Move declarations up to test

- Don't show in changelog

.circleci/config.yml

@@ -176,6 +176,7 @@ jobs:
 
   # Build the WebAssembly library only (so that it's cached on a S3 and easy to re-use).
   build-gdevelop_js-wasm-only:
+    resource_class: medium+ # Compilation time decrease linearly with the number of CPUs, but not linking (so "large" does not speedup total build time).
     docker:
       - image: cimg/node:16.13
 
@@ -232,10 +233,83 @@ jobs:
           name: Deploy to S3 (latest)
           command: aws s3 sync Binaries/embuild/GDevelop.js s3://gdevelop-gdevelop.js/$(git rev-parse --abbrev-ref HEAD)/latest/
 
+  # Build the WebAssembly library with clang-tidy and memory sanitizers.
+  build-gdevelop_js-debug-sanitizers-and-extra-checks:
+    resource_class: xlarge # Total time decrease linearly with the number of CPUs.
+    docker:
+      - image: cimg/node:16.13
+
+    working_directory: ~/GDevelop
+
+    steps:
+      - checkout
+      - aws-cli/setup
+
+      # System dependencies (for Emscripten)
+      - run:
+          name: Install dependencies for Emscripten
+          command: sudo apt-get update && sudo apt install cmake
+
+      - run:
+          name: Install dependencies for clang-tidy v19
+          command: wget https://apt.llvm.org/llvm.sh && chmod +x llvm.sh && sudo ./llvm.sh 19 && sudo apt install clang-tidy-19
+
+      - run:
+          name: Install Python3 dependencies for Emscripten
+          command: sudo apt install python-is-python3 python3-distutils -y
+
+      - run:
+          name: Install Emscripten (for GDevelop.js)
+          command: git clone https://github.com/juj/emsdk.git && cd emsdk && ./emsdk install 3.1.21 && ./emsdk activate 3.1.21 && cd ..
+
+      # GDevelop.js dependencies
+      - restore_cache:
+          keys:
+            - gdevelop.js-linux-nodejs-dependencies-{{ checksum "GDevelop.js/package-lock.json" }}
+            # fallback to using the latest cache if no exact match is found
+            - gdevelop.js-linux-nodejs-dependencies-
+
+      - run:
+          name: Install GDevelop.js dependencies and build it
+          command: cd GDevelop.js && npm install && cd ..
+
+      # Build GDevelop.js
+      - run:
+          name: Build GDevelop.js ('debug-sanitizers' variant)
+          command: cd GDevelop.js && source ../emsdk/emsdk_env.sh && npm run build -- --variant=debug-sanitizers
+
+      - run:
+          name: Run clang-tidy
+          command: cd GDevelop.js && npm run lint
+
+      - run:
+          name: Run tests
+          command: cd GDevelop.js && npm run test -- --maxWorkers=4
+
+      # Upload artifacts (CircleCI)
+      - store_artifacts:
+          path: Binaries/embuild/GDevelop.js
+
+      # Upload artifacts (AWS)
+      - run:
+          name: Deploy to S3 (specific commit)
+          command: aws s3 sync Binaries/embuild/GDevelop.js s3://gdevelop-gdevelop.js/$(git rev-parse --abbrev-ref HEAD)/variant/debug-sanitizers/commit/$(git rev-parse HEAD)/
+
 workflows:
-  builds:
+  gdevelop_js-wasm:
     jobs:
       - build-gdevelop_js-wasm-only
+  gdevelop_js-wasm-extra-checks:
+    jobs:
+      - build-gdevelop_js-debug-sanitizers-and-extra-checks:
+          # Extra checks are resource intensive so don't all run them.
+          filters:
+            branches:
+              only:
+                - master
+                - /experimental-build.*/
+  builds:
+    jobs:
       - build-macos:
           filters:
             branches:

