argument
                                   ///< values must be stored.
   gd::String parameterType;  ///< The type of the parameters to be searched for.
@@ -165,24 +186,18 @@ std::set<gd::String> EventsVariablesFinder::FindArgumentsInInstructions(
       }
       // Search in expressions
       else if (ParameterMetadata::IsExpression(
-                   "number", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "number", instructions[aId].GetParameter(pNb).GetPlainString());
-
-        ExpressionParameterSearcher searcher(
-            results, parameterType, objectName);
-        node->Visit(searcher);
-      }
-      // Search in gd::String expressions
-      else if (ParameterMetadata::IsExpression(
+                   "number", instrInfos.parameters[pNb].type) ||
+               ParameterMetadata::IsExpression(
                    "string", instrInfos.parameters[pNb].type)) {
-        gd::ExpressionParser2 parser(platform, project, layout);
-        auto node = parser.ParseExpression(
-            "number", instructions[aId].GetParameter(pNb).GetPlainString());
+        auto node = instructions[aId].GetParameter(pNb).GetRootNode();
 
         ExpressionParameterSearcher searcher(
-            results, parameterType, objectName);
+            platform,
+            project,
+            layout,
+            results,
+            parameterType,
+            objectName);
         node->Visit(searcher);
       }
       // Remember the value of the last "object" parameter.

Core/GDCore/IDE/Events/ExpressionCompletionFinder.h

@@ -15,6 +15,8 @@
 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
 #include "GDCore/Extensions/Metadata/InstructionMetadata.h"
 #include "GDCore/IDE/Events/ExpressionNodeLocationFinder.h"
+#include "GDCore/IDE/Events/ExpressionTypeFinder.h"
+#include "GDCore/IDE/Events/ExpressionVariableOwnerFinder.h"
 
 namespace gd {
 class Expression;
@@ -290,7 +292,11 @@ class GD_CORE_API ExpressionCompletionFinder
    * and returns completions for it.
    */
   static std::vector<ExpressionCompletionDescription>
-  GetCompletionDescriptionsFor(gd::ExpressionNode& node,
+  GetCompletionDescriptionsFor(const gd::Platform &platform,
+                               const gd::ObjectsContainer &globalObjectsContainer,
+                               const gd::ObjectsContainer &objectsContainer,
+                               const gd::String &rootType,
+                               gd::ExpressionNode& node,
                                size_t searchedPosition) {
     gd::ExpressionNodeLocationFinder finder(searchedPosition);
     node.Visit(finder);
@@ -303,6 +309,7 @@ class GD_CORE_API ExpressionCompletionFinder
 
     gd::ExpressionNode* maybeParentNodeAtLocation = finder.GetParentNode();
     gd::ExpressionCompletionFinder autocompletionProvider(
+        platform, globalObjectsContainer, objectsContainer, rootType,
         searchedPosition, maybeParentNodeAtLocation);
     nodeAtLocation->Visit(autocompletionProvider);
     return autocompletionProvider.GetCompletionDescriptions();
@@ -320,19 +327,21 @@ class GD_CORE_API ExpressionCompletionFinder
 
  protected:
   void OnVisitSubExpressionNode(SubExpressionNode& node) override {
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
     completions.push_back(ExpressionCompletionDescription::ForObject(
-        node.type, "", searchedPosition + 1, searchedPosition + 1));
+        type, "", searchedPosition + 1, searchedPosition + 1));
     completions.push_back(ExpressionCompletionDescription::ForExpression(
-        node.type, "", searchedPosition + 1, searchedPosition + 1));
+        type, "", searchedPosition + 1, searchedPosition + 1));
   }
   void OnVisitOperatorNode(OperatorNode& node) override {
     // No completions.
   }
   void OnVisitUnaryOperatorNode(UnaryOperatorNode& node) override {
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
     completions.push_back(ExpressionCompletionDescription::ForObject(
-        node.type, "", searchedPosition + 1, searchedPosition + 1));
+        type, "", searchedPosition + 1, searchedPosition + 1));
     completions.push_back(ExpressionCompletionDescription::ForExpression(
-        node.type, "", searchedPosition + 1, searchedPosition + 1));
+        type, "", searchedPosition + 1, searchedPosition + 1));
   }
   void OnVisitNumberNode(NumberNode& node) override {
     // No completions
@@ -344,6 +353,7 @@ class GD_CORE_API ExpressionCompletionFinder
     FunctionCallNode* functionCall =
         dynamic_cast<FunctionCallNode*>(maybeParentNodeAtLocation);
     if (functionCall != nullptr) {
+
       int parameterIndex = -1;
       for (int i = 0; i < functionCall->parameters.size(); i++) {
         if (functionCall->parameters.at(i).get() == &node) {
@@ -359,15 +369,16 @@ class GD_CORE_API ExpressionCompletionFinder
       size_t metadataParameterIndex =
           ExpressionParser2::WrittenParametersFirstIndex(
               functionCall->objectName, functionCall->behaviorName);
+      const gd::ExpressionMetadata &metadata = MetadataProvider::GetFunctionCallMetadata(
+          platform, globalObjectsContainer, objectsContainer, *functionCall);
 
       const gd::ParameterMetadata* parameterMetadata = nullptr;
       while (metadataParameterIndex <
-             functionCall->expressionMetadata.parameters.size()) {
-        if (!functionCall->expressionMetadata.parameters[metadataParameterIndex]
+             metadata.parameters.size()) {
+        if (!metadata.parameters[metadataParameterIndex]
                  .IsCodeOnly()) {
           if (visibleParameterIndex == parameterIndex) {
-            parameterMetadata = &functionCall->expressionMetadata
-                                     .parameters[metadataParameterIndex];
+            parameterMetadata = &metadata.parameters[metadataParameterIndex];
           }
           visibleParameterIndex++;
         }
@@ -398,12 +409,21 @@ class GD_CORE_API ExpressionCompletionFinder
     }
   }
   void OnVisitVariableNode(VariableNode& node) override {
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
+    auto objectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
+        platform,
+        globalObjectsContainer,
+        objectsContainer,
+        // Variable fields doesn't use expression completion,
+        // so the object will be found inside the expression itself.
+        "",
+        node);
     completions.push_back(ExpressionCompletionDescription::ForVariable(
-        node.type,
+        type,
         node.name,
         node.location.GetStartPosition(),
         node.location.GetEndPosition(),
-        node.objectName));
+        objectName));
   }
   void OnVisitVariableAccessorNode(VariableAccessorNode& node) override {
     // No completions
@@ -413,35 +433,69 @@ class GD_CORE_API ExpressionCompletionFinder
     // No completions
   }
   void OnVisitIdentifierNode(IdentifierNode& node) override {
-    if (gd::ParameterMetadata::IsObject(node.type)) {
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
+    if (gd::ParameterMetadata::IsObject(type)) {
       // Only show completions of objects if an object is required
       completions.push_back(ExpressionCompletionDescription::ForObject(
-          node.type,
+          type,
           node.identifierName,
           node.location.GetStartPosition(),
           node.location.GetEndPosition()));
+    } else if (gd::ParameterMetadata::IsExpression("variable", type)) {
+      auto objectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
+          platform,
+          globalObjectsContainer,
+          objectsContainer,
+          // Variable fields doesn't use expression completion,
+          // so the object will be found inside the expression itself.
+          "",
+          node);
+      completions.push_back(ExpressionCompletionDescription::ForVariable(
+          type,
+          node.identifierName,
+          node.location.GetStartPosition(),
+          node.location.GetEndPosition(),
+          objectName));
     } else {
-      // Show completions for expressions and objects otherwise.
-      completions.push_back(ExpressionCompletionDescription::ForObject(
-          node.type,
-          node.identifierName,
-          node.location.GetStartPosition(),
-          node.location.GetEndPosition()));
-      completions.push_back(ExpressionCompletionDescription::ForExpression(
-          node.type,
-          node.identifierName,
-          node.location.GetStartPosition(),
-          node.location.GetEndPosition()));
+      // Object function or behavior name
+      if (IsCaretOn(node.identifierNameLocation)) {
+        completions.push_back(ExpressionCompletionDescription::ForObject(
+            type,
+            node.identifierName,
+            node.identifierNameLocation.GetStartPosition(),
+            node.identifierNameLocation.GetEndPosition()));
+        if (!node.identifierNameDotLocation.IsValid()) {
+          completions.push_back(ExpressionCompletionDescription::ForExpression(
+              type,
+              node.identifierName,
+              node.identifierNameLocation.GetStartPosition(),
+              node.identifierNameLocation.GetEndPosition()));
+        }
+      } else if (IsCaretOn(node.identifierNameDotLocation) ||
+                 IsCaretOn(node.childIdentifierNameLocation)) {
+        completions.push_back(ExpressionCompletionDescription::ForBehavior(
+            node.childIdentifierName,
+            node.childIdentifierNameLocation.GetStartPosition(),
+            node.childIdentifierNameLocation.GetEndPosition(),
+            node.identifierName));
+        completions.push_back(ExpressionCompletionDescription::ForExpression(
+            type,
+            node.childIdentifierName,
+            node.childIdentifierNameLocation.GetStartPosition(),
+            node.childIdentifierNameLocation.GetEndPosition(),
+            node.identifierName));
+      }
     }
   }
   void OnVisitObjectFunctionNameNode(ObjectFunctionNameNode& node) override {
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
     if (!node.behaviorFunctionName.empty() ||
         node.behaviorNameNamespaceSeparatorLocation.IsValid()) {
       // Behavior function (or behavior function being written, with the
       // function name missing)
       if (IsCaretOn(node.objectNameLocation)) {
         completions.push_back(ExpressionCompletionDescription::ForObject(
-            node.type,
+            type,
             node.objectName,
             node.objectNameLocation.GetStartPosition(),
             node.objectNameLocation.GetEndPosition()));
@@ -455,7 +509,7 @@ class GD_CORE_API ExpressionCompletionFinder
       } else if (IsCaretOn(node.behaviorNameNamespaceSeparatorLocation) ||
                  IsCaretOn(node.behaviorFunctionNameLocation)) {
         completions.push_back(ExpressionCompletionDescription::ForExpression(
-            node.type,
+            type,
             node.behaviorFunctionName,
             node.behaviorFunctionNameLocation.GetStartPosition(),
             node.behaviorFunctionNameLocation.GetEndPosition(),
@@ -466,7 +520,7 @@ class GD_CORE_API ExpressionCompletionFinder
       // Object function or behavior name
       if (IsCaretOn(node.objectNameLocation)) {
         completions.push_back(ExpressionCompletionDescription::ForObject(
-            node.type,
+            type,
             node.objectName,
             node.objectNameLocation.GetStartPosition(),
             node.objectNameLocation.GetEndPosition()));
@@ -478,7 +532,7 @@ class GD_CORE_API ExpressionCompletionFinder
             node.objectFunctionOrBehaviorNameLocation.GetEndPosition(),
             node.objectName));
         completions.push_back(ExpressionCompletionDescription::ForExpression(
-            node.type,
+            type,
             node.objectFunctionOrBehaviorName,
             node.objectFunctionOrBehaviorNameLocation.GetStartPosition(),
             node.objectFunctionOrBehaviorNameLocation.GetEndPosition(),
@@ -487,6 +541,7 @@ class GD_CORE_API ExpressionCompletionFinder
     }
   }
   void OnVisitFunctionCallNode(FunctionCallNode& node) override {
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
     bool isCaretOnParenthesis = IsCaretOn(node.openingParenthesisLocation) ||
                                 IsCaretOn(node.closingParenthesisLocation);
 
@@ -494,7 +549,7 @@ class GD_CORE_API ExpressionCompletionFinder
       // Behavior function
       if (IsCaretOn(node.objectNameLocation)) {
         completions.push_back(ExpressionCompletionDescription::ForObject(
-            node.type,
+            type,
             node.objectName,
             node.objectNameLocation.GetStartPosition(),
             node.objectNameLocation.GetEndPosition()));
@@ -507,7 +562,7 @@ class GD_CORE_API ExpressionCompletionFinder
             node.objectName));
       } else {
         completions.push_back(ExpressionCompletionDescription::ForExpression(
-                                  node.type,
+                                  type,
                                   node.functionName,
                                   node.functionNameLocation.GetStartPosition(),
                                   node.functionNameLocation.GetEndPosition(),
@@ -519,7 +574,7 @@ class GD_CORE_API ExpressionCompletionFinder
       // Object function
       if (IsCaretOn(node.objectNameLocation)) {
         completions.push_back(ExpressionCompletionDescription::ForObject(
-            node.type,
+            type,
             node.objectName,
             node.objectNameLocation.GetStartPosition(),
             node.objectNameLocation.GetEndPosition()));
@@ -538,7 +593,7 @@ class GD_CORE_API ExpressionCompletionFinder
         }
 
         completions.push_back(ExpressionCompletionDescription::ForExpression(
-                                  node.type,
+                                  type,
                                   node.functionName,
                                   node.functionNameLocation.GetStartPosition(),
                                   node.functionNameLocation.GetEndPosition(),
@@ -548,7 +603,7 @@ class GD_CORE_API ExpressionCompletionFinder
     } else {
       // Free function
       completions.push_back(ExpressionCompletionDescription::ForExpression(
-                                node.type,
+                                type,
                                 node.functionName,
                                 node.functionNameLocation.GetStartPosition(),
                                 node.functionNameLocation.GetEndPosition())
@@ -556,13 +611,14 @@ class GD_CORE_API ExpressionCompletionFinder
     }
   }
   void OnVisitEmptyNode(EmptyNode& node) override {
+    auto type = gd::ExpressionTypeFinder::GetType(platform, globalObjectsContainer, objectsContainer, rootType, node);
     completions.push_back(ExpressionCompletionDescription::ForObject(
-        node.type,
+        type,
         node.text,
         node.location.GetStartPosition(),
         node.location.GetEndPosition()));
     completions.push_back(ExpressionCompletionDescription::ForExpression(
-        node.type,
+        type,
         node.text,
         node.location.GetStartPosition(),
         node.location.GetEndPosition()));
@@ -578,14 +634,27 @@ class GD_CORE_API ExpressionCompletionFinder
              (inclusive && searchedPosition <= location.GetEndPosition())));
   }
 
-  ExpressionCompletionFinder(size_t searchedPosition_,
+  ExpressionCompletionFinder(const gd::Platform &platform_,
+                             const gd::ObjectsContainer &globalObjectsContainer_,
+                             const gd::ObjectsContainer &objectsContainer_,
+                             const gd::String &rootType_,
+                             size_t searchedPosition_,
                              gd::ExpressionNode* maybeParentNodeAtLocation_)
-      : searchedPosition(searchedPosition_),
+      : platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        rootType(rootType_),
+        searchedPosition(searchedPosition_),
         maybeParentNodeAtLocation(maybeParentNodeAtLocation_){};
 
   std::vector<ExpressionCompletionDescription> completions;
   size_t searchedPosition;
   gd::ExpressionNode* maybeParentNodeAtLocation;
+  
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
+  const gd::String rootType;
 };
 
 }  // namespace gd

Core/GDCore/IDE/Events/ExpressionLeftSideTypeFinder.h

@@ -0,0 +1,123 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#ifndef GDCORE_EXPRESSIONLEFTSIDETYPEFINDER_H
+#define GDCORE_EXPRESSIONLEFTSIDETYPEFINDER_H
+
+#include <memory>
+#include <vector>
+#include "GDCore/Events/Parsers/ExpressionParser2Node.h"
+#include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
+#include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Extensions/Metadata/ObjectMetadata.h"
+#include "GDCore/Extensions/Metadata/ParameterMetadata.h"
+#include "GDCore/Project/Layout.h"  // For GetTypeOfObject and GetTypeOfBehavior
+#include "GDCore/Tools/Localization.h"
+
+namespace gd {
+class Expression;
+class ObjectsContainer;
+class Platform;
+class ParameterMetadata;
+class ExpressionMetadata;
+}  // namespace gd
+
+namespace gd {
+
+/**
+ * \brief Find the type of the node at the left side of operations.
+ *
+ * \see gd::ExpressionTypeFinder
+ */
+class GD_CORE_API ExpressionLeftSideTypeFinder : public ExpressionParser2NodeWorker {
+ public:
+
+  /**
+   * \brief Helper function to find the type of the node at the left side of
+   * operations.
+   */
+  static const gd::String GetType(const gd::Platform &platform,
+                      const gd::ObjectsContainer &globalObjectsContainer,
+                      const gd::ObjectsContainer &objectsContainer,
+                      gd::ExpressionNode& node) {
+    gd::ExpressionLeftSideTypeFinder typeFinder(
+        platform, globalObjectsContainer, objectsContainer);
+    node.Visit(typeFinder);
+    return typeFinder.GetType();
+  }
+
+  virtual ~ExpressionLeftSideTypeFinder(){};
+
+ protected:
+  ExpressionLeftSideTypeFinder(const gd::Platform &platform_,
+                       const gd::ObjectsContainer &globalObjectsContainer_,
+                       const gd::ObjectsContainer &objectsContainer_)
+      : platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        type("unknown") {};
+
+  const gd::String &GetType() {
+    return type;
+  };
+
+  void OnVisitSubExpressionNode(SubExpressionNode& node) override {
+    node.expression->Visit(*this);
+  }
+  void OnVisitOperatorNode(OperatorNode& node) override {
+    node.leftHandSide->Visit(*this);
+  }
+  void OnVisitUnaryOperatorNode(UnaryOperatorNode& node) override {
+    node.factor->Visit(*this);
+  }
+  void OnVisitVariableBracketAccessorNode(
+      VariableBracketAccessorNode& node) override {
+    node.expression->Visit(*this);
+  }
+  void OnVisitNumberNode(NumberNode& node) override {
+    type = "number";
+  }
+  void OnVisitTextNode(TextNode& node) override {
+    type = "string";
+  }
+  void OnVisitFunctionCallNode(FunctionCallNode& node) override {
+    const gd::ExpressionMetadata &metadata = MetadataProvider::GetFunctionCallMetadata(
+        platform, globalObjectsContainer, objectsContainer, node);
+    if (gd::MetadataProvider::IsBadExpressionMetadata(metadata)) {
+      type = "unknown";
+    }
+    else {
+      type = metadata.GetReturnType();
+    }
+  }
+  void OnVisitVariableNode(VariableNode& node) override {
+    type = "unknown";
+  }
+  void OnVisitVariableAccessorNode(VariableAccessorNode& node) override {
+    type = "unknown";
+  }
+  void OnVisitIdentifierNode(IdentifierNode& node) override {
+    type = "unknown";
+  }
+  void OnVisitEmptyNode(EmptyNode& node) override {
+    type = "unknown";
+  }
+  void OnVisitObjectFunctionNameNode(ObjectFunctionNameNode& node) override {
+    type = "unknown";
+  }
+
+ private:
+  gd::String type;
+
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
+  const gd::String rootType;
+};
+
+}  // namespace gd
+
+#endif  // GDCORE_EXPRESSIONLEFTSIDETYPEFINDER_H

Core/GDCore/IDE/Events/ExpressionTypeFinder.cpp

@@ -0,0 +1,35 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#include "GDCore/IDE/Events/ExpressionTypeFinder.h"
+
+#include <algorithm>
+#include <memory>
+#include <vector>
+
+#include "GDCore/CommonTools.h"
+#include "GDCore/Events/Expression.h"
+#include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
+#include "GDCore/Extensions/Metadata/InstructionMetadata.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Extensions/Metadata/ObjectMetadata.h"
+#include "GDCore/Extensions/Platform.h"
+#include "GDCore/Project/Layout.h"
+#include "GDCore/Project/Project.h"
+#include "GDCore/Tools/Localization.h"
+#include "GDCore/Tools/MakeUnique.h"
+#include "GDCore/Events/Parsers/ExpressionParser2.h"
+
+using namespace std;
+
+namespace gd {
+
+  // TODO factorize in a file with an enum and helpers?
+  const gd::String ExpressionTypeFinder::unknownType = "unknown";
+  const gd::String ExpressionTypeFinder::numberType = "number";
+  const gd::String ExpressionTypeFinder::stringType = "string";
+  const gd::String ExpressionTypeFinder::numberOrStringType = "number|string";
+
+}  // namespace gd