.clang-tidy

@@ -0,0 +1,4 @@
+Checks: 'clang-diagnostic-*,clang-analyzer-*,cppcoreguidelines-*,-cppcoreguidelines-explicit-virtual-functions,-cppcoreguidelines-avoid-const-or-ref-data-members,-cppcoreguidelines-special-member-functions,-cppcoreguidelines-avoid-magic-numbers,-cppcoreguidelines-non-private-member-variables-in-classes,-cppcoreguidelines-owning-memory,-cppcoreguidelines-virtual-class-destructor,-clang-analyzer-optin.performance.Padding,-cppcoreguidelines-narrowing-conversions'
+WarningsAsErrors: 'cppcoreguidelines-pro-type-member-init, clang-analyzer-optin.cplusplus.UninitializedObject'
+HeaderFilterRegex: '.*'
+FormatStyle: none

.github/workflows/gdcore-tools-hook.yml

@@ -0,0 +1,22 @@
+# This worflow notifies arthuro555's gdcore-tools repository when a new release is published.
+#
+# This is used to allow gdcore-tools, a library to use GDCore outside of GDevelop,
+# to attempt to automatically build, test, and publish a release for the new
+# GDevelop version.
+name: Trigger gdcore-tools pipeline
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  dispatch-event:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Repository Dispatch
+        uses: peter-evans/repository-dispatch@v3
+        with:
+          token: ${{ secrets.GDCORE_TOOLS_PAT }}
+          repository: arthuro555/gdcore-tools
+          event-type: gdevelop-release
+          client-payload: '{"release": ${{ toJson(github.event.release) }}}'

CMakeLists.txt

@@ -69,12 +69,18 @@ if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
 	# uninitialized variables or other hard to debug bugs.
 	add_compile_options(
 		-Wall
+		-Wextra
+		-Wuninitialized
+		-Wconditional-uninitialized
 		-Wno-unknown-warning-option
 		-Wno-reorder-ctor
 		-Wno-reorder
+		-Wno-unused-parameter
 		-Wno-pessimizing-move
-		-Wno-unused-variable
+		-Wno-unused-variable # Not a good style, but not a risk
 		-Wno-unused-private-field
+		-Wno-ignored-qualifiers # Not a risk
+		-Wno-sign-compare # Not a big risk
 
 		# Make as much warnings considered as errors as possible (only one for now).
 		-Werror=return-stack-address

Core/GDCore/Events/Builtin/WhileEvent.h

@@ -72,8 +72,6 @@ class GD_CORE_API WhileEvent : public gd::BaseEvent {
                               ///< de/activate infinite loop warning when the
                               ///< user create the event
 
-  mutable unsigned int whileConditionsHeight;
-
   int GetConditionsHeight() const;
   int GetActionsHeight() const;
   int GetWhileConditionsHeight() const;

Core/GDCore/Events/CodeGeneration/DiagnosticReport.h

@@ -14,10 +14,10 @@
 namespace gd {
 
 /**
- * \brief 
+ * \brief
  */
 class GD_CORE_API ProjectDiagnostic {
-public:
+ public:
   enum ErrorType {
     UndeclaredVariable,
     MissingBehavior,
@@ -25,12 +25,17 @@ public:
     MismatchedObjectType,
   };
 
-  ProjectDiagnostic(ErrorType type_, const gd::String &message_,
+  ProjectDiagnostic(ErrorType type_,
+                    const gd::String &message_,
                     const gd::String &actualValue_,
-                    const gd::String &expectedValue_, const gd::String &objectName_ = "")
-      : type(type_), message(message_), actualValue(actualValue_), expectedValue(expectedValue_),
-        objectName(objectName_){};
-  virtual ~ProjectDiagnostic(){};
+                    const gd::String &expectedValue_,
+                    const gd::String &objectName_ = "")
+      : type(type_),
+        message(message_),
+        actualValue(actualValue_),
+        expectedValue(expectedValue_),
+        objectName(objectName_) {};
+  virtual ~ProjectDiagnostic() {};
 