Core/GDCore/IDE/Events/ExpressionTypeFinder.h

@@ -0,0 +1,198 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#ifndef GDCORE_EXPRESSIONTYPEFINDER_H
+#define GDCORE_EXPRESSIONTYPEFINDER_H
+
+#include <memory>
+#include <vector>
+#include "GDCore/Events/Parsers/ExpressionParser2Node.h"
+#include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
+#include "GDCore/IDE/Events/ExpressionLeftSideTypeFinder.h"
+#include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Extensions/Metadata/ObjectMetadata.h"
+#include "GDCore/Extensions/Metadata/ParameterMetadata.h"
+#include "GDCore/Project/Layout.h" // For GetTypeOfObject and GetTypeOfBehavior
+#include "GDCore/Tools/Localization.h"
+
+namespace gd {
+class Expression;
+class ObjectsContainer;
+class Platform;
+class ParameterMetadata;
+class ExpressionMetadata;
+}  // namespace gd
+
+namespace gd {
+
+/**
+ * \brief Find the type of the expression or sub-expression that a given node
+ * represents.
+ * 
+ * The type returned by this worker is a mix of:
+ * - an expected type looking up like a parameter declaration
+ * - an actual type looking down, but only looking at the most left branch
+ *   (using ExpressionLeftSideTypeFinder)
+ *
+ * This logic was built with the constraint of following a parser that can't
+ * know the right side. Now that it is extracted, it could be enhanced if needed.
+ *
+ * \see gd::ExpressionParser2
+ */
+class GD_CORE_API ExpressionTypeFinder : public ExpressionParser2NodeWorker {
+ public:
+
+  /**
+   * \brief Helper function to find the type of the expression or
+   * sub-expression that a given node represents.
+   */
+  static const gd::String GetType(const gd::Platform &platform,
+                      const gd::ObjectsContainer &globalObjectsContainer,
+                      const gd::ObjectsContainer &objectsContainer,
+                      const gd::String &rootType,
+                      gd::ExpressionNode& node) {
+    gd::ExpressionTypeFinder typeFinder(
+        platform, globalObjectsContainer, objectsContainer, rootType);
+    node.Visit(typeFinder);
+    return typeFinder.GetType();
+  }
+
+  virtual ~ExpressionTypeFinder(){};
+
+ protected:
+  ExpressionTypeFinder(const gd::Platform &platform_,
+                       const gd::ObjectsContainer &globalObjectsContainer_,
+                       const gd::ObjectsContainer &objectsContainer_,
+                       const gd::String &rootType_)
+      : platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        rootType(rootType_),
+        type(ExpressionTypeFinder::unknownType),
+        child(nullptr) {};
+
+  const gd::String &GetType() {
+    return gd::ParameterMetadata::GetExpressionValueType(type);
+  };
+
+  void OnVisitSubExpressionNode(SubExpressionNode& node) override {
+    VisitParent(node);
+  }
+  void OnVisitOperatorNode(OperatorNode& node) override {
+    VisitParent(node);
+  }
+  void OnVisitUnaryOperatorNode(UnaryOperatorNode& node) override {
+    VisitParent(node);
+  }
+  void OnVisitNumberNode(NumberNode& node) override {
+    type = ExpressionTypeFinder::numberType;
+  }
+  void OnVisitTextNode(TextNode& node) override {
+    type = ExpressionTypeFinder::stringType;
+  }
+  void OnVisitVariableNode(VariableNode& node) override {
+    VisitParent(node);
+  }
+  void OnVisitVariableAccessorNode(VariableAccessorNode& node) override {
+    VisitParent(node);
+  }
+  void OnVisitIdentifierNode(IdentifierNode& node) override {
+    VisitParent(node);
+  }
+  void OnVisitEmptyNode(EmptyNode& node) override {
+    VisitParent(node);
+  }
+  void OnVisitObjectFunctionNameNode(ObjectFunctionNameNode& node) override {
+    VisitParent(node);
+  }
+  void OnVisitVariableBracketAccessorNode(
+      VariableBracketAccessorNode& node) override {
+    if (child == nullptr) {
+      type = ExpressionTypeFinder::unknownType;
+    }
+    auto leftSideType = gd::ExpressionLeftSideTypeFinder::GetType(
+        platform, 
+        globalObjectsContainer,
+        objectsContainer,
+        node);
+    if (leftSideType == ExpressionTypeFinder::numberType
+     || leftSideType == ExpressionTypeFinder::stringType) {
+      type = leftSideType;
+    }
+    else {
+      type = ExpressionTypeFinder::numberOrStringType;
+    }
+  }
+  void OnVisitFunctionCallNode(FunctionCallNode& node) override {
+    if (child == nullptr) {
+      const gd::ExpressionMetadata &metadata = MetadataProvider::GetFunctionCallMetadata(
+          platform, globalObjectsContainer, objectsContainer, node);
+      if (gd::MetadataProvider::IsBadExpressionMetadata(metadata)) {
+        VisitParent(node);
+      }
+      else {
+        type = metadata.GetReturnType();
+      }
+    }
+    else {
+      const gd::ParameterMetadata* parameterMetadata =
+          gd::MetadataProvider::GetFunctionCallParameterMetadata(
+              platform,
+              globalObjectsContainer,
+              objectsContainer,
+              node,
+              *child);
+      if (parameterMetadata == nullptr || parameterMetadata->GetType().empty()) {
+        type = ExpressionTypeFinder::unknownType;
+      }
+      else {
+        type = parameterMetadata->GetType();
+      }
+    }
+  }
+
+ private:
+  inline void VisitParent(ExpressionNode& node) {
+    child = &node;
+    if (node.parent != nullptr) {
+      node.parent->Visit(*this);
+    }
+    else if (rootType == ExpressionTypeFinder::numberOrStringType) {
+      auto leftSideType = gd::ExpressionLeftSideTypeFinder::GetType(
+          platform, 
+          globalObjectsContainer,
+          objectsContainer,
+          node);
+      if (leftSideType == ExpressionTypeFinder::numberType
+       || leftSideType == ExpressionTypeFinder::stringType) {
+        type = leftSideType;
+      }
+      else {
+        type = rootType;
+      }
+    }
+    else {
+      type = rootType;
+    }
+  }
+
+  static const gd::String unknownType;
+  static const gd::String numberType;
+  static const gd::String stringType;
+  static const gd::String numberOrStringType;
+
+  gd::String type;
+  ExpressionNode *child;
+
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
+  const gd::String rootType;
+};
+
+}  // namespace gd
+
+#endif  // GDCORE_EXPRESSIONTYPEFINDER_H

Core/GDCore/IDE/Events/ExpressionValidator.cpp

@@ -0,0 +1,300 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#include "GDCore/IDE/Events/ExpressionValidator.h"
+
+#include <algorithm>
+#include <memory>
+#include <vector>
+
+#include "GDCore/CommonTools.h"
+#include "GDCore/Events/Expression.h"
+#include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
+#include "GDCore/Extensions/Metadata/InstructionMetadata.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Extensions/Metadata/ObjectMetadata.h"
+#include "GDCore/Extensions/Platform.h"
+#include "GDCore/Project/Layout.h"
+#include "GDCore/Project/Project.h"
+#include "GDCore/Tools/Localization.h"
+#include "GDCore/Tools/MakeUnique.h"
+#include "GDCore/Events/Parsers/ExpressionParser2.h"
+
+using namespace std;
+
+namespace gd {
+
+namespace {
+/**
+ * Return the minimum number of parameters, starting from a given parameter
+ * (by convention, 1 for object functions and 2 for behavior functions).
+ */
+size_t GetMinimumParametersNumber(
+    const std::vector<gd::ParameterMetadata>& parameters,
+    size_t initialParameterIndex) {
+  size_t nb = 0;
+  for (std::size_t i = initialParameterIndex; i < parameters.size(); ++i) {
+    if (!parameters[i].optional && !parameters[i].codeOnly) nb++;
+  }
+
+  return nb;
+}
+
+/**
+ * Return the maximum number of parameters, starting from a given parameter
+ * (by convention, 1 for object functions and 2 for behavior functions).
+ */
+size_t GetMaximumParametersNumber(
+    const std::vector<gd::ParameterMetadata>& parameters,
+    size_t initialParameterIndex) {
+  size_t nb = 0;
+  for (std::size_t i = initialParameterIndex; i < parameters.size(); ++i) {
+    if (!parameters[i].codeOnly) nb++;
+  }
+
+  return nb;
+}
+
+}  // namespace
+
+ExpressionValidator::Type ExpressionValidator::ValidateFunction(const gd::FunctionCallNode& function) {
+
+  ReportAnyError(function);
+  
+  gd::String objectType = function.objectName.empty() ? "" :
+      GetTypeOfObject(globalObjectsContainer, objectsContainer, function.objectName);
+      
+  gd::String behaviorType = function.behaviorName.empty() ? "" :
+      GetTypeOfBehavior(globalObjectsContainer, objectsContainer, function.behaviorName);
+
+  const gd::ExpressionMetadata &metadata = function.behaviorName.empty() ?
+      function.objectName.empty() ?
+          MetadataProvider::GetAnyExpressionMetadata(platform, function.functionName) :
+          MetadataProvider::GetObjectAnyExpressionMetadata(
+              platform, objectType, function.functionName) : 
+      MetadataProvider::GetBehaviorAnyExpressionMetadata(
+            platform, behaviorType, function.functionName);
+
+  if (!function.objectName.empty()) {
+    // If the function needs a capability on the object that may not be covered
+    // by all objects, check it now.
+    if (!metadata.GetRequiredBaseObjectCapability().empty()) {
+      const gd::ObjectMetadata &objectMetadata =
+          MetadataProvider::GetObjectMetadata(platform, objectType);
+
+      if (objectMetadata.IsUnsupportedBaseObjectCapability(
+              metadata.GetRequiredBaseObjectCapability())) {
+        RaiseTypeError(
+            _("This expression exists, but it can't be used on this object."),
+            function.objectNameLocation);
+        return StringToType(metadata.GetReturnType());
+      }
+    }
+  }
+
+  Type returnType = StringToType(metadata.GetReturnType());
+
+  if (gd::MetadataProvider::IsBadExpressionMetadata(metadata)) {
+    RaiseError(
+        "invalid_function_name",
+        _("Cannot find an expression with this name: ") +
+            function.functionName + "\n" +
+            _("Double check that you've not made any typo in the name."),
+        function.location);
+      return returnType;
+  }
+
+  // Validate the type of the function
+  if (returnType == Type::Number) {
+    if (parentType == Type::String) {
+      RaiseTypeError(
+          _("You tried to use an expression that returns a number, but a "
+            "string is expected. Use `ToString` if you need to convert a "
+            "number to a string."),
+          function.location);
+      return returnType;
+    }
+    else if (parentType != Type::Number && parentType != Type::NumberOrString) {
+      RaiseTypeError(_("You tried to use an expression that returns a "
+                              "number, but another type is expected:") +
+                              " " + TypeToString(parentType),
+                            function.location);
+      return returnType;
+    }
+  } else if (returnType == Type::String) {
+    if (parentType == Type::Number) {
+      RaiseTypeError(
+          _("You tried to use an expression that returns a string, but a "
+            "number is expected. Use `ToNumber` if you need to convert a "
+            "string to a number."),
+          function.location);
+      return returnType;
+    }
+    else if (parentType != Type::String && parentType != Type::NumberOrString) {
+      RaiseTypeError(_("You tried to use an expression that returns a "
+                              "string, but another type is expected:") +
+                              " " + TypeToString(parentType),
+                            function.location);
+      return returnType;
+    }
+  } else {
+    if (parentType != returnType) {
+      RaiseTypeError(
+          _("You tried to use an expression with the wrong return type:") + " " +
+            TypeToString(returnType),
+          function.location);
+      return returnType;
+    }
+  }
+
+  // Validate parameters count
+  size_t minParametersCount = GetMinimumParametersNumber(
+      metadata.parameters,
+      ExpressionParser2::WrittenParametersFirstIndex(function.objectName, function.behaviorName));
+  size_t maxParametersCount = GetMaximumParametersNumber(
+      metadata.parameters,
+      ExpressionParser2::WrittenParametersFirstIndex(function.objectName, function.behaviorName));
+  if (function.parameters.size() < minParametersCount ||
+      function.parameters.size() > maxParametersCount) {
+    gd::String expectedCountMessage =
+        minParametersCount == maxParametersCount
+            ? _("The number of parameters must be exactly ") +
+                  gd::String::From(minParametersCount)
+            : _("The number of parameters must be: ") +
+                  gd::String::From(minParametersCount) + "-" +
+                  gd::String::From(maxParametersCount);
+
+    if (function.parameters.size() < minParametersCount) {
+      RaiseError(
+          "too_few_parameters",
+          _("You have not entered enough parameters for the expression.") + " " +
+              expectedCountMessage,
+          function.location);
+    }
+    else {
+      RaiseError(
+          "extra_parameter",
+          _("This parameter was not expected by this expression. Remove it "
+          "or verify that you've entered the proper expression name.") + " " +
+              expectedCountMessage,
+          ExpressionParserLocation(
+              function.parameters[maxParametersCount]->location.GetStartPosition(),
+              function.location.GetEndPosition() - 1));
+    }
+    return returnType;
+  }
+
+  // TODO: reverse the order of diagnostic?
+  size_t writtenParametersFirstIndex =
+      ExpressionParser2::WrittenParametersFirstIndex(
+          function.objectName, function.behaviorName);
+  int metadataIndex = writtenParametersFirstIndex;
+  for (int parameterIndex = 0; parameterIndex < function.parameters.size(); parameterIndex++) {
+    auto& parameter = function.parameters[parameterIndex];
+    while (metadata.GetParameters()[metadataIndex].IsCodeOnly()) {
+      // The sizes are already checked above.
+      metadataIndex++;
+    }
+    auto& parameterMetadata = metadata.GetParameters()[metadataIndex];
+
+    if (!parameterMetadata.IsOptional() || dynamic_cast<EmptyNode*>(parameter.get()) == nullptr) {
+      auto currentParentType = parentType;
+      parentType = StringToType(parameterMetadata.GetType());
+      parameter->Visit(*this);
+      parentType = currentParentType;
+      
+      const gd::String &expectedParameterType = parameterMetadata.GetType();
+      if (gd::ParameterMetadata::IsExpression(
+          ExpressionValidator::variableTypeString, expectedParameterType)) {
+        if (dynamic_cast<IdentifierNode *>(parameter.get()) == nullptr
+         && dynamic_cast<VariableNode *>(parameter.get()) == nullptr) {
+          RaiseError(
+                  "malformed_variable_parameter",
+                  _("A variable name was expected but something else was "
+                    "written. Enter just the name of the variable for this "
+                    "parameter."),
+                parameter->location);
+        }
+      }
+      else if (gd::ParameterMetadata::IsObject(expectedParameterType)) {
+        if (dynamic_cast<IdentifierNode *>(parameter.get()) == nullptr) {
+          RaiseError(
+                  "malformed_object_parameter",
+                  _("An object name was expected but something else was "
+                    "written. Enter just the name of the object for this "
+                    "parameter."),
+                parameter->location);
+        }
+      }
+      // String and number are already checked in children.
+      else if (!gd::ParameterMetadata::IsExpression(
+               ExpressionValidator::numberTypeString, expectedParameterType)
+            && !gd::ParameterMetadata::IsExpression(
+              ExpressionValidator::stringTypeString, expectedParameterType)) {
+        RaiseError(
+                "unknown_parameter_type",
+                _("This function is improperly set up. Reach out to the "
+                  "extension developer or a GDevelop maintainer to fix "
+                  "this issue"),
+                parameter->location);
+      }
+    }
+    metadataIndex++;
+  }
+  return returnType;
+}
+
+  // TODO factorize in a file with an enum and helpers?
+  const gd::String ExpressionValidator::unknownTypeString = "unknown";
+  const gd::String ExpressionValidator::numberTypeString = "number";
+  const gd::String ExpressionValidator::stringTypeString = "string";
+  const gd::String ExpressionValidator::numberOrStringTypeString = "number|string";
+  const gd::String ExpressionValidator::variableTypeString = "variable";
+  const gd::String ExpressionValidator::objectTypeString = "object";
+  const gd::String ExpressionValidator::emptyTypeString = "empty";
+
+  const gd::String &ExpressionValidator::TypeToString(Type type) {
+    switch (type) {
+      case Type::Unknown:
+      return unknownTypeString;
+      case Type::Number:
+      return numberTypeString;
+      case Type::String:
+      return stringTypeString;
+      case Type::NumberOrString:
+      return numberOrStringTypeString;
+      case Type::Variable:
+      return variableTypeString;
+      case Type::Object:
+      return objectTypeString;
+      case Type::Empty:
+      return emptyTypeString;
+    }
+    return unknownTypeString;
+  }
+
+  ExpressionValidator::Type ExpressionValidator::StringToType(const gd::String &type) {
+    if (type == ExpressionValidator::numberTypeString
+     || gd::ParameterMetadata::IsExpression(ExpressionValidator::numberTypeString, type)) {
+      return Type::Number;
+    }
+    if (type == ExpressionValidator::stringTypeString
+     || gd::ParameterMetadata::IsExpression(ExpressionValidator::stringTypeString, type)) {
+      return Type::String;
+    }
+    if (type == ExpressionValidator::numberOrStringTypeString) {
+      return Type::NumberOrString;
+    }
+    if (type == ExpressionValidator::variableTypeString
+     || gd::ParameterMetadata::IsExpression(ExpressionValidator::variableTypeString, type)) {
+      return Type::Variable;
+    }
+    if (type == ExpressionValidator::objectTypeString
+     || gd::ParameterMetadata::IsObject(type)) {
+      return Type::Object;
+    }
+    return Type::Unknown;
+  }
+}  // namespace gd

Core/GDCore/IDE/Events/ExpressionValidator.h

@@ -10,6 +10,10 @@
 #include <vector>
 #include "GDCore/Events/Parsers/ExpressionParser2Node.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
+#include "GDCore/Tools/MakeUnique.h"
+#include "GDCore/Tools/Localization.h"
+#include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
+
 namespace gd {
 class Expression;
 class ObjectsContainer;
@@ -28,15 +32,27 @@ namespace gd {
  */
 class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
  public:
-  ExpressionValidator(){};
+  ExpressionValidator(const gd::Platform &platform_,
+                      const gd::ObjectsContainer &globalObjectsContainer_,
+                      const gd::ObjectsContainer &objectsContainer_,
+                      const gd::String &rootType_)
+      : platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        parentType(StringToType(gd::ParameterMetadata::GetExpressionValueType(rootType_))),
+        childType(Type::Unknown) {};
   virtual ~ExpressionValidator(){};
 
   /**
    * \brief Helper function to check if a given node does not contain
    * any error.
    */
-  static bool HasNoErrors(gd::ExpressionNode& node) {
-    gd::ExpressionValidator validator;
+  static bool HasNoErrors(const gd::Platform &platform,
+                      const gd::ObjectsContainer &globalObjectsContainer,
+                      const gd::ObjectsContainer &objectsContainer,
+                      const gd::String &rootType,
+                      gd::ExpressionNode& node) {
+    gd::ExpressionValidator validator(platform, globalObjectsContainer, objectsContainer, rootType);
     node.Visit(validator);
     return validator.GetErrors().empty();
   }
@@ -56,52 +72,247 @@ class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
     node.expression->Visit(*this);
   }
   void OnVisitOperatorNode(OperatorNode& node) override {
-    node.leftHandSide->Visit(*this);
     ReportAnyError(node);
+    
+    node.leftHandSide->Visit(*this);
+    const Type leftType = childType;
+
+    if (leftType == Type::Number) {
+      if (node.op == ' ') {
+        RaiseError("syntax_error",
+            "No operator found. Did you forget to enter an operator (like +, -, "
+            "* or /) between numbers or expressions?", node.rightHandSide->location);
+      }
+    }
+    else if (leftType == Type::String) {
+      if (node.op == ' ') {
+        RaiseError("syntax_error",
+            "You must add the operator + between texts or expressions. For "
+            "example: \"Your name: \" + VariableString(PlayerName).", node.rightHandSide->location);
+      }
+      else if (node.op != '+') {
+      RaiseOperatorError(
+          _("You've used an operator that is not supported. Only + can be used "
+            "to concatenate texts."),
+            ExpressionParserLocation(node.leftHandSide->location.GetEndPosition() + 1, node.location.GetEndPosition()));
+      }
+    } else if (leftType == Type::Object) {
+      RaiseOperatorError(
+          _("Operators (+, -, /, *) can't be used with an object name. Remove "
+            "the operator."),
+            node.rightHandSide->location);
+    } else if (leftType == Type::Variable) {
+      RaiseOperatorError(
+          _("Operators (+, -, /, *) can't be used in variable names. Remove "
+            "the operator from the variable name."),
+            node.rightHandSide->location);
+    }
+
+    parentType = leftType;
     node.rightHandSide->Visit(*this);
+    const Type rightType = childType;
+
+    childType = leftType;
   }
   void OnVisitUnaryOperatorNode(UnaryOperatorNode& node) override {
     ReportAnyError(node);
     node.factor->Visit(*this);
+    const Type rightType = childType;
+
+    if (rightType == Type::Number) {
+      if (node.op != '+' && node.op != '-') {
+        // This is actually a dead code because the parser takes them as
+        // binary operations with an empty left side which makes as much sense.
+        RaiseTypeError(
+          _("You've used an \"unary\" operator that is not supported. Operator "
+            "should be "
+            "either + or -."),
+          node.location);
+      }
+    } else if (rightType == Type::String) {
+      RaiseTypeError(
+          _("You've used an operator that is not supported. Only + can be used "
+            "to concatenate texts, and must be placed between two texts (or "
+            "expressions)."),
+          node.location);
+    } else if (rightType == Type::Object) {
+      RaiseTypeError(
+          _("Operators (+, -) can't be used with an object name. Remove the "
+            "operator."),
+          node.location);
+    } else if (rightType == Type::Variable) {
+      RaiseTypeError(
+          _("Operators (+, -) can't be used in variable names. Remove "
+            "the operator from the variable name."),
+          node.location);
+    }
+  }
+  void OnVisitNumberNode(NumberNode& node) override {
+    ReportAnyError(node);
+    childType = Type::Number;
+    CheckType(parentType, childType, node.location);
+  }
+  void OnVisitTextNode(TextNode& node) override {
+    ReportAnyError(node);
+    childType = Type::String;
+    CheckType(parentType, childType, node.location);
   }
-  void OnVisitNumberNode(NumberNode& node) override { ReportAnyError(node); }
-  void OnVisitTextNode(TextNode& node) override { ReportAnyError(node); }
   void OnVisitVariableNode(VariableNode& node) override {
     ReportAnyError(node);
-    if (node.child) node.child->Visit(*this);
+    if (node.child) {
+      node.child->Visit(*this);
+    }
+    childType = Type::Variable;
+    CheckType(parentType, childType, node.location);
   }
   void OnVisitVariableAccessorNode(VariableAccessorNode& node) override {
     ReportAnyError(node);
-    if (node.child) node.child->Visit(*this);
+    if (node.child) {
+      node.child->Visit(*this);
+    }
   }
   void OnVisitVariableBracketAccessorNode(
       VariableBracketAccessorNode& node) override {
     ReportAnyError(node);
+
+    Type currentParentType = parentType;
+    parentType = Type::NumberOrString;
     node.expression->Visit(*this);
-    if (node.child) node.child->Visit(*this);
+    parentType = currentParentType;
+
+    if (node.child) {
+      node.child->Visit(*this);
+    }
   }
   void OnVisitIdentifierNode(IdentifierNode& node) override {
     ReportAnyError(node);
+    if (parentType == Type::String) {
+      RaiseTypeError(_("You must wrap your text inside double quotes "
+                            "(example: \"Hello world\")."),
+                          node.location);
+    }
+    else if (parentType == Type::Number) {
+      RaiseTypeError(
+          _("You must enter a number."), node.location);
+    }
+    else if (parentType == Type::NumberOrString) {
+      RaiseTypeError(
+          _("You must enter a number or a text, wrapped inside double quotes "
+            "(example: \"Hello world\")."),
+          node.location);
+    }
+    else if (parentType != Type::Object && parentType != Type::Variable) {
+      // It can't happen.
+      RaiseTypeError(
+          _("You've entered a name, but this type was expected:") + " " + TypeToString(parentType),
+          node.location);
+    }
+    childType = parentType;
   }
   void OnVisitObjectFunctionNameNode(ObjectFunctionNameNode& node) override {
     ReportAnyError(node);
   }
   void OnVisitFunctionCallNode(FunctionCallNode& node) override {
-    ReportAnyError(node);
-    for (auto& parameter : node.parameters) {
-      parameter->Visit(*this);
-    }
+    childType = ValidateFunction(node);
+  }
+  void OnVisitEmptyNode(EmptyNode& node) override {
+    ReportAnyError(node);
+    gd::String message;
+    if (parentType == Type::Number) {
+      message = _("You must enter a number or a valid expression call.");
+    } else if (parentType == Type::String) {
+      message = _(
+          "You must enter a text (between quotes) or a valid expression call.");
+    } else if (parentType == Type::Variable) {
+      message = _("You must enter a variable name.");
+    } else if (parentType == Type::Object) {
+      message = _("You must enter a valid object name.");
+    } else {
+      // It can't happen.
+      message = _("You must enter a valid expression.");
+    }
+    RaiseTypeError(message, node.location);
+    childType = Type::Empty;
   }
-  void OnVisitEmptyNode(EmptyNode& node) override { ReportAnyError(node); }
 
  private:
-  void ReportAnyError(ExpressionNode& node) {
+  enum Type {Unknown = 0, Number, String, NumberOrString, Variable, Object, Empty};
+  Type ValidateFunction(const gd::FunctionCallNode& function);
+
+  void ReportAnyError(const ExpressionNode& node) {
     if (node.diagnostic && node.diagnostic->IsError()) {
+      // Syntax errors are holden by the AST nodes.
+      // It's fine to give pointers on them as the AST live longer than errors
+      // handling.
       errors.push_back(node.diagnostic.get());
     }
   }
 
+  void RaiseError(const gd::String &type, 
+      const gd::String &message, const ExpressionParserLocation &location) {
+    auto diagnostic = gd::make_unique<ExpressionParserError>(
+        type, message, location);
+    errors.push_back(diagnostic.get());
+    // Errors found by the validator are not holden by the AST nodes.
+    // They must be owned by the validator to keep living while errors are
+    // handled by the caller.
+    supplementalErrors.push_back(std::move(diagnostic));
+  }
+
+  void RaiseTypeError(
+      const gd::String &message, const ExpressionParserLocation &location) {
+    RaiseError("type_error", message, location);
+  }
+
+  void RaiseOperatorError(
+      const gd::String &message, const ExpressionParserLocation &location) {
+    RaiseError("invalid_operator", message, location);
+  }
+
+  void CheckType(Type expect, Type actual, const ExpressionParserLocation &location) {
+    if (actual == Type::String) {
+      if (expect == Type::Number) {
+        RaiseTypeError(_("You entered a text, but a number was expected."),
+                           location);
+      }
+      else if (expect != Type::String && expect != Type::NumberOrString) {
+        RaiseTypeError(
+            _("You entered a text, but this type was expected:") + " " + TypeToString(expect),
+            location);
+      }
+    }
+    else if (actual == Type::Number) {
+      if (expect == Type::String) {
+        RaiseTypeError(
+            _("You entered a number, but a text was expected (in quotes)."),
+            location);
+      }
+      else if (expect != Type::Number && expect != Type::NumberOrString) {
+        RaiseTypeError(
+            _("You entered a number, but this type was expected:") + " " + TypeToString(expect),
+            location);
+      }
+    }
+  }
+
+  static Type StringToType(const gd::String &type);
+  static const gd::String &TypeToString(Type type);
+  static const gd::String unknownTypeString;
+  static const gd::String numberTypeString;
+  static const gd::String stringTypeString;
+  static const gd::String numberOrStringTypeString;
+  static const gd::String variableTypeString;
+  static const gd::String objectTypeString;
+  static const gd::String identifierTypeString;
+  static const gd::String emptyTypeString;
+
   std::vector<ExpressionParserDiagnostic*> errors;
+  std::vector<std::unique_ptr<ExpressionParserDiagnostic>> supplementalErrors;
+  Type childType;
+  Type parentType;
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
 };
 
 }  // namespace gd

Core/GDCore/IDE/Events/ExpressionVariableOwnerFinder.h

@@ -0,0 +1,172 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#ifndef GDCORE_EXPRESSIONVARIABLEOWNERFINDER_H
+#define GDCORE_EXPRESSIONVARIABLEOWNERFINDER_H
+
+#include <memory>
+#include <vector>
+#include "GDCore/Events/Parsers/ExpressionParser2Node.h"
+#include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
+#include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Extensions/Metadata/ObjectMetadata.h"
+#include "GDCore/Extensions/Metadata/ParameterMetadata.h"
+#include "GDCore/Project/Layout.h"  // For GetTypeOfObject and GetTypeOfBehavior
+#include "GDCore/Tools/Localization.h"
+
+namespace gd {
+class Expression;
+class ObjectsContainer;
+class Platform;
+class ParameterMetadata;
+class ExpressionMetadata;
+}  // namespace gd
+
+namespace gd {
+
+/**
+ * \brief Find the object name that should be used as a context of the
+ * expression or sub-expression that a given node represents.
+ *
+ * \see gd::ExpressionParser2
+ */
+class GD_CORE_API ExpressionVariableOwnerFinder : public ExpressionParser2NodeWorker {
+ public:
+
+  /**
+   * \brief Helper function to find the object name that should be used as a
+   * context of the expression or sub-expression that a given node represents.
+   */
+  static const gd::String GetObjectName(const gd::Platform &platform,
+                      const gd::ObjectsContainer &globalObjectsContainer,
+                      const gd::ObjectsContainer &objectsContainer,
+                      const gd::String& rootObjectName,
+                      gd::ExpressionNode& node) {
+    gd::ExpressionVariableOwnerFinder typeFinder(
+        platform, globalObjectsContainer, objectsContainer, rootObjectName);
+    node.Visit(typeFinder);
+    return typeFinder.GetObjectName();
+  }
+
+  virtual ~ExpressionVariableOwnerFinder(){};
+
+ protected:
+  ExpressionVariableOwnerFinder(const gd::Platform &platform_,
+                       const gd::ObjectsContainer &globalObjectsContainer_,
+                       const gd::ObjectsContainer &objectsContainer_,
+                       const gd::String& rootObjectName_)
+      : platform(platform_),
+        globalObjectsContainer(globalObjectsContainer_),
+        objectsContainer(objectsContainer_),
+        rootObjectName(rootObjectName_),
+        objectName(""),
+        variableNode(nullptr) {};
+
+  /**
+   * \brief Get all the errors
+   *
+   * No errors means that the expression is valid.
+   */
+  const gd::String &GetObjectName() {
+    return objectName;
+  };
+
+  void OnVisitSubExpressionNode(SubExpressionNode& node) override {}
+  void OnVisitOperatorNode(OperatorNode& node) override {}
+  void OnVisitUnaryOperatorNode(UnaryOperatorNode& node) override {}
+  void OnVisitNumberNode(NumberNode& node) override {}
+  void OnVisitTextNode(TextNode& node) override {}
+  void OnVisitVariableNode(VariableNode& node) override {
+    if (variableNode != nullptr) {
+      // This is not possible
+      return;
+    }
+    if (node.parent == nullptr) {
+      objectName = rootObjectName;
+      return;
+    }
+    variableNode = &node;
+    node.parent->Visit(*this);
+  }
+  void OnVisitVariableAccessorNode(VariableAccessorNode& node) override {}
+  void OnVisitIdentifierNode(IdentifierNode& node) override {
+    if (variableNode != nullptr) {
+      // This is not possible
+      return;
+    }
+    if (node.parent == nullptr) {
+      objectName = rootObjectName;
+      return;
+    }
+    // This node is not necessarily a variable node.
+    // It will be checked when visiting the FunctionCallNode.
+    variableNode = &node;
+    node.parent->Visit(*this);
+  }
+  void OnVisitEmptyNode(EmptyNode& node) override {}
+  void OnVisitObjectFunctionNameNode(ObjectFunctionNameNode& node) override {}
+  void OnVisitVariableBracketAccessorNode(
+      VariableBracketAccessorNode& node) override {}
+  void OnVisitFunctionCallNode(FunctionCallNode& functionCall) override {
+    if (variableNode == nullptr) {
+      return;
+    }
+    int parameterIndex = -1;
+    for (int i = 0; i < functionCall.parameters.size(); i++) {
+      if (functionCall.parameters.at(i).get() == variableNode) {
+        parameterIndex = i;
+        break;
+      }
+    }
+    if (parameterIndex < 0) {
+      return;
+    }
+    const gd::ParameterMetadata* parameterMetadata =
+        MetadataProvider::GetFunctionCallParameterMetadata(
+            platform, 
+            globalObjectsContainer,
+            objectsContainer,
+            functionCall,
+            parameterIndex);
+    if (parameterMetadata == nullptr
+     || parameterMetadata->GetType() != "objectvar") {
+      return;
+    }
+
+    // The object on which the function is called is returned if no previous
+    // parameters are objects.
+    objectName = functionCall.objectName;
+    for (int previousIndex = parameterIndex - 1; previousIndex >= 0; previousIndex--) {
+      const gd::ParameterMetadata* previousParameterMetadata =
+          MetadataProvider::GetFunctionCallParameterMetadata(
+              platform, 
+              globalObjectsContainer,
+              objectsContainer,
+              functionCall,
+              previousIndex);
+      if (previousParameterMetadata != nullptr
+      && gd::ParameterMetadata::IsObject(previousParameterMetadata->GetType())) {
+        auto previousParameterNode = functionCall.parameters[previousIndex].get();
+        IdentifierNode* objectNode = dynamic_cast<IdentifierNode*>(previousParameterNode);
+        objectName = objectNode->identifierName;
+        return;
+      }
+    }
+  }
+
+ private:
+  gd::String objectName;
+  gd::ExpressionNode *variableNode;
+
+  const gd::Platform &platform;
+  const gd::ObjectsContainer &globalObjectsContainer;
+  const gd::ObjectsContainer &objectsContainer;
+  const gd::String &rootObjectName;
+};
+
+}  // namespace gd
+
+#endif  // GDCORE_EXPRESSIONVARIABLEOWNERFINDER_H

Core/GDCore/IDE/Events/ExpressionsParameterMover.cpp

@@ -11,7 +11,6 @@
 
 #include "GDCore/Events/Event.h"
 #include "GDCore/Events/EventsList.h"
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
@@ -146,17 +145,9 @@ bool ExpressionsParameterMover::DoVisitInstruction(gd::Instruction& instruction,
                             pNb < instruction.GetParametersCount();
        ++pNb) {
     const gd::String& type = metadata.parameters[pNb].type;
-    const gd::String& expression =
-        instruction.GetParameter(pNb).GetPlainString();
+    const gd::Expression& expression = instruction.GetParameter(pNb);
 
-    gd::ExpressionParser2 parser(
-        platform, GetGlobalObjectsContainer(), GetObjectsContainer());
-
-    auto node = gd::ParameterMetadata::IsExpression("number", type)
-                    ? parser.ParseExpression("number", expression)
-                    : (gd::ParameterMetadata::IsExpression("string", type)
-                           ? parser.ParseExpression("string", expression)
-                           : std::unique_ptr<gd::ExpressionNode>());
+    auto node = expression.GetRootNode();
     if (node) {
       ExpressionParameterMover mover(GetGlobalObjectsContainer(),
                                      GetObjectsContainer(),

Core/GDCore/IDE/Events/ExpressionsRenamer.cpp

@@ -11,7 +11,6 @@
 
 #include "GDCore/Events/Event.h"
 #include "GDCore/Events/EventsList.h"
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
@@ -156,18 +155,9 @@ bool ExpressionsRenamer::DoVisitInstruction(gd::Instruction& instruction,
   for (std::size_t pNb = 0; pNb < metadata.parameters.size() &&
                             pNb < instruction.GetParametersCount();
        ++pNb) {
-    const gd::String& type = metadata.parameters[pNb].type;
-    const gd::String& expression =
-        instruction.GetParameter(pNb).GetPlainString();
+    const gd::Expression& expression = instruction.GetParameter(pNb);
 
-    gd::ExpressionParser2 parser(
-        platform, GetGlobalObjectsContainer(), GetObjectsContainer());
-
-    auto node = gd::ParameterMetadata::IsExpression("number", type)
-                    ? parser.ParseExpression("number", expression)
-                    : (gd::ParameterMetadata::IsExpression("string", type)
-                           ? parser.ParseExpression("string", expression)
-                           : std::unique_ptr<gd::ExpressionNode>());
+    auto node = expression.GetRootNode();
     if (node) {
       ExpressionFunctionRenamer renamer(GetGlobalObjectsContainer(),
                                         GetObjectsContainer(),

Core/GDCore/IDE/Events/UsedExtensionsFinder.cpp

@@ -1,10 +1,10 @@
 #include "UsedExtensionsFinder.h"
 
 #include "GDCore/Events/Instruction.h"
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/PlatformExtension.h"
 #include "GDCore/IDE/WholeProjectRefactorer.h"
+#include "GDCore/IDE/Events/ExpressionTypeFinder.h"
 #include "GDCore/Project/BehaviorContent.h"
 #include "GDCore/Project/Object.h"
 #include "GDCore/Project/Project.h"
@@ -54,13 +54,12 @@ bool UsedExtensionsFinder::DoVisitInstruction(gd::Instruction& instruction,
         metadata.GetMetadata().GetParameter(i).GetType();
     i++;
 
-    if (gd::ParameterMetadata::IsExpression("string", parameterType) ||
-        gd::ParameterMetadata::IsExpression("number", parameterType)) {
-      gd::ExpressionParser2 parser(project.GetCurrentPlatform(),
-                                   GetGlobalObjectsContainer(),
-                                   GetObjectsContainer());
-      parser.ParseExpression(parameterType, expression.GetPlainString())
-          ->Visit(*this);
+    if (gd::ParameterMetadata::IsExpression("string", parameterType)) {
+      rootType = "string";
+      expression.GetRootNode()->Visit(*this);
+    } else if (gd::ParameterMetadata::IsExpression("number", parameterType)) {
+      rootType = "number";
+      expression.GetRootNode()->Visit(*this);
     } else if (gd::ParameterMetadata::IsExpression("variable", parameterType))
       usedExtensions.insert("BuiltinVariables");
   }
@@ -113,7 +112,8 @@ void UsedExtensionsFinder::OnVisitVariableBracketAccessorNode(
 
 // Add extensions bound to Objects/Behaviors/Functions
 void UsedExtensionsFinder::OnVisitIdentifierNode(IdentifierNode& node) {
-  if (gd::ParameterMetadata::IsObject(node.type)) {
+  auto type = gd::ExpressionTypeFinder::GetType(project.GetCurrentPlatform(), GetGlobalObjectsContainer(), GetObjectsContainer(), rootType, node);
+  if (gd::ParameterMetadata::IsObject(type)) {
     usedExtensions.insert(gd::MetadataProvider::GetExtensionAndObjectMetadata(
                               project.GetCurrentPlatform(), node.identifierName)
                               .GetExtension()

Core/GDCore/IDE/Events/UsedExtensionsFinder.h

@@ -31,6 +31,7 @@ class GD_CORE_API UsedExtensionsFinder
  private:
   UsedExtensionsFinder(gd::Project& project_) : project(project_){};
   gd::Project& project;
+  gd::String rootType;
   std::set<gd::String> usedExtensions;
 
   // Object Visitor

Core/GDCore/IDE/EventsFunctionTools.cpp

@@ -18,7 +18,7 @@
 namespace gd {
 
 void EventsFunctionTools::FreeEventsFunctionToObjectsContainer(
-    gd::Project& project,
+    const gd::Project& project,
     const gd::EventsFunction& eventsFunction,
     gd::ObjectsContainer& outputGlobalObjectsContainer,
     gd::ObjectsContainer& outputObjectsContainer) {
@@ -36,7 +36,7 @@ void EventsFunctionTools::FreeEventsFunctionToObjectsContainer(
 }
 
 void EventsFunctionTools::BehaviorEventsFunctionToObjectsContainer(
-    gd::Project& project,
+    const gd::Project& project,
     const gd::EventsBasedBehavior& eventsBasedBehavior,
     const gd::EventsFunction& eventsFunction,
     gd::ObjectsContainer& outputGlobalObjectsContainer,

Core/GDCore/IDE/EventsFunctionTools.h

@@ -32,7 +32,7 @@ class GD_CORE_API EventsFunctionTools {
    * generation for example.
    */
   static void FreeEventsFunctionToObjectsContainer(
-      gd::Project& project,
+      const gd::Project& project,
       const gd::EventsFunction& eventsFunction,
       gd::ObjectsContainer& outputGlobalObjectsContainer,
       gd::ObjectsContainer& outputObjectsContainer);
@@ -46,7 +46,7 @@ class GD_CORE_API EventsFunctionTools {
    * generation for example.
    */
   static void BehaviorEventsFunctionToObjectsContainer(
-      gd::Project& project,
+      const gd::Project& project,
       const gd::EventsBasedBehavior& eventsBasedBehavior,
       const gd::EventsFunction& eventsFunction,
       gd::ObjectsContainer& outputGlobalObjectsContainer,

Core/GDCore/IDE/Project/ArbitraryResourceWorker.cpp

@@ -126,9 +126,10 @@ class ResourceWorkerInEventsWorker : public ArbitraryEventsWorker {
         instruction.GetParameters(),
         metadata.GetParameters(),
         [this, &instruction](const gd::ParameterMetadata& parameterMetadata,
-                             const gd::String& parameterValue,
+                             const gd::Expression& parameterExpression,
                              size_t parameterIndex,
                              const gd::String& lastObjectName) {
+          const String& parameterValue = parameterExpression.GetPlainString();
           if (parameterMetadata.GetType() ==
               "police") {  // Should be renamed fontResource
             gd::String updatedParameterValue = parameterValue;

Core/GDCore/Project/Layout.cpp

@@ -444,7 +444,7 @@ gd::String GD_CORE_API GetTypeOfObject(const gd::ObjectsContainer& project,
     type = project.GetObject(name).GetType();
 