   ErrorType GetType() const { return type; };
   const gd::String &GetMessage() const { return message; }
@@ -38,7 +43,7 @@ public:
   const gd::String &GetActualValue() const { return actualValue; }
   const gd::String &GetExpectedValue() const { return expectedValue; }
 
-private:
+ private:
   ErrorType type;
   gd::String message;
   gd::String objectName;
@@ -47,12 +52,12 @@ private:
 };
 
 /**
- * \brief 
+ * \brief
  */
 class GD_CORE_API DiagnosticReport {
-public:
-  DiagnosticReport(){};
-  virtual ~DiagnosticReport(){};
+ public:
+  DiagnosticReport() {};
+  virtual ~DiagnosticReport() {};
 
   void Add(const gd::ProjectDiagnostic &projectDiagnostic) {
     projectDiagnostics.push_back(
@@ -67,32 +72,39 @@ public:
 
   const gd::String &GetSceneName() const { return sceneName; }
 
-  void SetSceneName(const gd::String &sceneName_) {
-    sceneName = sceneName_;
+  void SetSceneName(const gd::String &sceneName_) { sceneName = sceneName_; }
+
+  void LogAllDiagnostics() {
+    for (auto &diagnostic : projectDiagnostics) {
+      std::cout << diagnostic->GetMessage()
+                << "(object: " << diagnostic->GetObjectName()
+                << ", actual value: " << diagnostic->GetActualValue()
+                << ", expected value: " << diagnostic->GetExpectedValue() << ")"
+                << std::endl;
+    }
   }
 
-private:
+ private:
   std::vector<std::unique_ptr<gd::ProjectDiagnostic>> projectDiagnostics;
   gd::String sceneName;
 };
 
 /**
- * \brief 
+ * \brief
  */
 class GD_CORE_API WholeProjectDiagnosticReport {
-public:
-  WholeProjectDiagnosticReport(){};
-  virtual ~WholeProjectDiagnosticReport(){};
+ public:
+  WholeProjectDiagnosticReport() {};
+  virtual ~WholeProjectDiagnosticReport() {};
 
   const DiagnosticReport &Get(std::size_t index) const {
     return *diagnosticReports[index].get();
   };
 
-  void Clear() {
-    diagnosticReports.clear();
-  };
+  void Clear() { diagnosticReports.clear(); };
 
-  DiagnosticReport& AddNewDiagnosticReportForScene(const gd::String &sceneName) {
+  DiagnosticReport &AddNewDiagnosticReportForScene(
+      const gd::String &sceneName) {
     auto diagnosticReport = gd::make_unique<gd::DiagnosticReport>();
     diagnosticReport->SetSceneName(sceneName);
     diagnosticReports.push_back(std::move(diagnosticReport));
@@ -102,7 +114,7 @@ public:
   std::size_t Count() const { return diagnosticReports.size(); };
 
   bool HasAnyIssue() {
-    for (auto& diagnosticReport : diagnosticReports) {
+    for (auto &diagnosticReport : diagnosticReports) {
       if (diagnosticReport->Count() > 0) {
         return true;
       }
@@ -110,8 +122,8 @@ public:
     return false;
   }
 
-private:
+ private:
   std::vector<std::unique_ptr<gd::DiagnosticReport>> diagnosticReports;
 };
 
-} // namespace gd
+}  // namespace gd

Core/GDCore/Events/CodeGeneration/EventsCodeGenerator.cpp

@@ -345,14 +345,14 @@ gd::String EventsCodeGenerator::GenerateConditionCode(
         gd::ProjectDiagnostic projectDiagnostic(
             gd::ProjectDiagnostic::ErrorType::UnknownObject, "",
             objectInParameter, "");
-        diagnosticReport->Add(projectDiagnostic);
+        if (diagnosticReport) diagnosticReport->Add(projectDiagnostic);
         return "/* Unknown object - skipped. */";
       } else if (!expectedObjectType.empty() &&
                  actualObjectType != expectedObjectType) {
         gd::ProjectDiagnostic projectDiagnostic(
             gd::ProjectDiagnostic::ErrorType::MismatchedObjectType, "",
             actualObjectType, expectedObjectType, objectInParameter);
-        diagnosticReport->Add(projectDiagnostic);
+        if (diagnosticReport) diagnosticReport->Add(projectDiagnostic);
         return "/* Mismatched object type - skipped. */";
       }
     }
@@ -509,7 +509,7 @@ void EventsCodeGenerator::CheckBehaviorParameters(
             gd::ProjectDiagnostic projectDiagnostic(
                 gd::ProjectDiagnostic::ErrorType::MissingBehavior, "",
                 actualBehaviorType, expectedBehaviorType, lastObjectName);
-            diagnosticReport->Add(projectDiagnostic);
+            if (diagnosticReport) diagnosticReport->Add(projectDiagnostic);
           }
         }
       });
@@ -567,14 +567,14 @@ gd::String EventsCodeGenerator::GenerateActionCode(
         gd::ProjectDiagnostic projectDiagnostic(
             gd::ProjectDiagnostic::ErrorType::UnknownObject, "",
             objectInParameter, "");
-        diagnosticReport->Add(projectDiagnostic);
+        if (diagnosticReport) diagnosticReport->Add(projectDiagnostic);
         return "/* Unknown object - skipped. */";
       } else if (!expectedObjectType.empty() &&
                  actualObjectType != expectedObjectType) {
         gd::ProjectDiagnostic projectDiagnostic(
             gd::ProjectDiagnostic::ErrorType::MismatchedObjectType, "",
             actualObjectType, expectedObjectType, objectInParameter);
-        diagnosticReport->Add(projectDiagnostic);
+        if (diagnosticReport) diagnosticReport->Add(projectDiagnostic);
         return "/* Mismatched object type - skipped. */";
       }
     }

Core/GDCore/Events/Parsers/ExpressionParser2Node.h

@@ -36,8 +36,8 @@ struct GD_CORE_API ExpressionParserLocation {
 
  private:
   bool isValid;
-  size_t startPosition;
-  size_t endPosition;
+  size_t startPosition = 0;
+  size_t endPosition = 0;
 };
 
 /**

Core/GDCore/Extensions/Builtin/MouseExtension.cpp

@@ -338,6 +338,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsMouseExtension(
       .AddParameter("expression", _("Camera number (default : 0)"), "", true)
       .SetDefaultValue("0");
 
+  // Deprecated
   extension
       .AddCondition(
           "PopStartedTouch",
@@ -354,6 +355,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsMouseExtension(
       .AddCodeOnlyParameter("currentScene", "")
       .SetHidden();
 
+  // Deprecated
   extension
       .AddCondition(
           "PopEndedTouch",
@@ -370,6 +372,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsMouseExtension(
       .AddCodeOnlyParameter("currentScene", "")
       .SetHidden();
 
+  // Deprecated
   extension
       .AddCondition(
           "HasAnyTouchStarted",

Core/GDCore/Extensions/Metadata/BehaviorMetadata.cpp

@@ -37,8 +37,7 @@ BehaviorMetadata::BehaviorMetadata(
       className(className_),
       iconFilename(icon24x24),
       instance(instance_),
-      sharedDatasInstance(sharedDatasInstance_),
-      quickCustomizationVisibility(QuickCustomization::Visibility::Default) {
+      sharedDatasInstance(sharedDatasInstance_) {
   SetFullName(gd::String(fullname_));
   SetDescription(gd::String(description_));
   SetDefaultName(gd::String(defaultName_));