   // Search in groups
-  if (searchInGroups) {
+  else if (searchInGroups) {
     for (std::size_t i = 0; i < layout.GetObjectGroups().size(); ++i) {
       if (layout.GetObjectGroups()[i].GetName() == name) {
         // A group has the name searched
@@ -505,18 +505,16 @@ gd::String GD_CORE_API GetTypeOfBehavior(const gd::ObjectsContainer& project,
                                          gd::String name,
                                          bool searchInGroups) {
   for (std::size_t i = 0; i < layout.GetObjectsCount(); ++i) {
-    vector<gd::String> behaviors = layout.GetObject(i).GetAllBehaviorNames();
-    for (std::size_t j = 0; j < behaviors.size(); ++j) {
-      if (layout.GetObject(i).GetBehavior(behaviors[j]).GetName() == name)
-        return layout.GetObject(i).GetBehavior(behaviors[j]).GetTypeName();
+    const auto &object = layout.GetObject(i);
+    if (object.HasBehaviorNamed(name)) {
+      return object.GetBehavior(name).GetTypeName();
     }
   }
 
   for (std::size_t i = 0; i < project.GetObjectsCount(); ++i) {
-    vector<gd::String> behaviors = project.GetObject(i).GetAllBehaviorNames();
-    for (std::size_t j = 0; j < behaviors.size(); ++j) {
-      if (project.GetObject(i).GetBehavior(behaviors[j]).GetName() == name)
-        return project.GetObject(i).GetBehavior(behaviors[j]).GetTypeName();
+    const auto &object = project.GetObject(i);
+    if (object.HasBehaviorNamed(name)) {
+      return object.GetBehavior(name).GetTypeName();
     }
   }
 

Core/GDCore/Project/Object.cpp

@@ -86,7 +86,7 @@ std::map<gd::String, gd::PropertyDescriptor> Object::GetProperties() const {
   return nothing;
 }
 
-gd::BehaviorContent* Object::AddNewBehavior(gd::Project& project,
+gd::BehaviorContent* Object::AddNewBehavior(const gd::Project& project,
                                             const gd::String& type,
                                             const gd::String& name) {
   const gd::BehaviorMetadata& behaviorMetadata =

Core/GDCore/Project/Object.h

@@ -242,7 +242,7 @@ class GD_CORE_API Object {
    * \return A pointer to the newly added behavior content. NULL if the creation
    * failed.
    */
-  gd::BehaviorContent* AddNewBehavior(gd::Project& project,
+  gd::BehaviorContent* AddNewBehavior(const gd::Project& project,
                                       const gd::String& type,
                                       const gd::String& name);
 #endif

Core/GDCore/Project/ObjectsContainer.cpp

@@ -76,7 +76,7 @@ std::size_t ObjectsContainer::GetObjectsCount() const {
   return initialObjects.size();
 }
 #if defined(GD_IDE_ONLY)
-gd::Object& ObjectsContainer::InsertNewObject(gd::Project& project,
+gd::Object& ObjectsContainer::InsertNewObject(const gd::Project& project,
                                               const gd::String& objectType,
                                               const gd::String& name,
                                               std::size_t position) {

Core/GDCore/Project/ObjectsContainer.h

@@ -94,7 +94,7 @@ class GD_CORE_API ObjectsContainer {
    * \note The object is created using the project's current platform.
    * \return A reference to the object in the list.
    */
-  gd::Object& InsertNewObject(gd::Project& project,
+  gd::Object& InsertNewObject(const gd::Project& project,
                               const gd::String& objectType,
                               const gd::String& name,
                               std::size_t position);

Core/GDCore/Project/ResourcesManager.h

@@ -60,7 +60,7 @@ class GD_CORE_API Resource {
    * \see gd::Resource::GetFile
    * \see gd::Resource::SetFile
    */
-  virtual bool UseFile() { return false; }
+  virtual bool UseFile() const { return false; }
 
   /**
    * \brief Return, if applicable, the String containing the file used by the
@@ -184,7 +184,7 @@ class GD_CORE_API ImageResource : public Resource {
    */
   virtual void SetFile(const gd::String& newFile) override;
 
-  virtual bool UseFile() override { return true; }
+  virtual bool UseFile() const override { return true; }
 
   std::map<gd::String, gd::PropertyDescriptor> GetProperties() const override;
   bool UpdateProperty(const gd::String& name, const gd::String& value) override;
@@ -234,7 +234,7 @@ class GD_CORE_API AudioResource : public Resource {
   virtual const gd::String& GetFile() const override { return file; };
   virtual void SetFile(const gd::String& newFile) override;
 
-  virtual bool UseFile() override { return true; }
+  virtual bool UseFile() const override { return true; }
 
   std::map<gd::String, gd::PropertyDescriptor> GetProperties() const override;
   bool UpdateProperty(const gd::String& name, const gd::String& value) override;
@@ -286,7 +286,7 @@ class GD_CORE_API FontResource : public Resource {
   virtual const gd::String& GetFile() const override { return file; };
   virtual void SetFile(const gd::String& newFile) override;
 
-  virtual bool UseFile() override { return true; }
+  virtual bool UseFile() const override { return true; }
   void SerializeTo(SerializerElement& element) const override;
 
   void UnserializeFrom(const SerializerElement& element) override;
@@ -312,7 +312,7 @@ class GD_CORE_API VideoResource : public Resource {
   virtual const gd::String& GetFile() const override { return file; };
   virtual void SetFile(const gd::String& newFile) override;
 
-  virtual bool UseFile() override { return true; }
+  virtual bool UseFile() const override { return true; }
   void SerializeTo(SerializerElement& element) const override;
 
   void UnserializeFrom(const SerializerElement& element) override;
@@ -338,7 +338,7 @@ class GD_CORE_API JsonResource : public Resource {
   virtual const gd::String& GetFile() const override { return file; };
   virtual void SetFile(const gd::String& newFile) override;
 
-  virtual bool UseFile() override { return true; }
+  virtual bool UseFile() const override { return true; }
 
   std::map<gd::String, gd::PropertyDescriptor> GetProperties() const override;
   bool UpdateProperty(const gd::String& name, const gd::String& value) override;
@@ -379,7 +379,7 @@ class GD_CORE_API BitmapFontResource : public Resource {
   virtual const gd::String& GetFile() const override { return file; };
   virtual void SetFile(const gd::String& newFile) override;
 
-  virtual bool UseFile() override { return true; }
+  virtual bool UseFile() const override { return true; }
   void SerializeTo(SerializerElement& element) const override;
 
   void UnserializeFrom(const SerializerElement& element) override;

Core/GDCore/TinyXml/tinyxmlparser.cpp

@@ -354,7 +354,7 @@ const char* TiXmlBase::SkipWhiteSpace( const char* p, TiXmlEncoding encoding )
 	}
 	else
 	{
-		while ( *p && IsWhiteSpace( *p ) || *p == '\n' || *p =='\r' )
+		while ( (*p && IsWhiteSpace( *p )) || *p == '\n' || *p =='\r' )
 			++p;
 	}
 

Core/tests/DummyPlatform.cpp

@@ -197,6 +197,17 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
       .AddParameter("object", _("Object 2 parameter"))
       .AddParameter("objectvar", _("Variable for object 2"))
       .SetFunctionName("getStringWith2ObjectParamAnd2ObjectVarParam");
+  extension
+      ->AddStrExpression(
+          "GetStringWith1ObjectParamAnd2ObjectVarParam",
+          "Get string with 2 objectvar param one from the same object param",
+          "",
+          "",
+          "")
+      .AddParameter("object", _("Object 1 parameter"))
+      .AddParameter("objectvar", _("Variable for object 1"))
+      .AddParameter("objectvar", _("Variable for object 2"))
+      .SetFunctionName("getStringWith1ObjectParamAnd2ObjectVarParam");
 
   auto& object = extension->AddObject<gd::Object>(
       "Sprite", "Dummy Sprite", "Dummy sprite object", "");

Core/tests/ExpressionCodeGenerator.cpp

@@ -32,7 +32,7 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
   group.AddObject("MyOtherSpriteObject");
   group.AddObject("MyFakeObjectWithUnsupportedCapability");
 
-  gd::ExpressionParser2 parser(platform, project, layout1);
+  gd::ExpressionParser2 parser;
 
   unsigned int maxDepth = 0;
   gd::EventsCodeGenerationContext context(&maxDepth);
@@ -40,8 +40,10 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
 
   SECTION("Valid text generation") {
     {
-      auto node = parser.ParseExpression("string", "\"hello world\"");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      auto node = parser.ParseExpression("\"hello world\"");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -49,8 +51,10 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
       REQUIRE(expressionCodeGenerator.GetOutput() == "\"hello world\"");
     }
     {
-      auto node = parser.ParseExpression("string", "\"hello\"  +   \"world\" ");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      auto node = parser.ParseExpression("\"hello\"  +   \"world\" ");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -59,8 +63,10 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
     }
     {
       auto node = parser.ParseExpression(
-          "string", "\"{\\\"hello\\\": \\\"world \\\\\\\" \\\"}\"");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+          "\"{\\\"hello\\\": \\\"world \\\\\\\" \\\"}\"");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -72,8 +78,10 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
 
   SECTION("Valid number generation") {
     {
-      auto node = parser.ParseExpression("number", "12.45");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      auto node = parser.ParseExpression("12.45");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -85,8 +93,10 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
   SECTION("Invalid operators generation") {
     // TODO: Should any error return directly 0 or ""?
     {
-      auto node = parser.ParseExpression("number", "12.45 +");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      auto node = parser.ParseExpression("12.45 +");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -94,8 +104,10 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
       REQUIRE(expressionCodeGenerator.GetOutput() == "12.45 + 0");
     }
     {
-      auto node = parser.ParseExpression("number", "12.45 * *");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      auto node = parser.ParseExpression("12.45 * *");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -106,16 +118,20 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
 
   SECTION("Valid unary operator generation") {
     {
-      auto node = parser.ParseExpression("number", "-12.45");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      auto node = parser.ParseExpression("-12.45");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
       REQUIRE(node);
       node->Visit(expressionCodeGenerator);
       REQUIRE(expressionCodeGenerator.GetOutput() == "-(12.45)");
     }
     {
-      auto node = parser.ParseExpression("number", "12.5 + -2.  /   (.3)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      auto node = parser.ParseExpression("12.5 + -2.  /   (.3)");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
       REQUIRE(node);
       node->Visit(expressionCodeGenerator);
@@ -124,20 +140,24 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
   }
 
   SECTION("Valid function calls") {
-    {
+    SECTION("without parameter") {
       auto node =
-          parser.ParseExpression("number", " 1 /  MyExtension::GetNumber()");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+          parser.ParseExpression(" 1 /  MyExtension::GetNumber()");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
       node->Visit(expressionCodeGenerator);
       REQUIRE(expressionCodeGenerator.GetOutput() == "1 / getNumber()");
     }
-    {
+    SECTION("number and string parameters") {
       auto node = parser.ParseExpression(
-          "number", "MyExtension::GetNumberWith2Params(12, \"hello world\")");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+          "MyExtension::GetNumberWith2Params(12, \"hello world\")");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -145,12 +165,13 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
       REQUIRE(expressionCodeGenerator.GetOutput() ==
               "getNumberWith2Params(12, \"hello world\")");
     }
-    {
+    SECTION("nested function call") {
       auto node =
-          parser.ParseExpression("number",
-                                 "MyExtension::GetNumberWith2Params("
+          parser.ParseExpression("MyExtension::GetNumberWith2Params("
                                  "MyExtension::GetNumber(), \"hello world\")");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -158,10 +179,12 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
       REQUIRE(expressionCodeGenerator.GetOutput() ==
               "getNumberWith2Params(getNumber(), \"hello world\")");
     }
-    {
+    SECTION("object function") {
       auto node =
-          parser.ParseExpression("number", "MySpriteObject.GetObjectNumber()");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+          parser.ParseExpression("MySpriteObject.GetObjectNumber()");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -169,11 +192,12 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
       REQUIRE(expressionCodeGenerator.GetOutput() ==
               "MySpriteObject.getObjectNumber() ?? 0");
     }
-    {
+    SECTION("object function with nested free function") {
       auto node = parser.ParseExpression(
-          "string",
           "MySpriteObject.GetObjectStringWith1Param(MyExtension::GetNumber())");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -183,22 +207,11 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
     }
   }
   SECTION("Valid function calls with optional arguments") {
-    {
-      auto node =
-          parser.ParseExpression("number", "MyExtension::MouseX(\"layer1\",)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
-                                                          context);
-
-      REQUIRE(node);
-      node->Visit(expressionCodeGenerator);
-      REQUIRE(expressionCodeGenerator.GetOutput() ==
-              "getMouseX(\"\", \"layer1\", 0)");
-      // (first argument is the currentScene)
-    }
-    {
-      auto node = parser.ParseExpression("number",
-                                         "MyExtension::MouseX(\"layer1\",2+2)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+    SECTION("with optional parameter set") {
+      auto node = parser.ParseExpression("MyExtension::MouseX(\"layer1\",2+2)");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -207,13 +220,39 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
               "getMouseX(\"\", \"layer1\", 2 + 2)");
       // (first argument is the currentScene)
     }
-  }
-  SECTION(
-      "Valid function calls (deprecated way of specifying optional "
-      "arguments)") {
-    {
-      auto node = parser.ParseExpression("number", "MyExtension::MouseX(,)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+    SECTION("with last optional parameter omit") {
+      auto node =
+          parser.ParseExpression("MyExtension::MouseX(\"layer1\")");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
+                                                          context);
+
+      REQUIRE(node);
+      node->Visit(expressionCodeGenerator);
+      REQUIRE(expressionCodeGenerator.GetOutput() ==
+              "getMouseX(\"\", \"layer1\", 0)");
+      // (first argument is the currentScene)
+    }
+    SECTION("with last optional parameter omit (deprecated way)") {
+      auto node =
+          parser.ParseExpression("MyExtension::MouseX(\"layer1\",)");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
+                                                          context);
+
+      REQUIRE(node);
+      node->Visit(expressionCodeGenerator);
+      REQUIRE(expressionCodeGenerator.GetOutput() ==
+              "getMouseX(\"\", \"layer1\", 0)");
+      // (first argument is the currentScene)
+    }
+    SECTION("with explicit comma (deprecated way)") {
+      auto node = parser.ParseExpression("MyExtension::MouseX(,)");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -223,15 +262,17 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
       // (first argument is the currentScene)
     }
   }
+
   SECTION("Invalid function calls") {
-    {
+    SECTION("unknown identifier in parameters") {
       auto node =
-          parser.ParseExpression("string",
-                                 "MySpriteObject.GetObjectStringWith3Param("
+          parser.ParseExpression("MySpriteObject.GetObjectStringWith3Param("
                                  "MySpriteObject.GetObjectNumber() / 2.3, "
                                  "MySpriteObject.GetObjectStringWith1Param("
                                  "MyExtension::GetNumber()), test)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -243,33 +284,38 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
               "/* Error during generation, unrecognized identifier type: "
               "unknown with value test */ \"test\") ?? \"\"");
     }
-    {
-      auto node = parser.ParseExpression(
-          "number",
-          "MyExtension::GetNumberWith2Params(MyExtension::GetNumber())");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
-                                                          context);
+    SECTION("missing parameter") {
+      {
+        auto node = parser.ParseExpression(
+            "MyExtension::GetNumberWith2Params(MyExtension::GetNumber())");
+        gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                            "",
+                                                            codeGenerator,
+                                                            context);
 
-      REQUIRE(node);
-      node->Visit(expressionCodeGenerator);
-      REQUIRE(expressionCodeGenerator.GetOutput() ==
-              "getNumberWith2Params(getNumber(), /* Error during generation, "
-              "parameter not existing in the nodes */ \"\")");
+        REQUIRE(node);
+        node->Visit(expressionCodeGenerator);
+        REQUIRE(expressionCodeGenerator.GetOutput() ==
+                "getNumberWith2Params(getNumber(), /* Error during generation, "
+                "parameter not existing in the nodes */ \"\")");
+      }
+      {
+        // Using GenerateExpressionCode, the default value of 0 should be returned
+        // as expression is invalid.
+        REQUIRE(
+            gd::ExpressionCodeGenerator::GenerateExpressionCode(
+                codeGenerator,
+                context,
+                "number",
+                "MyExtension::GetNumberWith2Params(MyExtension::GetNumber())") ==
+            "0");
+      }
     }
-    {
-      // Using GenerateExpressionCode, the default value of 0 should be returned
-      // as expression is invalid.
-      REQUIRE(
-          gd::ExpressionCodeGenerator::GenerateExpressionCode(
-              codeGenerator,
-              context,
-              "number",
-              "MyExtension::GetNumberWith2Params(MyExtension::GetNumber())") ==
-          "0");
-    }
-    {
-      auto node = parser.ParseExpression("number", "MyExtension::Idontexist()");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+    SECTION("unknown function") {
+      auto node = parser.ParseExpression("MyExtension::Idontexist()");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -278,11 +324,12 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
               "/* Error during generation, function not found: "
               "MyExtension::Idontexist */ 0");
     }
-    {
-      auto node = parser.ParseExpression("number",
-                                         "MyExtension::GetNumberWith2Params(1, "
+    SECTION("too much parameters") {
+      auto node = parser.ParseExpression("MyExtension::GetNumberWith2Params(1, "
                                          "\"2\", MyExtension::GetNumber())");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -291,13 +338,14 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
               "getNumberWith2Params(1, \"2\")");
     }
   }
-  SECTION("Invalid function calls (capabilities)") {
-    {
+  SECTION("function calls (capabilities)") {
+    SECTION("supported capability") {
       // Capability is supported, so the expression is valid.
       auto node = parser.ParseExpression(
-          "string",
           "MySpriteObject.GetSomethingRequiringEffectCapability(123)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -306,26 +354,29 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
           expressionCodeGenerator.GetOutput() ==
           "MySpriteObject.getSomethingRequiringEffectCapability(123) ?? \"\"");
     }
-    {
+    SECTION("unsupported capability") {
       // Capability is not supported, so the expression is not even valid.
       auto node =
-          parser.ParseExpression("string",
-                                 "MyFakeObjectWithUnsupportedCapability."
+          parser.ParseExpression("MyFakeObjectWithUnsupportedCapability."
                                  "GetSomethingRequiringEffectCapability(123)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
       node->Visit(expressionCodeGenerator);
       REQUIRE(expressionCodeGenerator.GetOutput() == "\"\"");
     }
-    {
+    SECTION("group with partial support") {
       // We use a group, capability is supported only by one object of the
       // group. The expression itself is valid, but code generation should skip
       // the objects with unsupported capability.
       auto node = parser.ParseExpression(
-          "string", "AllObjects.GetSomethingRequiringEffectCapability(123)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+          "AllObjects.GetSomethingRequiringEffectCapability(123)");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);
@@ -336,51 +387,87 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
           "MySpriteObject.getSomethingRequiringEffectCapability(123) ?? \"\"");
     }
   }
+  SECTION("Function name") {
+    auto node =
+        parser.ParseExpression("MySpriteObject.GetObjectNumber");
+    gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                        "",
+                                                        codeGenerator,
+                                                        context);
+
+    REQUIRE(node);
+    node->Visit(expressionCodeGenerator);
+    REQUIRE(expressionCodeGenerator.GetOutput() == "0");
+  }
   SECTION("Invalid variables") {
-    {
-      // Test an empty expression
+    SECTION("empty variable") {
       REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
                   codeGenerator, context, "scenevar", "") == "fakeBadVariable");
     }
-    {
-      // Test a unary operator
+    SECTION("only an unary operator") {
       REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
                   codeGenerator, context, "objectvar", "-") ==
               "fakeBadVariable");
     }
-    {
-      // Test an operator
+    SECTION("only a binary operator") {
       REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
                   codeGenerator, context, "globalvar", "/") ==
               "fakeBadVariable");
     }
   }
   SECTION("Invalid variables, using operators") {
-    {
-      // Test a unary operator
+    SECTION("unary operation") {
       REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
                   codeGenerator, context, "objectvar", "-(var1)") ==
               "fakeBadVariable");
     }
-    {
-      // Test an operator
+    SECTION("binary operation") {
       REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
                   codeGenerator, context, "globalvar", "var1+var2") ==
               "fakeBadVariable");
     }
-    {
-      // Test multiple operators
+    SECTION("multiple operation") {
       REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
                   codeGenerator, context, "globalvar", "var1/var2/var3/var4") ==
               "fakeBadVariable");
     }
   }
+  SECTION("Valid variables") {
+    SECTION("simple variable") {
+      REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
+                  codeGenerator, context, "scenevar", "myVariable", "")
+              == "getLayoutVariable(myVariable)");
+    }
+    SECTION("child dot accessor") {
+      REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
+                  codeGenerator, context, "scenevar", "myVariable.myChild", "")
+              == "getLayoutVariable(myVariable).getChild(\"myChild\")");
+    }
+    SECTION("2 children") {
+      REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
+                  codeGenerator, context, "scenevar", "myVariable.child1.child2", "")
+              == "getLayoutVariable(myVariable).getChild(\"child1\").getChild(\"child2\")");
+    }
+    SECTION("bracket access") {
+      REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
+                  codeGenerator, context, "scenevar", "myVariable[ \"hello\" + "
+            "\"world\" ]", "")
+              == "getLayoutVariable(myVariable).getChild(\"hello\" + \"world\")");
+    }
+    SECTION("object variable") {
+      REQUIRE(gd::ExpressionCodeGenerator::GenerateExpressionCode(
+                  codeGenerator, context, "objectvar", "myVariable", "MySpriteObject")
+              == "getVariableForObject(MySpriteObject, myVariable)");
+    }
+  }
   SECTION("Valid function calls with variables") {
     SECTION("Simple access") {
-      {
+      SECTION("Scene variable") {
         auto node = parser.ParseExpression(
-            "number", "MyExtension::GetVariableAsNumber(myVariable)");
-        gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+            "MyExtension::GetVariableAsNumber(myVariable)");
+        gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                            "",
+                                                            codeGenerator,
                                                             context);
 