Core/GDCore/Extensions/Metadata/BehaviorMetadata.h

@@ -394,7 +394,7 @@ class GD_CORE_API BehaviorMetadata : public InstructionOrExpressionContainerMeta
   bool isPrivate = false;
   bool isHidden = false;
   gd::String openFullEditorLabel;
-  QuickCustomization::Visibility quickCustomizationVisibility;
+  QuickCustomization::Visibility quickCustomizationVisibility = QuickCustomization::Visibility::Default;
 
   // TODO: Nitpicking: convert these to std::unique_ptr to clarify ownership.
   std::shared_ptr<gd::Behavior> instance;

Core/GDCore/Extensions/Metadata/EffectMetadata.h

@@ -185,10 +185,10 @@ class GD_CORE_API EffectMetadata {
   gd::String fullname;
   gd::String description;
   std::vector<gd::String> includeFiles;
-  bool isMarkedAsNotWorkingForObjects;
-  bool isMarkedAsOnlyWorkingFor2D;
-  bool isMarkedAsOnlyWorkingFor3D;
-  bool isMarkedAsUnique;
+  bool isMarkedAsNotWorkingForObjects = false;
+  bool isMarkedAsOnlyWorkingFor2D = false;
+  bool isMarkedAsOnlyWorkingFor3D = false;
+  bool isMarkedAsUnique = false;
   std::map<gd::String, gd::PropertyDescriptor> properties;
 };
 

Core/GDCore/Extensions/Metadata/EventMetadata.cpp

@@ -19,7 +19,8 @@ EventMetadata::EventMetadata(const gd::String &name_,
     : fullname(fullname_),
       description(description_),
       group(group_),
-      instance(instance_) {
+      instance(instance_),
+      hasCustomCodeGenerator(false) {
   ClearCodeGenerationAndPreprocessing();
   if (instance) instance->SetType(name_);
 }

Core/GDCore/Extensions/Metadata/EventMetadata.h

@@ -83,7 +83,7 @@ class GD_CORE_API EventMetadata {
   gd::String group;
 
   std::shared_ptr<gd::BaseEvent> instance;
-  bool hasCustomCodeGenerator;
+  bool hasCustomCodeGenerator = false;
   std::function<gd::String(gd::BaseEvent& event,
                            gd::EventsCodeGenerator& codeGenerator,
                            gd::EventsCodeGenerationContext& context)>

Core/GDCore/Extensions/Metadata/MetadataProvider.h

@@ -288,8 +288,8 @@ class GD_CORE_API MetadataProvider {
   static EffectMetadata badEffectMetadata;
   static gd::InstructionMetadata badInstructionMetadata;
   static gd::ExpressionMetadata badExpressionMetadata;
-  int useless;  // Useless member to avoid emscripten "must have a positive
-                // integer typeid pointer" runtime error.
+  int useless = 0;  // Useless member to avoid emscripten "must have a positive
+                    // integer typeid pointer" runtime error.
 };
 
 }  // namespace gd

Core/GDCore/Extensions/Metadata/ObjectMetadata.h

@@ -246,6 +246,11 @@ class GD_CORE_API ObjectMetadata : public InstructionOrExpressionContainerMetada
     return *this;
   }
 
+  ObjectMetadata& ResetDefaultBehaviorsJustForTesting() {
+    defaultBehaviorTypes.clear();
+    return *this;
+  }
+
   const gd::String& GetName() const override { return name; }
   const gd::String& GetFullName() const override { return fullname; }
   const gd::String& GetCategoryFullName() const { return categoryFullName; }

Core/GDCore/Extensions/Metadata/ParameterMetadataTools.cpp

@@ -6,6 +6,8 @@
 #include "ParameterMetadataTools.h"
 