         REQUIRE(node);
@@ -388,11 +475,12 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
         REQUIRE(expressionCodeGenerator.GetOutput() ==
                 "returnVariable(getLayoutVariable(myVariable))");
       }
-      {
+      SECTION("Global variable") {
         auto node = parser.ParseExpression(
-            "number",
             "MyExtension::GetGlobalVariableAsNumber(myGlobalVariable)");
-        gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+        gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                            "",
+                                                            codeGenerator,
                                                             context);
 
         REQUIRE(node);
@@ -400,13 +488,76 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
         REQUIRE(expressionCodeGenerator.GetOutput() ==
                 "returnVariable(getProjectVariable(myGlobalVariable))");
       }
+      SECTION("Variables on different objects") {
+        auto node = parser.ParseExpression(
+            "MyExtension::GetStringWith2ObjectParamAnd2ObjectVarParam("
+            "MySpriteObject, myVariable, MyOtherSpriteObject, myOtherVariable)");
+        gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                            "",
+                                                            codeGenerator,
+                                                            context);
+
+        REQUIRE(node);
+        node->Visit(expressionCodeGenerator);
+        REQUIRE(expressionCodeGenerator.GetOutput() ==
+            "getStringWith2ObjectParamAnd2ObjectVarParam(fakeObjectListOf_MySpriteObject, "
+            "getVariableForObject(MySpriteObject, myVariable), "
+            "fakeObjectListOf_MyOtherSpriteObject, "
+            "getVariableForObject(MyOtherSpriteObject, myOtherVariable))");
+      }
+      SECTION("Variables on the same object") {
+        auto node = parser.ParseExpression(
+            "MyExtension::GetStringWith1ObjectParamAnd2ObjectVarParam("
+            "MySpriteObject, myVariable, myOtherVariable)");
+        gd::ExpressionCodeGenerator expressionCodeGenerator("string",
+                                                            "",
+                                                            codeGenerator,
+                                                            context);
+
+        REQUIRE(node);
+        node->Visit(expressionCodeGenerator);
+        REQUIRE(expressionCodeGenerator.GetOutput() ==
+            "getStringWith1ObjectParamAnd2ObjectVarParam(fakeObjectListOf_MySpriteObject, "
+            "getVariableForObject(MySpriteObject, myVariable), "
+            "getVariableForObject(MySpriteObject, myOtherVariable))");
+      }
+      SECTION("Object variable with object function call") {
+        auto node = parser.ParseExpression(
+            "MySpriteObject.GetObjectVariableAsNumber(myVariable)");
+        gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                            "",
+                                                            codeGenerator,
+                                                            context);
+
+        REQUIRE(node);
+        node->Visit(expressionCodeGenerator);
+        REQUIRE(
+            expressionCodeGenerator.GetOutput() ==
+            "MySpriteObject.returnVariable(getVariableForObject("
+            "MySpriteObject, myVariable)) ?? 0");
+      }
     }
     SECTION("Child access") {
-      {
+      SECTION("1 child") {
+        auto node = parser.ParseExpression(
+            "MyExtension::GetVariableAsNumber(myVariable.child1)");
+        gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                            "",
+                                                            codeGenerator,
+                                                            context);
+
+        REQUIRE(node);
+        node->Visit(expressionCodeGenerator);
+        REQUIRE(expressionCodeGenerator.GetOutput() ==
+                "returnVariable(getLayoutVariable(myVariable).getChild("
+                "\"child1\"))");
+      }
+      SECTION("2 children") {
         auto node = parser.ParseExpression(
-            "number",
             "MyExtension::GetVariableAsNumber(myVariable.child1.child2)");
-        gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+        gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                            "",
+                                                            codeGenerator,
                                                             context);
 
         REQUIRE(node);
@@ -415,12 +566,13 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
                 "returnVariable(getLayoutVariable(myVariable).getChild("
                 "\"child1\").getChild(\"child2\"))");
       }
-      {
+      SECTION("bracket access") {
         auto node = parser.ParseExpression(
-            "number",
             "MyExtension::GetVariableAsNumber(myVariable[ \"hello\" + "
             "\"world\" ].child2)");
-        gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+        gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                            "",
+                                                            codeGenerator,
                                                             context);
 
         REQUIRE(node);
@@ -429,13 +581,14 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
                 "returnVariable(getLayoutVariable(myVariable).getChild("
                 "\"hello\" + \"world\").getChild(\"child2\"))");
       }
-      {
+      SECTION("bracket access with nested variable") {
         auto node = parser.ParseExpression(
-            "number",
             "MyExtension::GetVariableAsNumber(myVariable[ \"hello\" + "
             "MySpriteObject.GetObjectStringWith1Param(MyOtherSpriteObject."
             "GetObjectVariableAsNumber(mySecondVariable)) ].child2)");
-        gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+        gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                            "",
+                                                            codeGenerator,
                                                             context);
 
         REQUIRE(node);
@@ -462,8 +615,10 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
   }
   SECTION("Mixed test (1)") {
     {
-      auto node = parser.ParseExpression("number", "-+-MyExtension::MouseX(,)");
-      gd::ExpressionCodeGenerator expressionCodeGenerator(codeGenerator,
+      auto node = parser.ParseExpression("-+-MyExtension::MouseX(,)");
+      gd::ExpressionCodeGenerator expressionCodeGenerator("number",
+                                                          "",
+                                                          codeGenerator,
                                                           context);
 
       REQUIRE(node);

Core/tests/ExpressionCompletionFinder.cpp

@@ -19,16 +19,17 @@ TEST_CASE("ExpressionCompletionFinder", "[common][events]") {
   gd::Platform platform;
   SetupProjectWithDummyPlatform(project, platform);
   auto& layout1 = project.InsertNewLayout("Layout1", 0);
+  layout1.InsertNewObject(project, "MyExtension::Sprite", "MyObject", 0);
 
-  gd::ExpressionParser2 parser(platform, project, layout1);
+  gd::ExpressionParser2 parser;
 
   auto getCompletionsFor = [&](const gd::String& type,
                                const gd::String& expression,
                                size_t location) {
-    auto node = parser.ParseExpression(type, expression);
+    auto node = parser.ParseExpression(expression);
     REQUIRE(node != nullptr);
     return gd::ExpressionCompletionFinder::GetCompletionDescriptionsFor(
-        *node, location);
+        platform, project, layout1, type, *node, location);
   };
 
   const std::vector<gd::ExpressionCompletionDescription>
@@ -66,6 +67,24 @@ TEST_CASE("ExpressionCompletionFinder", "[common][events]") {
       REQUIRE(getCompletionsFor("number|string", "My", 2) ==
               expectedEmptyCompletions);
     }
+    SECTION("Object or expression completions in a variable name") {
+      std::vector<gd::ExpressionCompletionDescription> expectedCompletions{
+          gd::ExpressionCompletionDescription::ForObject("string", "My", 0, 2),
+          gd::ExpressionCompletionDescription::ForExpression(
+              "string", "My", 0, 2)};
+      REQUIRE(getCompletionsFor("number", "MyExtension::GetVariableAsNumber(MyVariable[\"abc\" + My", 52) == expectedCompletions);
+      REQUIRE(getCompletionsFor("number", "MyExtension::GetVariableAsNumber(MyVariable[\"abc\" + My", 53) == expectedCompletions);
+      REQUIRE(getCompletionsFor("number", "MyExtension::GetVariableAsNumber(MyVariable[\"abc\" + My", 54) == expectedEmptyCompletions);
+    }
+    SECTION("Object or expression completions in a variable index") {
+      std::vector<gd::ExpressionCompletionDescription> expectedCompletions{
+          gd::ExpressionCompletionDescription::ForObject("number", "My", 0, 2),
+          gd::ExpressionCompletionDescription::ForExpression(
+              "number", "My", 0, 2)};
+      REQUIRE(getCompletionsFor("number", "MyExtension::GetVariableAsNumber(MyVariable[12345 + My", 52) == expectedCompletions);
+      REQUIRE(getCompletionsFor("number", "MyExtension::GetVariableAsNumber(MyVariable[12345 + My", 53) == expectedCompletions);
+      REQUIRE(getCompletionsFor("number", "MyExtension::GetVariableAsNumber(MyVariable[12345 + My", 54) == expectedEmptyCompletions);
+    }
     SECTION("Object when type is an object") {
       std::vector<gd::ExpressionCompletionDescription> expectedCompletions{
           gd::ExpressionCompletionDescription::ForObject("object", "My", 0, 2)};
@@ -143,6 +162,17 @@ TEST_CASE("ExpressionCompletionFinder", "[common][events]") {
                                 "MyExtension::GetVariableAsNumber(myVar",
                                 33) == expectedCompletions);
     }
+    SECTION("Object function with a Variable as argument") {
+      std::vector<gd::ExpressionCompletionDescription> expectedCompletions{
+          gd::ExpressionCompletionDescription::ForVariable(
+              "objectvar", "myVar", 35, 40, "MyObject")};
+        getCompletionsFor("number",
+                                "MyObject.GetObjectVariableAsNumber(myVar",
+                                35);
+      REQUIRE(getCompletionsFor("number",
+                                "MyObject.GetObjectVariableAsNumber(myVar",
+                                35) == expectedCompletions);
+    }
     SECTION("Function with a Layer as argument") {
       std::vector<gd::ExpressionCompletionDescription> expectedCompletions{
           gd::ExpressionCompletionDescription::ForText(

Core/tests/ExpressionNodeLocationFinder.cpp

@@ -14,10 +14,9 @@
 
 template <class TNode>
 bool CheckNodeAtLocationIs(gd::ExpressionParser2& parser,
-                           const gd::String& type,
                            const gd::String& expression,
                            size_t searchPosition) {
-  auto node = parser.ParseExpression(type, expression);
+  auto node = parser.ParseExpression(expression);
   REQUIRE(node != nullptr);
   return dynamic_cast<TNode*>(
              gd::ExpressionNodeLocationFinder::GetNodeAtPosition(
@@ -26,10 +25,9 @@ bool CheckNodeAtLocationIs(gd::ExpressionParser2& parser,
 
 template <class TNode>
 bool CheckParentNodeAtLocationIs(gd::ExpressionParser2& parser,
-                           const gd::String& type,
                            const gd::String& expression,
                            size_t searchPosition) {
-  auto node = parser.ParseExpression(type, expression);
+  auto node = parser.ParseExpression(expression);
   REQUIRE(node != nullptr);
   return dynamic_cast<TNode*>(
              gd::ExpressionNodeLocationFinder::GetParentNodeAtPosition(
@@ -37,20 +35,18 @@ bool CheckParentNodeAtLocationIs(gd::ExpressionParser2& parser,
 }
 
 bool CheckNoNodeAtLocation(gd::ExpressionParser2& parser,
-                           const gd::String& type,
                            const gd::String& expression,
                            size_t searchPosition) {
-  auto node = parser.ParseExpression(type, expression);
+  auto node = parser.ParseExpression(expression);
   REQUIRE(node != nullptr);
   return gd::ExpressionNodeLocationFinder::GetNodeAtPosition(
              *node, searchPosition) == nullptr;
 }
 
 bool CheckNoParentNodeAtLocation(gd::ExpressionParser2& parser,
-                           const gd::String& type,
                            const gd::String& expression,
                            size_t searchPosition) {
-  auto node = parser.ParseExpression(type, expression);
+  auto node = parser.ParseExpression(expression);
   REQUIRE(node != nullptr);
   return gd::ExpressionNodeLocationFinder::GetParentNodeAtPosition(
              *node, searchPosition) == nullptr;
@@ -63,21 +59,21 @@ TEST_CASE("ExpressionNodeLocationFinder", "[common][events]") {
   auto& layout1 = project.InsertNewLayout("Layout1", 0);
   layout1.InsertNewObject(project, "MyExtension::Sprite", "MySpriteObject", 0);
 
-  gd::ExpressionParser2 parser(platform, project, layout1);
+  gd::ExpressionParser2 parser;
 
   SECTION("Empty expressions") {
     SECTION("Test 1") {
       REQUIRE(CheckNodeAtLocationIs<gd::EmptyNode>(
-                  parser, "string", "", 0) == true);
-      REQUIRE(CheckNoNodeAtLocation(parser, "string", "", 1) ==
+                  parser, "", 0) == true);
+      REQUIRE(CheckNoNodeAtLocation(parser, "", 1) ==
               true);
     }
     SECTION("Test 2") {
-      REQUIRE(CheckNoNodeAtLocation(parser, "string", " ", 0) ==
+      REQUIRE(CheckNoNodeAtLocation(parser, " ", 0) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::EmptyNode>(
-                  parser, "string", " ", 1) == true);
-      REQUIRE(CheckNoNodeAtLocation(parser, "string", " ", 2) ==
+                  parser, " ", 1) == true);
+      REQUIRE(CheckNoNodeAtLocation(parser, " ", 2) ==
               true);
     }
   }
@@ -85,270 +81,255 @@ TEST_CASE("ExpressionNodeLocationFinder", "[common][events]") {
   SECTION("Valid text") {
     SECTION("Test 1") {
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                  parser, "string", "\"Hello world\"", 0) == true);
+                  parser, "\"Hello world\"", 0) == true);
     }
     SECTION("Test 2") {
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                  parser, "string", "\"Hello world\"", 1) == true);
+                  parser, "\"Hello world\"", 1) == true);
     }
     SECTION("Test 3") {
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                  parser, "string", "\"Hello world\"", 12) == true);
+                  parser, "\"Hello world\"", 12) == true);
     }
     SECTION("Test 4") {
-      REQUIRE(CheckNoNodeAtLocation(parser, "string", "\"Hello world\"", 13) ==
+      REQUIRE(CheckNoNodeAtLocation(parser, "\"Hello world\"", 13) ==
               true);
     }
     SECTION("Test 5") {
-      REQUIRE(CheckNoNodeAtLocation(parser, "string", "\"Hello world\"", 99) ==
+      REQUIRE(CheckNoNodeAtLocation(parser, "\"Hello world\"", 99) ==
               true);
     }
   }
   SECTION("Valid text operators") {
     SECTION("Test 1") {
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                  parser, "string", "\"Hello \" + \"World\"", 1) == true);
+                  parser, "\"Hello \" + \"World\"", 1) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "string", "\"Hello \" + \"World\"", 8) == true);
+                  parser, "\"Hello \" + \"World\"", 8) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                  parser, "string", "\"Hello \" + \"World\"", 15) == true);
+                  parser, "\"Hello \" + \"World\"", 15) == true);
     }
   }
   SECTION("Invalid texts") {
-    REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(parser, "string", "\"", 0) ==
+    REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(parser, "\"", 0) ==
             true);
-    REQUIRE(CheckNoNodeAtLocation(parser, "string", "\"", 1) == true);
-    REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(parser, "string", "\"a", 1) ==
+    REQUIRE(CheckNoNodeAtLocation(parser, "\"", 1) == true);
+    REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(parser, "\"a", 1) ==
             true);
   }
 
   SECTION("Invalid parenthesis") {
     REQUIRE(CheckNodeAtLocationIs<gd::SubExpressionNode>(
-                parser, "string", "((\"hello\"", 1) == true);
+                parser, "((\"hello\"", 1) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                parser, "string", "((\"hello\"", 2) == true);
+                parser, "((\"hello\"", 2) == true);
   }
 
   SECTION("Invalid text operators") {
     SECTION("Test 1") {
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                  parser, "string", "\"Hello \" - \"World\"", 0) == true);
+                  parser, "\"Hello \" - \"World\"", 0) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                  parser, "string", "\"Hello \" - \"World\"", 1) == true);
+                  parser, "\"Hello \" - \"World\"", 1) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "string", "\"Hello \" / \"World\"", 8) == true);
+                  parser, "\"Hello \" / \"World\"", 8) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
-                  parser, "string", "\"Hello \" * \"World\"", 15) == true);
+                  parser, "\"Hello \" * \"World\"", 15) == true);
     }
   }
 
   SECTION("Valid unary operators") {
     SECTION("Test 1") {
       REQUIRE(CheckNodeAtLocationIs<gd::UnaryOperatorNode>(
-                  parser, "number", "-123", 0) == true);
+                  parser, "-123", 0) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::UnaryOperatorNode>(
-                  parser, "number", "+123", 0) == true);
+                  parser, "+123", 0) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "-123", 1) == true);
+                  parser, "-123", 1) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "-123", 2) == true);
+                  parser, "-123", 2) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "-123", 3) == true);
-      REQUIRE(CheckNoNodeAtLocation(parser, "number", "-123", 4) == true);
+                  parser, "-123", 3) == true);
+      REQUIRE(CheckNoNodeAtLocation(parser, "-123", 4) == true);
     }
     SECTION("Test 2") {
       REQUIRE(CheckNodeAtLocationIs<gd::UnaryOperatorNode>(
-                  parser, "number", "-+-123", 0) == true);
+                  parser, "-+-123", 0) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::UnaryOperatorNode>(
-                  parser, "number", "-+-123", 1) == true);
+                  parser, "-+-123", 1) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::UnaryOperatorNode>(
-                  parser, "number", "-+-123", 2) == true);
+                  parser, "-+-123", 2) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "-+-123", 3) == true);
+                  parser, "-+-123", 3) == true);
     }
   }
 
   SECTION("Invalid number operators") {
     SECTION("Test 1") {
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "12 ! 34", 0) == true);
+                  parser, "12 ! 34", 0) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "12 ! 34", 1) == true);
+                  parser, "12 ! 34", 1) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "12 ! 34", 2) == true);
+                  parser, "12 ! 34", 2) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "12 ! 34", 3) == true);
+                  parser, "12 ! 34", 3) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "12 ! 34", 4) == true);
+                  parser, "12 ! 34", 4) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "12 ! 34", 5) == true);
+                  parser, "12 ! 34", 5) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "12 ! 34", 6) == true);
+                  parser, "12 ! 34", 6) == true);
     }
     SECTION("Test 2") {
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "1 / /2", 0) == true);
+                  parser, "1 / /2", 0) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "1 / /2", 1) == true);
+                  parser, "1 / /2", 1) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "1 / /2", 2) == true);
+                  parser, "1 / /2", 2) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "1 / /2", 3) == true);
+                  parser, "1 / /2", 3) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::EmptyNode>(
-                  parser, "number", "1 / /2", 4) == true);
+                  parser, "1 / /2", 4) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::EmptyNode>(
-                  parser, "number", "1 / /2", 5) == true);
+                  parser, "1 / /2", 5) == true);
     }
   }
 
   SECTION("Numbers and texts mismatchs") {
-    REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(parser, "number", "12+\"hello\"", 0) == true);
-    REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(parser, "number", "12+\"hello\"", 1) == true);
-    REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(parser, "number", "12+\"hello\"", 2) == true);
-    REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(parser, "number", "12+\"hello\"", 3) == true);
+    REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(parser, "12+\"hello\"", 0) == true);
+    REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(parser, "12+\"hello\"", 1) == true);
+    REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(parser, "12+\"hello\"", 2) == true);
+    REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(parser, "12+\"hello\"", 3) == true);
   }
 
   SECTION("Numbers and texts mismatchs (parent node)") {
-    REQUIRE(CheckParentNodeAtLocationIs<gd::OperatorNode>(parser, "number", "12+\"hello\"", 0) == true);
-    REQUIRE(CheckParentNodeAtLocationIs<gd::OperatorNode>(parser, "number", "12+\"hello\"", 1) == true);
-    REQUIRE(CheckNoParentNodeAtLocation(parser, "number", "12+\"hello\"", 2) == true);
-    REQUIRE(CheckParentNodeAtLocationIs<gd::OperatorNode>(parser, "number", "12+\"hello\"", 3) == true);
+    REQUIRE(CheckParentNodeAtLocationIs<gd::OperatorNode>(parser, "12+\"hello\"", 0) == true);
+    REQUIRE(CheckParentNodeAtLocationIs<gd::OperatorNode>(parser, "12+\"hello\"", 1) == true);
+    REQUIRE(CheckNoParentNodeAtLocation(parser, "12+\"hello\"", 2) == true);
+    REQUIRE(CheckParentNodeAtLocationIs<gd::OperatorNode>(parser, "12+\"hello\"", 3) == true);
   }
 