 #include "GDCore/Events/Expression.h"
+#include "GDCore/Events/Parsers/ExpressionParser2.h"
+#include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Project/Object.h"
 #include "GDCore/Project/ObjectsContainer.h"
 #include "GDCore/Project/ObjectsContainersList.h"
@@ -13,8 +15,6 @@
 #include "GDCore/Project/Project.h"
 #include "GDCore/String.h"
 #include "InstructionMetadata.h"
-#include "GDCore/Events/Parsers/ExpressionParser2.h"
-#include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 
 namespace gd {
 const ParameterMetadata ParameterMetadataTools::badParameterMetadata;
@@ -23,7 +23,10 @@ void ParameterMetadataTools::ParametersToObjectsContainer(
     const gd::Project& project,
     const ParameterMetadataContainer& parameters,
     gd::ObjectsContainer& outputObjectsContainer) {
-  outputObjectsContainer.GetObjects().clear();
+  // Keep track of all objects and their behaviors names, so we can remove
+  // those who are in the container but not in the parameters anymore.
+  std::set<gd::String> allObjectNames;
+  std::map<gd::String, std::set<gd::String>> allObjectNonDefaultBehaviorNames;
 
   gd::String lastObjectName;
   for (std::size_t i = 0; i < parameters.GetParametersCount(); ++i) {
@@ -31,34 +34,97 @@ void ParameterMetadataTools::ParametersToObjectsContainer(
     if (parameter.GetName().empty()) continue;
 
     if (gd::ParameterMetadata::IsObject(parameter.GetType())) {
-      outputObjectsContainer.InsertNewObject(
-          project,
-          parameter.GetExtraInfo(),
-          parameter.GetName(),
-          outputObjectsContainer.GetObjectsCount());
+      const gd::String& objectName = parameter.GetName();
+      const gd::String& objectType = parameter.GetExtraInfo();
+      allObjectNames.insert(objectName);
+
+      // Check if we can keep the existing object.
+      if (outputObjectsContainer.HasObjectNamed(objectName)) {
+        const gd::Object& object = outputObjectsContainer.GetObject(objectName);
+
+        if (object.GetType() != objectType) {
+          // Object type has changed, remove it so it is re-created.
+          outputObjectsContainer.RemoveObject(objectName);
+        }
+      }
+
+      if (outputObjectsContainer.HasObjectNamed(objectName)) {
+        // Keep the existing object, ensure the default behaviors
+        // are all present (and no more than required by the object type).
+        // Non default behaviors coming from parameters will be added or removed later.
+        project.EnsureObjectDefaultBehaviors(outputObjectsContainer.GetObject(objectName));
+      } else {
+        // Create a new object (and its default behaviors) if needed.
+        outputObjectsContainer.InsertNewObject(
+            project,
+            objectType,
+            objectName,
+            outputObjectsContainer.GetObjectsCount());
+      }
 
       // 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.
-      lastObjectName = parameter.GetName();
+      lastObjectName = objectName;
     } else if (gd::ParameterMetadata::IsBehavior(parameter.GetType())) {
       if (!lastObjectName.empty()) {
         if (outputObjectsContainer.HasObjectNamed(lastObjectName)) {
-          const gd::Object& object =
-              outputObjectsContainer.GetObject(lastObjectName);
-          gd::String behaviorName = parameter.GetName();
+          const gd::String& behaviorName = parameter.GetName();
+          const gd::String& behaviorType = parameter.GetExtraInfo();
+
+          gd::Object& object = outputObjectsContainer.GetObject(lastObjectName);
+          allObjectNonDefaultBehaviorNames[lastObjectName].insert(behaviorName);
+
+          // Check if we can keep the existing behavior.
+          if (object.HasBehaviorNamed(behaviorName)) {
+            if (object.GetBehavior(behaviorName).GetTypeName() !=
+                behaviorType) {
+              // Behavior type has changed, remove it so it is re-created.
+              object.RemoveBehavior(behaviorName);
+            }
+          }
 