   SECTION("Valid objects") {
     REQUIRE(CheckNodeAtLocationIs<gd::IdentifierNode>(
-                parser, "object", "HelloWorld1", 0) == true);
+                parser, "HelloWorld1", 0) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::IdentifierNode>(
-                parser, "object", "HelloWorld1", 1) == true);
+                parser, "HelloWorld1", 1) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::IdentifierNode>(
-                parser, "object", "HelloWorld1", 10) == true);
-    REQUIRE(CheckNoNodeAtLocation(parser, "object", "HelloWorld1", 11) == true);
+                parser, "HelloWorld1", 10) == true);
+    REQUIRE(CheckNoNodeAtLocation(parser, "HelloWorld1", 11) == true);
   }
   SECTION("Valid objects (parent node)") {
     REQUIRE(CheckNoParentNodeAtLocation(
-                parser, "object", "HelloWorld1", 0) == true);
+                parser, "HelloWorld1", 0) == true);
   }
   SECTION("Invalid objects") {
     REQUIRE(CheckNodeAtLocationIs<gd::IdentifierNode>(
-                parser, "object", "a+b", 0) == true);
+                parser, "a+b", 0) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                parser, "object", "a+b", 1) == true);
+                parser, "a+b", 1) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::IdentifierNode>(
-                parser, "object", "a+b", 2) == true);
-    REQUIRE(CheckNoNodeAtLocation(parser, "object", "a+b", 3) == true);
+                parser, "a+b", 2) == true);
+    REQUIRE(CheckNoNodeAtLocation(parser, "a+b", 3) == true);
   }
   SECTION("Valid function calls") {
     SECTION("Test 1") {
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 0) ==
+                  parser, "12 + MyExtension::GetNumber()", 0) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 1) ==
+                  parser, "12 + MyExtension::GetNumber()", 1) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 2) ==
+                  parser, "12 + MyExtension::GetNumber()", 2) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 3) ==
+                  parser, "12 + MyExtension::GetNumber()", 3) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 4) ==
+                  parser, "12 + MyExtension::GetNumber()", 4) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 5) ==
+                  parser, "12 + MyExtension::GetNumber()", 5) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 27) ==
+                  parser, "12 + MyExtension::GetNumber()", 27) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 28) ==
+                  parser, "12 + MyExtension::GetNumber()", 28) ==
               true);
       REQUIRE(CheckNoNodeAtLocation(
-                  parser, "number", "12 + MyExtension::GetNumber()", 29) ==
+                  parser, "12 + MyExtension::GetNumber()", 29) ==
               true);
     }
     SECTION("Test 2") {
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   0) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   1) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   33) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   34) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   35) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   36) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   37) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   38) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   39) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::TextNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   50) == true);
       REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   51) == true);
       REQUIRE(CheckNoNodeAtLocation(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   52) == true);
     }
     SECTION("Parent node") {
       REQUIRE(CheckParentNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 0) ==
+                  parser, "12 + MyExtension::GetNumber()", 0) ==
               true);
       REQUIRE(CheckParentNodeAtLocationIs<gd::OperatorNode>(
-                  parser, "number", "12 + MyExtension::GetNumber()", 6) ==
+                  parser, "12 + MyExtension::GetNumber()", 6) ==
               true);
       REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   35) == true);
       REQUIRE(CheckParentNodeAtLocationIs<gd::FunctionCallNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   35) == true);
       REQUIRE(CheckParentNodeAtLocationIs<gd::FunctionCallNode>(
                   parser,
-                  "number",
                   "MyExtension::GetNumberWith2Params(12, \"hello world\")",
                   39) == true);
     }
@@ -356,66 +337,67 @@ TEST_CASE("ExpressionNodeLocationFinder", "[common][events]") {
 
   SECTION("Invalid function calls") {
     REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(12)", 0) == true);
+                parser, "Idontexist(12)", 0) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(12)", 1) == true);
+                parser, "Idontexist(12)", 1) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(12)", 2) == true);
+                parser, "Idontexist(12)", 2) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(12)", 10) == true);
+                parser, "Idontexist(12)", 10) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                parser, "number", "Idontexist(12)", 11) == true);
+                parser, "Idontexist(12)", 11) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                parser, "number", "Idontexist(12)", 12) == true);
+                parser, "Idontexist(12)", 12) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(12)", 13) == true);
-    REQUIRE(CheckNoNodeAtLocation(parser, "number", "Idontexist(12)", 14) ==
+                parser, "Idontexist(12)", 13) == true);
+    REQUIRE(CheckNoNodeAtLocation(parser, "Idontexist(12)", 14) ==
             true);
   }
   SECTION("Invalid function calls (parent node)") {
     REQUIRE(CheckNodeAtLocationIs<gd::NumberNode>(
-                parser, "number", "Idontexist(12)", 12) == true);
+                parser, "Idontexist(12)", 12) == true);
     REQUIRE(CheckParentNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(12)", 12) == true);
+                parser, "Idontexist(12)", 12) == true);
   }
 
   SECTION("Unterminated function calls") {
     REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(", 0) == true);
+                parser, "Idontexist(", 0) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(", 1) == true);
+                parser, "Idontexist(", 1) == true);
     REQUIRE(CheckNodeAtLocationIs<gd::FunctionCallNode>(
-                parser, "number", "Idontexist(", 10) == true);
-    REQUIRE(CheckNoNodeAtLocation(parser, "number", "Idontexist(", 11) == true);
+                parser, "Idontexist(", 10) == true);
+    REQUIRE(CheckNoNodeAtLocation(parser, "Idontexist(", 11) == true);
   }
 
   SECTION("Valid variables") {
     SECTION("Test 1") {
-      REQUIRE(CheckNodeAtLocationIs<gd::VariableNode>(
-                  parser, "scenevar", "myVariable", 0) == true);
-      REQUIRE(CheckNodeAtLocationIs<gd::VariableNode>(
-                  parser, "scenevar", "myVariable", 9) == true);
-      REQUIRE(CheckNoNodeAtLocation(parser, "scenevar", "myVariable", 10) ==
+      REQUIRE(CheckNodeAtLocationIs<gd::IdentifierNode>(
+                  parser, "myVariable", 0) == true);
+      REQUIRE(CheckNodeAtLocationIs<gd::IdentifierNode>(
+                  parser, "myVariable", 9) == true);
+      REQUIRE(CheckNoNodeAtLocation(parser, "myVariable", 10) ==
               true);
     }
     SECTION("Test 2") {
-      auto node = parser.ParseExpression("scenevar", "Var1.Child1");
+      auto node = parser.ParseExpression("Var1.Child1");
       REQUIRE(node != nullptr);
 
       auto var1Node =
           gd::ExpressionNodeLocationFinder::GetNodeAtPosition(*node, 0);
-      REQUIRE(dynamic_cast<gd::VariableNode*>(var1Node) != nullptr);
-      REQUIRE(dynamic_cast<gd::VariableNode&>(*var1Node).name == "Var1");
+      REQUIRE(dynamic_cast<gd::IdentifierNode*>(var1Node) != nullptr);
+      REQUIRE(dynamic_cast<gd::IdentifierNode&>(*var1Node).identifierName == "Var1");
 
+      // It's actually the same node.
       auto child1Node =
           gd::ExpressionNodeLocationFinder::GetNodeAtPosition(*node, 4);
-      REQUIRE(dynamic_cast<gd::VariableAccessorNode*>(child1Node) != nullptr);
-      REQUIRE(dynamic_cast<gd::VariableAccessorNode&>(*child1Node).name ==
+      REQUIRE(dynamic_cast<gd::IdentifierNode*>(child1Node) != nullptr);
+      REQUIRE(dynamic_cast<gd::IdentifierNode&>(*child1Node).childIdentifierName ==
               "Child1");
     }
     SECTION("Test 3") {
       auto node = parser.ParseExpression(
-          "scenevar", "myVariable[ \"My named children\"  ].grandChild");
+          "myVariable[ \"My named children\"  ].grandChild");
       REQUIRE(node != nullptr);
 
       auto myVariableNode =

Core/tests/ExpressionParser2Benchmarks.cpp

@@ -21,13 +21,15 @@ TEST_CASE("ExpressionParser2 - Benchmarks", "[common][events]") {
   auto &layout1 = project.InsertNewLayout("Layout1", 0);
   layout1.InsertNewObject(project, "MyExtension::Sprite", "MySpriteObject", 0);
 
-  gd::ExpressionParser2 parser(platform, project, layout1);
+  gd::ExpressionParser2 parser;
 
-  auto parseExpression = [&parser](const gd::String &expression) {
-    auto parseExpressionWithType = [&parser,
+  auto parseExpression = [&parser, &project, &platform, &layout1](const gd::String &expression) {
+    auto parseExpressionWithType = [&parser, &project, &platform, &layout1,
                                     &expression](const gd::String &type) {
-      auto node = parser.ParseExpression(type, expression);
+      auto node = parser.ParseExpression(expression);
       REQUIRE(node != nullptr);
+      gd::ExpressionValidator validator(platform, project, layout1, type);
+      node->Visit(validator);
     };
 
     parseExpressionWithType("number");

Core/tests/ExpressionParser2NaugtyStrings.cpp

@@ -21,7 +21,7 @@ TEST_CASE("ExpressionParser2 - Naughty strings", "[common][events]") {
   auto &layout1 = project.InsertNewLayout("Layout1", 0);
   layout1.InsertNewObject(project, "MyExtension::Sprite", "MySpriteObject", 0);
 
-  gd::ExpressionParser2 parser(platform, project, layout1);
+  gd::ExpressionParser2 parser;
 
   SECTION("Check that no naughty string crash the parser") {
     std::string inputFile = std::string(__FILE__) + "-blns.txt";
@@ -31,9 +31,9 @@ TEST_CASE("ExpressionParser2 - Naughty strings", "[common][events]") {
       std::string line;
       size_t count = 0;
       while ( std::getline (myfile,line) ) {
-        auto node1 = parser.ParseExpression("string", line.c_str());
+        auto node1 = parser.ParseExpression(line.c_str());
         REQUIRE(node1 != nullptr);
-        auto node2 = parser.ParseExpression("number", line.c_str());
+        auto node2 = parser.ParseExpression(line.c_str());
         REQUIRE(node2 != nullptr);
 
         count++;

Core/tests/ExpressionParser2NodePrinter.cpp

@@ -20,12 +20,12 @@ TEST_CASE("ExpressionParser2NodePrinter", "[common][events]") {
   auto &layout1 = project.InsertNewLayout("Layout1", 0);
   layout1.InsertNewObject(project, "MyExtension::Sprite", "MySpriteObject", 0);
 
-  gd::ExpressionParser2 parser(platform, project, layout1);
+  gd::ExpressionParser2 parser;
 
   auto testPrinter = [&parser](const gd::String &type,
                                const gd::String &expression,
                                const gd::String &expectedOutput = "") {
-    auto node = parser.ParseExpression(type, expression);
+    auto node = parser.ParseExpression(expression);
     REQUIRE(node != nullptr);
     gd::ExpressionParser2NodePrinter printer;
     node->Visit(printer);

GDJS/GDJS/Events/CodeGeneration/EventsCodeGenerator.cpp

@@ -33,7 +33,6 @@ using namespace std;
 namespace gdjs {
 
 gd::String EventsCodeGenerator::GenerateEventsListCompleteFunctionCode(
-    gd::Project& project,
     gdjs::EventsCodeGenerator& codeGenerator,
     gd::String fullyQualifiedFunctionName,
     gd::String functionArgumentsCode,
@@ -89,7 +88,7 @@ gd::String EventsCodeGenerator::GenerateEventsListCompleteFunctionCode(
 }
 
 gd::String EventsCodeGenerator::GenerateLayoutCode(
-    gd::Project& project,
+    const gd::Project& project,
     const gd::Layout& scene,
     const gd::String& codeNamespace,
     std::set<gd::String>& includeFiles,
@@ -99,7 +98,6 @@ gd::String EventsCodeGenerator::GenerateLayoutCode(
   codeGenerator.SetGenerateCodeForRuntime(compilationForRuntime);
 
   gd::String output = GenerateEventsListCompleteFunctionCode(
-      project,
       codeGenerator,
       codeGenerator.GetCodeNamespaceAccessor() + "func",
       "runtimeScene",
@@ -128,7 +126,6 @@ gd::String EventsCodeGenerator::GenerateEventsFunctionCode(
   codeGenerator.SetGenerateCodeForRuntime(compilationForRuntime);
 
   gd::String output = GenerateEventsListCompleteFunctionCode(
-      project,
       codeGenerator,
       codeGenerator.GetCodeNamespaceAccessor() + "func",
       codeGenerator.GenerateEventsFunctionParameterDeclarationsList(
@@ -191,7 +188,6 @@ gd::String EventsCodeGenerator::GenerateBehaviorEventsFunctionCode(
           "Behavior");
 
   gd::String output = GenerateEventsListCompleteFunctionCode(
-      project,
       codeGenerator,
       fullyQualifiedFunctionName,
       codeGenerator.GenerateEventsFunctionParameterDeclarationsList(
@@ -981,7 +977,7 @@ gd::String EventsCodeGenerator::GenerateConditionsListCode(
 }
 
 gd::String EventsCodeGenerator::GenerateParameterCodes(
-    const gd::String& parameter,
+    const gd::Expression& parameter,
     const gd::ParameterMetadata& metadata,
     gd::EventsCodeGenerationContext& context,
     const gd::String& lastObjectName,
@@ -1224,7 +1220,7 @@ gd::String EventsCodeGenerator::GenerateProfilerSectionEnd(
          ConvertToStringExplicit(section) + "); }";
 }
 
-EventsCodeGenerator::EventsCodeGenerator(gd::Project& project,
+EventsCodeGenerator::EventsCodeGenerator(const gd::Project& project,
                                          const gd::Layout& layout)
     : gd::EventsCodeGenerator(project, layout, JsPlatform::Get()) {}
 

GDJS/GDJS/Events/CodeGeneration/EventsCodeGenerator.h

@@ -44,7 +44,7 @@ class EventsCodeGenerator : public gd::EventsCodeGenerator {
    *
    * \return JavaScript code
    */
-  static gd::String GenerateLayoutCode(gd::Project& project,
+  static gd::String GenerateLayoutCode(const gd::Project& project,
                                        const gd::Layout& scene,
                                        const gd::String& codeNamespace,
                                        std::set<gd::String>& includeFiles,
@@ -174,7 +174,7 @@ class EventsCodeGenerator : public gd::EventsCodeGenerator {
 
  protected:
   virtual gd::String GenerateParameterCodes(
-      const gd::String& parameter,
+      const gd::Expression& parameter,
       const gd::ParameterMetadata& metadata,
       gd::EventsCodeGenerationContext& context,
       const gd::String& lastObjectName,
@@ -289,7 +289,6 @@ class EventsCodeGenerator : public gd::EventsCodeGenerator {
 
  private:
   static gd::String GenerateEventsListCompleteFunctionCode(
-      gd::Project& project,
       gdjs::EventsCodeGenerator& codeGenerator,
       gd::String fullyQualifiedFunctionName,
       gd::String functionArgumentsCode,
@@ -352,7 +351,7 @@ class EventsCodeGenerator : public gd::EventsCodeGenerator {
   /**
    * \brief Construct a code generator for the specified project and layout.
    */
-  EventsCodeGenerator(gd::Project& project, const gd::Layout& layout);
+  EventsCodeGenerator(const gd::Project& project, const gd::Layout& layout);
 
   /**
    * \brief Construct a code generator for the specified objects and groups.

GDJS/GDJS/Events/CodeGeneration/LayoutCodeGenerator.h

@@ -22,7 +22,7 @@ namespace gdjs {
  */
 class LayoutCodeGenerator {
  public:
-  LayoutCodeGenerator(gd::Project& project_)
+  LayoutCodeGenerator(const gd::Project& project_)
       : project(project_){};
 
   /**
@@ -34,7 +34,7 @@ class LayoutCodeGenerator {
       bool compilationForRuntime);
 
  private:
-  gd::Project& project;
+  const gd::Project& project;
 };
 
 }  // namespace gdjs

GDJS/GDJS/Extensions/Builtin/BaseObjectExtension.cpp

@@ -367,14 +367,16 @@ BaseObjectExtension::BaseObjectExtension() {
                   codeGenerator,
                   context,
                   "number",
-                  instruction.GetParameter(2).GetPlainString());
+                  instruction.GetParameter(2).GetPlainString(),
+                  instruction.GetParameter(0).GetPlainString());
 
           gd::String expression2Code =
               gd::ExpressionCodeGenerator::GenerateExpressionCode(
                   codeGenerator,
                   context,
                   "number",
-                  instruction.GetParameter(4).GetPlainString());
+                  instruction.GetParameter(4).GetPlainString(),
+                  instruction.GetParameter(0).GetPlainString());
 
           gd::String op1 = instruction.GetParameter(1).GetPlainString();
           gd::String newX =
@@ -422,14 +424,16 @@ BaseObjectExtension::BaseObjectExtension() {
                   codeGenerator,
                   context,
                   "number",
-                  instruction.GetParameter(2).GetPlainString());
+                  instruction.GetParameter(2).GetPlainString(),
+                  instruction.GetParameter(0).GetPlainString());
 
           gd::String expression2Code =
               gd::ExpressionCodeGenerator::GenerateExpressionCode(
                   codeGenerator,
                   context,
                   "number",
-                  instruction.GetParameter(4).GetPlainString());
+                  instruction.GetParameter(4).GetPlainString(),
+                  instruction.GetParameter(0).GetPlainString());
 
           gd::String op1 = instruction.GetParameter(1).GetPlainString();
           gd::String newX = isNotAssignmentOperator(op1)

GDJS/GDJS/IDE/ExporterHelper.cpp

@@ -77,6 +77,43 @@ bool ExporterHelper::ExportProjectForPixiPreview(
   fs.ClearDir(options.exportPath);
   std::vector<gd::String> includesFiles;
 
+  const gd::Project &immutableProject = options.project;
+
+  // Export engine libraries
+  AddLibsInclude(/*pixiRenderers=*/true,
+                 /*includeWebsocketDebuggerClient=*/
+                 !options.websocketDebuggerServerAddress.empty(),
+                 /*includeWindowMessageDebuggerClient=*/
+                 options.useWindowMessageDebuggerClient,
+                 immutableProject.GetLoadingScreen().GetGDevelopLogoStyle(),
+                 includesFiles);
+
+  // Export files for object and behaviors
+  ExportObjectAndBehaviorsIncludes(immutableProject, includesFiles);
+
+  // Export effects (after engine libraries as they auto-register themselves to
+  // the engine)
+  ExportEffectIncludes(immutableProject, includesFiles);
+
+  previousTime = LogTimeSpent("Include files export", previousTime);
+
+  if (!options.projectDataOnlyExport) {
+    // Generate events code
+    if (!ExportEventsCode(immutableProject, codeOutputDir, includesFiles, true))
+      return false;
+
+    // Export source files
+    if (!ExportExternalSourceFiles(
+            immutableProject, codeOutputDir, includesFiles)) {
+      gd::LogError(
+          _("Error during exporting! Unable to export source files:\n") +
+          lastError);
+      return false;
+    }
+
+    previousTime = LogTimeSpent("Events code export", previousTime);
+  }
+
   gd::Project exportedProject = options.project;
 
   if (!options.fullLoadingScreen) {
@@ -99,41 +136,6 @@ bool ExporterHelper::ExportProjectForPixiPreview(
       fs, exportedProject.GetResourcesManager(), options.exportPath);
   // end of compatibility code
 
-  // Export engine libraries
-  AddLibsInclude(/*pixiRenderers=*/true,
-                 /*includeWebsocketDebuggerClient=*/
-                 !options.websocketDebuggerServerAddress.empty(),
-                 /*includeWindowMessageDebuggerClient=*/
-                 options.useWindowMessageDebuggerClient,
-                 exportedProject.GetLoadingScreen().GetGDevelopLogoStyle(),
-                 includesFiles);
-
-  // Export files for object and behaviors
-  ExportObjectAndBehaviorsIncludes(exportedProject, includesFiles);
-
-  // Export effects (after engine libraries as they auto-register themselves to
-  // the engine)
-  ExportEffectIncludes(exportedProject, includesFiles);
-
-  previousTime = LogTimeSpent("Include files export", previousTime);
-
-  if (!options.projectDataOnlyExport) {
-    // Generate events code
-    if (!ExportEventsCode(exportedProject, codeOutputDir, includesFiles, true))
-      return false;
-
-    // Export source files
-    if (!ExportExternalSourceFiles(
-            exportedProject, codeOutputDir, includesFiles)) {
-      gd::LogError(
-          _("Error during exporting! Unable to export source files:\n") +
-          lastError);
-      return false;
-    }
-
-    previousTime = LogTimeSpent("Events code export", previousTime);
-  }
-
   // Strip the project (*after* generating events as the events may use stripped
   // things (objects groups...))
   gd::ProjectStripper::StripProjectForExport(exportedProject);
@@ -623,7 +625,7 @@ void ExporterHelper::RemoveIncludes(bool pixiRenderers,
 }
 
 bool ExporterHelper::ExportEffectIncludes(
-    gd::Project &project, std::vector<gd::String> &includesFiles) {
+    const gd::Project &project, std::vector<gd::String> &includesFiles) {
   std::set<gd::String> effectIncludes;
 
   gd::EffectsCodeGenerator::GenerateEffectsIncludeFiles(
@@ -634,7 +636,7 @@ bool ExporterHelper::ExportEffectIncludes(
   return true;
 }
 
-bool ExporterHelper::ExportEventsCode(gd::Project &project,
+bool ExporterHelper::ExportEventsCode(const gd::Project &project,
                                       gd::String outputDir,
                                       std::vector<gd::String> &includesFiles,
                                       bool exportForPreview) {
@@ -642,7 +644,7 @@ bool ExporterHelper::ExportEventsCode(gd::Project &project,
 
   for (std::size_t i = 0; i < project.GetLayoutsCount(); ++i) {
     std::set<gd::String> eventsIncludes;
-    gd::Layout &layout = project.GetLayout(i);
+    const gd::Layout &layout = project.GetLayout(i);
     LayoutCodeGenerator layoutCodeGenerator(project);
     gd::String eventsOutput = layoutCodeGenerator.GenerateLayoutCompleteCode(
         layout, eventsIncludes, !exportForPreview);
@@ -664,7 +666,7 @@ bool ExporterHelper::ExportEventsCode(gd::Project &project,
 }
 
 bool ExporterHelper::ExportExternalSourceFiles(
-    gd::Project &project,
+    const gd::Project &project,
     gd::String outputDir,
     std::vector<gd::String> &includesFiles) {
   const auto &allFiles = project.GetAllSourceFiles();
@@ -765,7 +767,7 @@ bool ExporterHelper::ExportIncludesAndLibs(
 }
 
 void ExporterHelper::ExportObjectAndBehaviorsIncludes(
-    gd::Project &project, std::vector<gd::String> &includesFiles) {
+    const gd::Project &project, std::vector<gd::String> &includesFiles) {
   auto addIncludeFiles = [&](const std::vector<gd::String> &newIncludeFiles) {
     for (const auto &includeFile : newIncludeFiles) {
       InsertUnique(includesFiles, includeFile);
@@ -798,7 +800,7 @@ void ExporterHelper::ExportObjectAndBehaviorsIncludes(
 
   addObjectsIncludeFiles(project);
   for (std::size_t i = 0; i < project.GetLayoutsCount(); ++i) {
-    gd::Layout &layout = project.GetLayout(i);
+    const gd::Layout &layout = project.GetLayout(i);
     addObjectsIncludeFiles(layout);
   }
 }

GDJS/GDJS/IDE/ExporterHelper.h

@@ -224,7 +224,7 @@ class ExporterHelper {
    * includesFiles A reference to a vector that will be filled with JS files to
    * be exported along with the project. ( including "codeX.js" files ).
    */
-  bool ExportEventsCode(gd::Project &project,
+  bool ExportEventsCode(const gd::Project &project,
                         gd::String outputDir,
                         std::vector<gd::String> &includesFiles,
                         bool exportForPreview);
@@ -232,14 +232,14 @@ class ExporterHelper {
   /**
    * \brief Add the project effects include files.
    */
-  bool ExportEffectIncludes(gd::Project &project,
+  bool ExportEffectIncludes(const gd::Project &project,
                             std::vector<gd::String> &includesFiles);
 
   /**
    * \brief Add the include files for all the objects of the project
    * and their behaviors.
    */
-  void ExportObjectAndBehaviorsIncludes(gd::Project &project,
+  void ExportObjectAndBehaviorsIncludes(const gd::Project &project,
                                         std::vector<gd::String> &includesFiles);
 
   /**
@@ -253,7 +253,7 @@ class ExporterHelper {
    * with JS files to be exported along with the project. (including
    * "ext-codeX.js" files).
    */
-  bool ExportExternalSourceFiles(gd::Project &project,
+  bool ExportExternalSourceFiles(const gd::Project &project,
                                  gd::String outputDir,
                                  std::vector<gd::String> &includesFiles);
 

GDevelop.js/Bindings/Bindings.idl

@@ -1074,12 +1074,17 @@ interface Instruction {
     void SetInverted(boolean inverted);
     boolean IsInverted();
     void SetParameter(unsigned long id, [Const] DOMString value);
-    [Const, Ref] DOMString GetParameter(unsigned long id);
+    [Const, Ref] Expression GetParameter(unsigned long id);
     void SetParametersCount(unsigned long count);
     unsigned long GetParametersCount();
     [Ref] InstructionsList GetSubInstructions();
 };
 
+interface Expression {
+  [Const, Ref] DOMString GetPlainString();
+  ExpressionNode GetRootNode();
+};
+
 interface VectorPairStringTextFormatting {
     unsigned long size();
     [Const, Ref] DOMString WRAPPED_GetString(unsigned long id);
@@ -1267,6 +1272,7 @@ interface ParameterMetadata {
     [Ref] ParameterMetadata SetDefaultValue([Const] DOMString defaultValue_);
     boolean STATIC_IsObject([Const] DOMString param);
     boolean STATIC_IsBehavior([Const] DOMString param);
+    boolean STATIC_IsExpression([Const] DOMString type_, [Const] DOMString parameterType);
 
     void SerializeTo([Ref] SerializerElement element);
     void UnserializeFrom([Const, Ref] SerializerElement element);
@@ -2083,7 +2089,7 @@ interface ExpressionParser2NodeWorker {
 };
 
 interface ExpressionValidator {
-    void ExpressionValidator();
+    void ExpressionValidator([Const, Ref] Platform platform, [Const, Ref] ObjectsContainer globalObjectsContainer, [Const, Ref] ObjectsContainer objectsContainer, [Const] DOMString rootType);
 
     [Const, Ref] VectorExpressionParserDiagnostic GetErrors();
 
@@ -2117,7 +2123,7 @@ interface VectorExpressionCompletionDescription {
 };
 
 interface ExpressionCompletionFinder {
-    [Value] VectorExpressionCompletionDescription STATIC_GetCompletionDescriptionsFor([Ref] ExpressionNode node, unsigned long location);
+    [Value] VectorExpressionCompletionDescription STATIC_GetCompletionDescriptionsFor([Const, Ref] Platform platform, [Const, Ref] ObjectsContainer globalObjectsContainer, [Const, Ref] ObjectsContainer objectsContainer, [Const] DOMString rootType, [Ref] ExpressionNode node, unsigned long location);
 
     [Const, Ref] VectorExpressionCompletionDescription GetCompletionDescriptions();
 
@@ -2133,9 +2139,9 @@ interface UniquePtrExpressionNode {
 };
 
 interface ExpressionParser2 {
-    void ExpressionParser2([Const, Ref] Platform platform, [Const, Ref] ObjectsContainer globalObjectsContainer, [Const, Ref] ObjectsContainer objectsContainer);
+    void ExpressionParser2();
 
-    [Value] UniquePtrExpressionNode ParseExpression([Const] DOMString type, [Const] DOMString expression);
+    [Value] UniquePtrExpressionNode ParseExpression([Const] DOMString expression);
 };
 
 enum EventsFunction_FunctionType {

GDevelop.js/Bindings/Wrapper.cpp

@@ -498,6 +498,7 @@ typedef ExtensionAndMetadata<ExpressionMetadata> ExtensionAndExpressionMetadata;
 #define STATIC_FromJSON(x) FromJSON(x)
 #define STATIC_IsObject IsObject
 #define STATIC_IsBehavior IsBehavior
+#define STATIC_IsExpression IsExpression
 #define STATIC_Get Get
 #define STATIC_GetAllUseless GetAllUseless
 #define STATIC_RemoveAllUseless RemoveAllUseless

GDevelop.js/__tests__/Core.js

@@ -1954,9 +1954,9 @@ describe('libGD.js', function () {
       let instr = new gd.Instruction();
       instr.setParametersCount(3);
       expect(instr.getParametersCount()).toBe(3);
-      expect(instr.getParameter(1)).toBe('');
+      expect(instr.getParameter(1).getPlainString()).toBe('');
       instr.setParameter(2, 'MyValue');
-      expect(instr.getParameter(2)).toBe('MyValue');
+      expect(instr.getParameter(2).getPlainString()).toBe('MyValue');
       instr.delete();
     });
     it('can be cloned', function () {
@@ -1966,14 +1966,14 @@ describe('libGD.js', function () {
 
       let newInstr = instr.clone();
       expect(newInstr.getParametersCount()).toBe(3);
-      expect(newInstr.getParameter(1)).toBe('');
-      expect(newInstr.getParameter(2)).toBe('MyValue');
+      expect(newInstr.getParameter(1).getPlainString()).toBe('');
+      expect(newInstr.getParameter(2).getPlainString()).toBe('MyValue');
 
       newInstr.setParameter(2, 'MyChangedValue');
-      expect(instr.getParameter(2)).toBe('MyValue');
-      expect(newInstr.getParameter(2)).toBe('MyChangedValue');
+      expect(instr.getParameter(2).getPlainString()).toBe('MyValue');
+      expect(newInstr.getParameter(2).getPlainString()).toBe('MyChangedValue');
       newInstr.delete();
-      expect(instr.getParameter(2)).toBe('MyValue');
+      expect(instr.getParameter(2).getPlainString()).toBe('MyValue');
 
       instr.delete();
     });
@@ -2065,9 +2065,9 @@ describe('libGD.js', function () {
       expect(list2.get(1).getType()).toBe('Type2');
       expect(list2.get(0).getParametersCount()).toBe(2);
       expect(list2.get(1).getParametersCount()).toBe(1);
-      expect(list2.get(0).getParameter(0)).toBe('Param1');
-      expect(list2.get(0).getParameter(1)).toBe('Param2');
-      expect(list2.get(1).getParameter(0)).toBe('Param3');
+      expect(list2.get(0).getParameter(0).getPlainString()).toBe('Param1');
+      expect(list2.get(0).getParameter(1).getPlainString()).toBe('Param2');
+      expect(list2.get(1).getParameter(0).getPlainString()).toBe('Param3');
 
       list2.delete();
       project.delete();
@@ -3289,18 +3289,36 @@ describe('libGD.js', function () {
       type,
       expression,
       expectedError,
-      expectedErrorPosition
+      expectedErrorPosition,
+      expectedError2,
+      expectedErrorPosition2
     ) {
-      const parser = new gd.ExpressionParser2(
+      const parser = new gd.ExpressionParser2();
+      const expressionNode = parser.parseExpression(expression).get();
+
+      const expressionValidator = new gd.ExpressionValidator(
         gd.JsPlatform.get(),
         project,
-        layout
-      );
-      const expressionNode = parser.parseExpression(type, expression).get();
-
-      const expressionValidator = new gd.ExpressionValidator();
+        layout,
+        type);
       expressionNode.visit(expressionValidator);
-      if (expectedError) {
+      if (expectedError2) {
+        expect(expressionValidator.getErrors().size()).toBe(2);
+        expect(expressionValidator.getErrors().at(0).getMessage()).toBe(
+          expectedError
+        );
+        if (expectedErrorPosition)
+          expect(expressionValidator.getErrors().at(0).getStartPosition()).toBe(
+            expectedErrorPosition
+          );
+        expect(expressionValidator.getErrors().at(1).getMessage()).toBe(
+          expectedError2
+        );
+        if (expectedErrorPosition2)
+          expect(expressionValidator.getErrors().at(1).getStartPosition()).toBe(
+            expectedErrorPosition2
+          );
+      } else if (expectedError) {
         expect(expressionValidator.getErrors().size()).toBe(1);
         expect(expressionValidator.getErrors().at(0).getMessage()).toBe(
           expectedError
@@ -3361,6 +3379,8 @@ describe('libGD.js', function () {
       testExpression(
         'number',
         '3..14',
+        'More than one term was found. Verify that your expression is properly written.',
+        2,
         'No operator found. Did you forget to enter an operator (like +, -, * or /) between numbers or expressions?',
         2
       );
@@ -3410,12 +3430,12 @@ describe('libGD.js', function () {
       testExpression(
         'number',
         'abs(-5, 3)',
-        "This parameter was not expected by this expression. Remove it or verify that you've entered the proper expression name."
+        "This parameter was not expected by this expression. Remove it or verify that you've entered the proper expression name. The number of parameters must be exactly 1"
       );
       testExpression(
         'number',
         'MouseX("", 0, 0) + 1',
-        "This parameter was not expected by this expression. Remove it or verify that you've entered the proper expression name."
+        "This parameter was not expected by this expression. Remove it or verify that you've entered the proper expression name. The number of parameters must be: 0-2"
       );
     });
 
@@ -3434,7 +3454,7 @@ describe('libGD.js', function () {
       testExpression(
         'number',
         'MySpriteObject.PointX("Point", 2)',
-        "This parameter was not expected by this expression. Remove it or verify that you've entered the proper expression name."
+        "This parameter was not expected by this expression. Remove it or verify that you've entered the proper expression name. The number of parameters must be exactly 1"
       );
     });
 
@@ -3465,14 +3485,14 @@ describe('libGD.js', function () {
       }
       const expression = expressionWithCaret.replace('|', '');
 
-      const parser = new gd.ExpressionParser2(
-        gd.JsPlatform.get(),
-        project,
-        layout
-      );
-      const expressionNode = parser.parseExpression(type, expression).get();
+      const parser = new gd.ExpressionParser2();
+      const expressionNode = parser.parseExpression(expression).get();
       const completionDescriptions =
         gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+          gd.JsPlatform.get(),
+          project,
+          layout,
+          type,
           expressionNode,
           // We're looking for completion for the character just before the caret.
           Math.max(0, caretPosition - 1)

GDevelop.js/types/gdexpression.js

@@ -0,0 +1,7 @@
+// Automatically generated by GDevelop.js/scripts/generate-types.js
+declare class gdExpression {
+  getPlainString(): string;
+  getRootNode(): gdExpressionNode;
+  delete(): void;
+  ptr: number;
+};

GDevelop.js/types/gdexpressioncompletionfinder.js

@@ -1,6 +1,6 @@
 // Automatically generated by GDevelop.js/scripts/generate-types.js
 declare class gdExpressionCompletionFinder {
-  static getCompletionDescriptionsFor(node: gdExpressionNode, location: number): gdVectorExpressionCompletionDescription;
+  static getCompletionDescriptionsFor(platform: gdPlatform, globalObjectsContainer: gdObjectsContainer, objectsContainer: gdObjectsContainer, rootType: string, node: gdExpressionNode, location: number): gdVectorExpressionCompletionDescription;
   getCompletionDescriptions(): gdVectorExpressionCompletionDescription;
   delete(): void;
   ptr: number;

GDevelop.js/types/gdexpressionparser2.js

@@ -1,7 +1,7 @@
 // Automatically generated by GDevelop.js/scripts/generate-types.js
 declare class gdExpressionParser2 {
-  constructor(platform: gdPlatform, globalObjectsContainer: gdObjectsContainer, objectsContainer: gdObjectsContainer): void;
-  parseExpression(type: string, expression: string): gdUniquePtrExpressionNode;
+  constructor(): void;
+  parseExpression(expression: string): gdUniquePtrExpressionNode;
   delete(): void;
   ptr: number;
 };

GDevelop.js/types/gdexpressionvalidator.js

@@ -1,6 +1,6 @@
 // Automatically generated by GDevelop.js/scripts/generate-types.js
 declare class gdExpressionValidator extends gdExpressionParser2NodeWorker {
-  constructor(): void;
+  constructor(platform: gdPlatform, globalObjectsContainer: gdObjectsContainer, objectsContainer: gdObjectsContainer, rootType: string): void;
   getErrors(): gdVectorExpressionParserDiagnostic;
   delete(): void;
   ptr: number;

GDevelop.js/types/gdinstruction.js

@@ -7,7 +7,7 @@ declare class gdInstruction {
   setInverted(inverted: boolean): void;
   isInverted(): boolean;
   setParameter(id: number, value: string): void;
-  getParameter(id: number): string;
+  getParameter(id: number): gdExpression;
   setParametersCount(count: number): void;
   getParametersCount(): number;
   getSubInstructions(): gdInstructionsList;

GDevelop.js/types/gdparametermetadata.js

@@ -19,6 +19,7 @@ declare class gdParameterMetadata {
   setDefaultValue(defaultValue_: string): gdParameterMetadata;
   static isObject(param: string): boolean;
   static isBehavior(param: string): boolean;
+  static isExpression(type_: string, parameterType: string): boolean;
   serializeTo(element: gdSerializerElement): void;
   unserializeFrom(element: gdSerializerElement): void;
   delete(): void;

GDevelop.js/types/libgdevelop.js

@@ -104,6 +104,7 @@ declare class libGDevelop {
   Serializer: Class<gdSerializer>;
   InstructionsList: Class<gdInstructionsList>;
   Instruction: Class<gdInstruction>;
+  Expression: Class<gdExpression>;
   VectorPairStringTextFormatting: Class<gdVectorPairStringTextFormatting>;
   TextFormatting: Class<gdTextFormatting>;
   InstructionSentenceFormatter: Class<gdInstructionSentenceFormatter>;

newIDE/app/src/EventsSheet/EventsTree/Instruction.js

@@ -44,6 +44,18 @@ const styles = {
     cursor: 'pointer',
     marginBottom: 1,
   },
+  input: {
+    fontFamily: '"Lucida Console", Monaco, monospace',
+    lineHeight: 1.4,
+  },
+  backgroundHighlightingInline: {
+    marginTop: 0, //Properly align with the text field
+    paddingLeft: 0,
+    paddingRight: 0,
+  },
+  textFieldAndHightlightContainer: {
+    position: 'relative',
+  },
 };
 
 export const reactDndInstructionType = 'GD_DRAGGED_INSTRUCTION';
@@ -93,6 +105,9 @@ type Props = {|
 
   screenType: ScreenType,
   windowWidth: WidthType,
+
+  globalObjectsContainer: gdObjectsContainer,
+  objectsContainer: gdObjectsContainer,
 |};
 
 const Instruction = (props: Props) => {
@@ -102,6 +117,8 @@ const Instruction = (props: Props) => {
     onClick,
     onMoveToInstruction,
     onContextMenu,
+    globalObjectsContainer,
+    objectsContainer,
   } = props;
 
   const instrFormatter = React.useMemo(
@@ -149,6 +166,34 @@ const Instruction = (props: Props) => {
 
           const parameterMetadata = metadata.getParameter(parameterIndex);
           const parameterType = parameterMetadata.getType();
+          let expressionIsValid = true;
+          if (
+            gd.ParameterMetadata.isExpression('number', parameterType) ||
+            gd.ParameterMetadata.isExpression('string', parameterType) ||
+            gd.ParameterMetadata.isExpression('variable', parameterType)
+          ) {
+            const expressionNode = instruction
+              .getParameter(parameterIndex)
+              .getRootNode();
+            const expressionValidator = new gd.ExpressionValidator(
+              gd.JsPlatform.get(),
+              globalObjectsContainer,
+              objectsContainer,
+              parameterType
+            );
+            expressionNode.visit(expressionValidator);
+            expressionIsValid = expressionValidator.getErrors().size() === 0;
+          } else if (gd.ParameterMetadata.isObject(parameterType)) {
+            const objectOrGroupName = instruction
+              .getParameter(parameterIndex)
+              .getPlainString();
+            expressionIsValid =
+              globalObjectsContainer.hasObjectNamed(objectOrGroupName) ||
+              objectsContainer.hasObjectNamed(objectOrGroupName) ||
+              globalObjectsContainer.getObjectGroups().has(objectOrGroupName) ||
+              objectsContainer.getObjectGroups().has(objectOrGroupName);
+          }
+
           return (
             <span
               key={i}
@@ -177,6 +222,7 @@ const Instruction = (props: Props) => {
             >
               {ParameterRenderingService.renderInlineParameter({
                 value: formattedTexts.getString(i),
+                expressionIsValid,
                 parameterMetadata,
                 renderObjectThumbnail,
                 InvalidParameterValue,
@@ -352,6 +398,8 @@ const Instruction = (props: Props) => {
                 renderObjectThumbnail={props.renderObjectThumbnail}
                 screenType={props.screenType}
                 windowWidth={props.windowWidth}
+                globalObjectsContainer={props.globalObjectsContainer}
+                objectsContainer={props.objectsContainer}
               />
             )}
           </React.Fragment>

newIDE/app/src/EventsSheet/EventsTree/InstructionsList.js

@@ -48,6 +48,9 @@ type Props = {
 
   screenType: ScreenType,
   windowWidth: WidthType,
+
+  globalObjectsContainer: gdObjectsContainer,
+  objectsContainer: gdObjectsContainer,
 };
 
 const DropTarget = makeDropTarget<{
@@ -74,6 +77,8 @@ export default function InstructionsList({
   renderObjectThumbnail,
   screenType,
   windowWidth,
+  globalObjectsContainer,
+  objectsContainer,
 }: Props) {
   const [canPaste, setCanPaste] = React.useState(false);
 
@@ -143,6 +148,8 @@ export default function InstructionsList({
         renderObjectThumbnail={renderObjectThumbnail}
         screenType={screenType}
         windowWidth={windowWidth}
+        globalObjectsContainer={globalObjectsContainer}
+        objectsContainer={objectsContainer}
       />
     );
   });

newIDE/app/src/EventsSheet/EventsTree/Renderers/ForEachChildVariableEvent.js

@@ -299,6 +299,8 @@ export default class ForEachChildVariableEvent extends React.Component<
               renderObjectThumbnail={this.props.renderObjectThumbnail}
               screenType={this.props.screenType}
               windowWidth={this.props.windowWidth}
+              globalObjectsContainer={this.props.globalObjectsContainer}
+              objectsContainer={this.props.objectsContainer}
             />
           )}
           renderActionsList={({ className }) => (
@@ -327,6 +329,8 @@ export default class ForEachChildVariableEvent extends React.Component<
               renderObjectThumbnail={this.props.renderObjectThumbnail}
               screenType={this.props.screenType}
               windowWidth={this.props.windowWidth}
+              globalObjectsContainer={this.props.globalObjectsContainer}
+              objectsContainer={this.props.objectsContainer}
             />
           )}
         />

newIDE/app/src/EventsSheet/EventsTree/Renderers/ForEachEvent.js

@@ -156,6 +156,8 @@ export default class ForEachEvent extends React.Component<
               renderObjectThumbnail={this.props.renderObjectThumbnail}
               screenType={this.props.screenType}
               windowWidth={this.props.windowWidth}
+              globalObjectsContainer={this.props.globalObjectsContainer}
+              objectsContainer={this.props.objectsContainer}
             />
           )}
           renderActionsList={({ className }) => (
@@ -184,6 +186,8 @@ export default class ForEachEvent extends React.Component<
               renderObjectThumbnail={this.props.renderObjectThumbnail}
               screenType={this.props.screenType}
               windowWidth={this.props.windowWidth}
+              globalObjectsContainer={this.props.globalObjectsContainer}
+              objectsContainer={this.props.objectsContainer}
             />
           )}
         />

newIDE/app/src/EventsSheet/EventsTree/Renderers/RepeatEvent.js

@@ -155,6 +155,8 @@ export default class RepeatEvent extends React.Component<
               renderObjectThumbnail={this.props.renderObjectThumbnail}
               screenType={this.props.screenType}
               windowWidth={this.props.windowWidth}
+              globalObjectsContainer={this.props.globalObjectsContainer}
+              objectsContainer={this.props.objectsContainer}
             />
           )}
           renderActionsList={({ className }) => (
@@ -183,6 +185,8 @@ export default class RepeatEvent extends React.Component<
               renderObjectThumbnail={this.props.renderObjectThumbnail}
               screenType={this.props.screenType}
               windowWidth={this.props.windowWidth}
+              globalObjectsContainer={this.props.globalObjectsContainer}
+              objectsContainer={this.props.objectsContainer}
             />
           )}
         />

newIDE/app/src/EventsSheet/EventsTree/Renderers/StandardEvent.js

@@ -53,6 +53,8 @@ export default class StandardEvent extends React.Component<
             renderObjectThumbnail={this.props.renderObjectThumbnail}
             screenType={this.props.screenType}
             windowWidth={this.props.windowWidth}
+            globalObjectsContainer={this.props.globalObjectsContainer}
+            objectsContainer={this.props.objectsContainer}
           />
         )}
         renderActionsList={({ className }) => (
@@ -79,6 +81,8 @@ export default class StandardEvent extends React.Component<
             renderObjectThumbnail={this.props.renderObjectThumbnail}
             screenType={this.props.screenType}
             windowWidth={this.props.windowWidth}
+            globalObjectsContainer={this.props.globalObjectsContainer}
+            objectsContainer={this.props.objectsContainer}
           />
         )}
       />

newIDE/app/src/EventsSheet/EventsTree/Renderers/WhileEvent.js

@@ -71,6 +71,8 @@ export default class ForEachEvent extends React.Component<
           renderObjectThumbnail={this.props.renderObjectThumbnail}
           screenType={this.props.screenType}
           windowWidth={this.props.windowWidth}
+          globalObjectsContainer={this.props.globalObjectsContainer}
+          objectsContainer={this.props.objectsContainer}
         />
         <div
           className={classNames({
@@ -104,6 +106,8 @@ export default class ForEachEvent extends React.Component<
               renderObjectThumbnail={this.props.renderObjectThumbnail}
               screenType={this.props.screenType}
               windowWidth={this.props.windowWidth}
+              globalObjectsContainer={this.props.globalObjectsContainer}
+              objectsContainer={this.props.objectsContainer}
             />
           )}
           renderActionsList={({ className }) => (
@@ -132,6 +136,8 @@ export default class ForEachEvent extends React.Component<
               renderObjectThumbnail={this.props.renderObjectThumbnail}
               screenType={this.props.screenType}
               windowWidth={this.props.windowWidth}
+              globalObjectsContainer={this.props.globalObjectsContainer}
+              objectsContainer={this.props.objectsContainer}
             />
           )}
         />

newIDE/app/src/EventsSheet/InlineParameterEditor.js

@@ -123,7 +123,7 @@ export default class InlineParameterEditor extends React.Component<
         instruction,
         instructionMetadata,
         objectParameterIndex !== -1
-          ? instruction.getParameter(objectParameterIndex)
+          ? instruction.getParameter(objectParameterIndex).getPlainString()
           : null
       );
     }
@@ -150,7 +150,9 @@ export default class InlineParameterEditor extends React.Component<
           instructionMetadata={this.state.instructionMetadata}
           parameterMetadata={this.state.parameterMetadata}
           parameterIndex={this.props.parameterIndex}
-          value={instruction.getParameter(this.props.parameterIndex)}
+          value={instruction
+            .getParameter(this.props.parameterIndex)
+            .getPlainString()}
           onChange={this.props.onChange}
           onRequestClose={this.props.onRequestClose}
           onApply={this._onApply}

newIDE/app/src/EventsSheet/InstructionEditor/InstructionParametersEditor.js

@@ -323,9 +323,12 @@ export default class InstructionParametersEditor extends React.Component<
                         instruction={instruction}
                         parameterMetadata={parameterMetadata}
                         parameterIndex={i}
-                        value={instruction.getParameter(i)}
+                        value={instruction.getParameter(i).getPlainString()}
                         onChange={value => {
-                          if (instruction.getParameter(i) !== value) {
+                          if (
+                            instruction.getParameter(i).getPlainString() !==
+                            value
+                          ) {
                             instruction.setParameter(i, value);
                             this.setState({
                               isDirty: true,

newIDE/app/src/EventsSheet/InstructionEditor/NewInstructionEditor.js

@@ -145,7 +145,7 @@ export const useNewInstructionEditor = ({
         );
         if (objectParameterIndex !== -1) {
           return getChosenObjectState(
-            instruction.getParameter(objectParameterIndex),
+            instruction.getParameter(objectParameterIndex).getPlainString(),
             false /* Even if the instruction is invalid for the object, show it as it's what we have already */
           );
         }

newIDE/app/src/EventsSheet/ParameterFields/DefaultField.js

@@ -39,12 +39,16 @@ export default class DefaultField extends React.Component<
 
 export const renderInlineDefaultField = ({
   value,
+  expressionIsValid,
   parameterMetadata,
+  InvalidParameterValue,
   MissingParameterValue,
 }: ParameterInlineRendererProps) => {
   if (!value && !parameterMetadata.isOptional()) {
     return <MissingParameterValue />;
   }
-
+  if (!expressionIsValid) {
+    return <InvalidParameterValue>{value}</InvalidParameterValue>;
+  }
   return value;
 };

newIDE/app/src/EventsSheet/ParameterFields/GenericExpressionField/index.js

@@ -116,12 +116,21 @@ type Props = {|
 const MAX_ERRORS_COUNT = 10;
 
 const extractErrors = (
+  platform: gdPlatform,
+  globalObjectsContainer: gdObjectsContainer,
+  objectsContainer: gdObjectsContainer,
+  expressionType: string,
   expressionNode: gdExpressionNode
 ): {|
   errorText: ?string,
   errorHighlights: Array<Highlight>,
 |} => {
-  const expressionValidator = new gd.ExpressionValidator();
+  const expressionValidator = new gd.ExpressionValidator(
+    gd.JsPlatform.get(),
+    globalObjectsContainer,
+    objectsContainer,
+    expressionType
+  );
   expressionNode.visit(expressionValidator);
   const errors = expressionValidator.getErrors();
 
@@ -370,17 +379,17 @@ export default class ExpressionField extends React.Component<Props, State> {
     // Parsing can be time consuming (~1ms for simple expression,
     // a few milliseconds for complex ones).
 
-    const parser = new gd.ExpressionParser2(
+    const parser = new gd.ExpressionParser2();
+
+    const expressionNode = parser.parseExpression(expression).get();
+
+    const { errorText, errorHighlights } = extractErrors(
       gd.JsPlatform.get(),
       globalObjectsContainer,
-      objectsContainer
+      objectsContainer,
+      expressionType,
+      expressionNode
     );
-
-    const expressionNode = parser
-      .parseExpression(expressionType, expression)
-      .get();
-
-    const { errorText, errorHighlights } = extractErrors(expressionNode);
     const extraErrorText = onExtractAdditionalErrors
       ? onExtractAdditionalErrors(expression, expressionNode)
       : null;
@@ -406,6 +415,10 @@ export default class ExpressionField extends React.Component<Props, State> {
       ? this._inputElement.selectionStart
       : 0;
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      globalObjectsContainer,
+      objectsContainer,
+      expressionType,
       expressionNode,
       cursorPosition - 1
     );

newIDE/app/src/EventsSheet/ParameterFields/ObjectField.js

@@ -88,6 +88,8 @@ export const renderInlineObjectWithThumbnail = ({
   value,
   parameterMetadata,
   renderObjectThumbnail,
+  expressionIsValid,
+  InvalidParameterValue,
   MissingParameterValue,
 }: ParameterInlineRendererProps) => {
   if (!value && !parameterMetadata.isOptional()) {
@@ -102,7 +104,11 @@ export const renderInlineObjectWithThumbnail = ({
       })}
     >
       {renderObjectThumbnail(value)}
-      {value}
+      {expressionIsValid ? (
+        value
+      ) : (
+        <InvalidParameterValue>{value}</InvalidParameterValue>
+      )}
     </span>
   );
 };

newIDE/app/src/EventsSheet/ParameterFields/ParameterInlineRenderer.flow.js

@@ -12,6 +12,7 @@ export type InvalidParameterValueProps = {|
 export type ParameterInlineRendererProps = {|
   parameterMetadata: gdParameterMetadata,
   value: string,
+  expressionIsValid: boolean,
   renderObjectThumbnail: string => React.Node,
   InvalidParameterValue: InvalidParameterValueProps => React.Node,
   MissingParameterValue: () => React.Node,

newIDE/app/src/EventsSheet/ParameterFields/ParameterMetadataTools.js

@@ -39,7 +39,9 @@ export const getLastObjectParameterValue = ({
       objectParameterIndex >= 0 &&
       objectParameterIndex < instruction.getParametersCount()
     ) {
-      objectName = instruction.getParameter(objectParameterIndex);
+      objectName = instruction
+        .getParameter(objectParameterIndex)
+        .getPlainString();
     }
   } else if (expressionMetadata && expression) {
     const objectParameterIndex = gd.ParameterMetadataTools.getObjectParameterIndexFor(
@@ -95,7 +97,7 @@ export const getPreviousParameterValue = ({
       parameterIndex >= 1 &&
       parameterIndex < instruction.getParametersCount()
     ) {
-      return instruction.getParameter(parameterIndex - 1);
+      return instruction.getParameter(parameterIndex - 1).getPlainString();
     }
   } else if (expression) {
     if (

newIDE/app/src/EventsSheet/ParameterFields/VariableField.js

@@ -203,6 +203,8 @@ export const renderVariableWithIcon = (
   {
     value,
     parameterMetadata,
+    expressionIsValid,
+    InvalidParameterValue,
     MissingParameterValue,
   }: ParameterInlineRendererProps,
   iconPath: string,
@@ -229,7 +231,11 @@ export const renderVariableWithIcon = (
         src={iconPath}
         alt=""
       />
-      {value}
+      {expressionIsValid ? (
+        value
+      ) : (
+        <InvalidParameterValue>{value}</InvalidParameterValue>
+      )}
     </span>
   );
 };

newIDE/app/src/ExpressionAutocompletion/ExpressionAutocompletion.spec.js

@@ -47,11 +47,7 @@ const makeTestContext = () => {
     'Draggable'
   );
 
-  const parser = new gd.ExpressionParser2(
-    gd.JsPlatform.get(),
-    project,
-    testLayout
-  );
+  const parser = new gd.ExpressionParser2();
 
   return {
     project,
@@ -65,8 +61,12 @@ describe('ExpressionAutocompletion', () => {
     const { project, testLayout, parser } = makeTestContext();
     const scope = { layout: testLayout };
 
-    const expressionNode = parser.parseExpression('number', 'My').get();
+    const expressionNode = parser.parseExpression('My').get();
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode,
       1
     );
@@ -96,10 +96,12 @@ describe('ExpressionAutocompletion', () => {
       ])
     );
 
-    const expressionNode2 = parser
-      .parseExpression('number', 'MySpriteObjectW')
-      .get();
+    const expressionNode2 = parser.parseExpression('MySpriteObjectW').get();
     const completionDescriptions2 = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode2,
       1
     );
@@ -129,8 +131,12 @@ describe('ExpressionAutocompletion', () => {
     const { project, testLayout, parser } = makeTestContext();
     const scope = { layout: testLayout };
 
-    const expressionNode = parser.parseExpression('number', 'To').get();
+    const expressionNode = parser.parseExpression('To').get();
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode,
       1
     );
@@ -169,8 +175,12 @@ describe('ExpressionAutocompletion', () => {
     const { project, testLayout, parser } = makeTestContext();
     const scope = { layout: testLayout };
 
-    const expressionNode = parser.parseExpression('number', 'MouseX("Ba').get();
+    const expressionNode = parser.parseExpression('MouseX("Ba').get();
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode,
       9
     );
@@ -198,10 +208,12 @@ describe('ExpressionAutocompletion', () => {
     const { project, testLayout, parser } = makeTestContext();
     const scope = { layout: testLayout };
 
-    const expressionNode = parser
-      .parseExpression('number', 'MySpriteObject.Po')
-      .get();
+    const expressionNode = parser.parseExpression('MySpriteObject.Po').get();
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode,
       16
     );
@@ -236,9 +248,13 @@ describe('ExpressionAutocompletion', () => {
     const scope = { layout: testLayout };
 
     const expressionNode = parser
-      .parseExpression('number', 'MySpriteObject.PointX("He')
+      .parseExpression('MySpriteObject.PointX("He')
       .get();
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode,
       24
     );
@@ -267,9 +283,13 @@ describe('ExpressionAutocompletion', () => {
     const scope = { layout: testLayout };
 
     const expressionNode = parser
-      .parseExpression('number', 'MySpriteObjectWithBehaviors.Plat')
+      .parseExpression('MySpriteObjectWithBehaviors.Plat')
       .get();
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode,
       28
     );
@@ -299,9 +319,13 @@ describe('ExpressionAutocompletion', () => {
     const scope = { layout: testLayout };
 
     const expressionNode = parser
-      .parseExpression('number', 'MySpriteObjectWithBehaviors.a')
+      .parseExpression('MySpriteObjectWithBehaviors.a')
       .get();
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode,
       28
     );
@@ -336,12 +360,13 @@ describe('ExpressionAutocompletion', () => {
     const scope = { layout: testLayout };
 
     const expressionNode = parser
-      .parseExpression(
-        'number',
-        'MySpriteObjectWithBehaviors.PlatformerObject::Jum'
-      )
+      .parseExpression('MySpriteObjectWithBehaviors.PlatformerObject::Jum')
       .get();
     const completionDescriptions = gd.ExpressionCompletionFinder.getCompletionDescriptionsFor(
+      gd.JsPlatform.get(),
+      project,
+      testLayout,
+      'number',
       expressionNode,
       47
     );

newIDE/app/src/InstructionOrExpression/SetupInstructionParameters.js

@@ -66,9 +66,9 @@ export const setupInstructionParameters = (
       });
 
     if (behaviorNames.length > 0) {
-      const currentParameterValue = instruction.getParameter(
-        maybeBehaviorParameterIndex
-      );
+      const currentParameterValue = instruction
+        .getParameter(maybeBehaviorParameterIndex)
+        .getPlainString();
 
       // Set the behavior to the first matching behavior, in case a matching behavior name
       // is not already set.

newIDE/app/src/InstructionOrExpression/SetupInstructionParameters.spec.js

@@ -35,11 +35,11 @@ describe('setupInstructionParameters', () => {
 
     // Check that parameters were created
     expect(instruction.getParametersCount()).toBe(5);
-    expect(instruction.getParameter(0)).toBe('');
-    expect(instruction.getParameter(1)).toBe('');
-    expect(instruction.getParameter(2)).toBe('');
-    expect(instruction.getParameter(3)).toBe('');
-    expect(instruction.getParameter(4)).toBe('');
+    expect(instruction.getParameter(0).getPlainString()).toBe('');
+    expect(instruction.getParameter(1).getPlainString()).toBe('');
+    expect(instruction.getParameter(2).getPlainString()).toBe('');
+    expect(instruction.getParameter(3).getPlainString()).toBe('');
+    expect(instruction.getParameter(4).getPlainString()).toBe('');
   });
 
   it('sets the proper number of parameters and the object name', () => {
@@ -74,8 +74,8 @@ describe('setupInstructionParameters', () => {
 
     // Check that parameters were created and the object name set
     expect(instruction.getParametersCount()).toBe(2);
-    expect(instruction.getParameter(0)).toBe(objectName);
-    expect(instruction.getParameter(1)).toBe('');
+    expect(instruction.getParameter(0).getPlainString()).toBe(objectName);
+    expect(instruction.getParameter(1).getPlainString()).toBe('');
   });
 
   it('sets the proper parameters for a behavior', () => {
@@ -116,10 +116,12 @@ describe('setupInstructionParameters', () => {
 
     // Check that parameters were created, the object name and behavior set
     expect(instruction.getParametersCount()).toBe(4);
-    expect(instruction.getParameter(0)).toBe(objectName);
-    expect(instruction.getParameter(1)).toBe('PlatformerObject');
-    expect(instruction.getParameter(2)).toBe(''); // In the future, this could be set to a default value.
-    expect(instruction.getParameter(3)).toBe('');
+    expect(instruction.getParameter(0).getPlainString()).toBe(objectName);
+    expect(instruction.getParameter(1).getPlainString()).toBe(
+      'PlatformerObject'
+    );
+    expect(instruction.getParameter(2).getPlainString()).toBe(''); // In the future, this could be set to a default value.
+    expect(instruction.getParameter(3).getPlainString()).toBe('');
   });
 
   it('sets the proper parameters for a behavior, selecting the first behavior if multiple', () => {
@@ -165,8 +167,10 @@ describe('setupInstructionParameters', () => {
 
     // Check that parameters were created, the object name and behavior set
     expect(instruction.getParametersCount()).toBe(4);
-    expect(instruction.getParameter(0)).toBe(objectName);
-    expect(instruction.getParameter(1)).toBe('FirstPlatformerObject');
+    expect(instruction.getParameter(0).getPlainString()).toBe(objectName);
+    expect(instruction.getParameter(1).getPlainString()).toBe(
+      'FirstPlatformerObject'
+    );
   });
 
   it('sets the proper parameters for a behavior, changing it if a wrong behavior name is entered', () => {
@@ -215,8 +219,10 @@ describe('setupInstructionParameters', () => {
 
     // Check that parameters were created, the object name and behavior set
     expect(instruction.getParametersCount()).toBe(4);
-    expect(instruction.getParameter(0)).toBe(objectName);
-    expect(instruction.getParameter(1)).toBe('FirstPlatformerObject');
+    expect(instruction.getParameter(0).getPlainString()).toBe(objectName);
+    expect(instruction.getParameter(1).getPlainString()).toBe(
+      'FirstPlatformerObject'
+    );
   });
 
   it('sets the proper parameters for a behavior, letting an existing behavior name if it is valid', () => {
@@ -265,7 +271,9 @@ describe('setupInstructionParameters', () => {
 
     // Check that parameters were created, the object name and behavior set
     expect(instruction.getParametersCount()).toBe(4);
-    expect(instruction.getParameter(0)).toBe(objectName);
-    expect(instruction.getParameter(1)).toBe('OtherPlatformerObject');
+    expect(instruction.getParameter(0).getPlainString()).toBe(objectName);
+    expect(instruction.getParameter(1).getPlainString()).toBe(
+      'OtherPlatformerObject'
+    );
   });
 });

newIDE/app/src/ResourcesList/ResourceUtils.spec.js

@@ -119,6 +119,7 @@ describe('ResourceUtils', () => {
         .getActions()
         .get(0)
         .getParameter(1)
+        .getPlainString()
     ).toBe('Audio1');
   });
 });