           if (!object.HasBehaviorNamed(behaviorName)) {
-            outputObjectsContainer.GetObject(lastObjectName)
-                .AddNewBehavior(
-                    project, parameter.GetExtraInfo(), behaviorName);
+            object.AddNewBehavior(
+                project, parameter.GetExtraInfo(), behaviorName);
           }
         }
       }
     }
   }
+
+  // Remove objects that are not in the parameters anymore.
+  std::set<gd::String> objectNamesInContainer =
+      outputObjectsContainer.GetAllObjectNames();
+  for (const auto& objectName : objectNamesInContainer) {
+    if (allObjectNames.find(objectName) == allObjectNames.end()) {
+      outputObjectsContainer.RemoveObject(objectName);
+    }
+  }
+
+  // Remove behaviors of objects that are not in the parameters anymore.
+  for (const auto& objectName : allObjectNames) {
+    if (!outputObjectsContainer.HasObjectNamed(objectName)) {
+      // Should not happen.
+      continue;
+    }
+
+    auto& object = outputObjectsContainer.GetObject(objectName);
+    const auto& allBehaviorNames = allObjectNonDefaultBehaviorNames[objectName];
+    for (const auto& behaviorName : object.GetAllBehaviorNames()) {
+      if (object.GetBehavior(behaviorName).IsDefaultBehavior()) {
+        // Default behaviors are already ensured to be all present
+        // (and no more than required by the object type).
+        continue;
+      }
+
+      if (allBehaviorNames.find(behaviorName) == allBehaviorNames.end()) {
+        object.RemoveBehavior(behaviorName);
+      }
+    }
+  }
 }
 
 void ParameterMetadataTools::ForEachParameterMatchingSearch(

Core/GDCore/Extensions/Metadata/ValueTypeMetadata.cpp

@@ -53,27 +53,32 @@ const gd::String &ValueTypeMetadata::GetExpressionPrimitiveValueType(
 
 const gd::String &
 ValueTypeMetadata::GetPrimitiveValueType(const gd::String &parameterType) {
-  if (parameterType == "variable" ||
-      gd::ValueTypeMetadata::IsTypeExpression("variable", parameterType)) {
-    return ValueTypeMetadata::variableType;
+  if (parameterType == "number" ||
+      gd::ValueTypeMetadata::IsTypeValue("number", parameterType)) {
+    return ValueTypeMetadata::numberType;
   }
-  if (parameterType == "boolean" || parameterType == "yesorno" ||
-      parameterType == "trueorfalse") {
-    return ValueTypeMetadata::booleanType;
-  }
-  // These 2 types are not strings from the code generator point of view,
-  // but it is for event-based extensions.
-  if (parameterType == "key" || parameterType == "mouse") {
+  if (parameterType == "string" ||
+      gd::ValueTypeMetadata::IsTypeValue("string", parameterType)) {
     return ValueTypeMetadata::stringType;
   }
-  return GetExpressionPrimitiveValueType(parameterType);
+  if (parameterType == "variable" ||
+      gd::ValueTypeMetadata::IsTypeValue("variable", parameterType)) {
+    return ValueTypeMetadata::variableType;
+  }
+  if (parameterType == "boolean" ||
+      gd::ValueTypeMetadata::IsTypeValue("boolean", parameterType)) {
+    return ValueTypeMetadata::booleanType;
+  }
+  return parameterType;
 }
 
 const gd::String ValueTypeMetadata::numberValueType = "number";
 const gd::String ValueTypeMetadata::booleanValueType = "boolean";
+const gd::String ValueTypeMetadata::stringValueType = "string";
 const gd::String ValueTypeMetadata::colorValueType = "color";
 const gd::String ValueTypeMetadata::choiceValueType = "stringWithSelector";
-const gd::String ValueTypeMetadata::stringValueType = "string";
+const gd::String ValueTypeMetadata::behaviorValueType = "behavior";
+const gd::String ValueTypeMetadata::leaderboardIdValueType = "leaderboardId";
 
 const gd::String &ValueTypeMetadata::ConvertPropertyTypeToValueType(
     const gd::String &propertyType) {
@@ -85,6 +90,10 @@ const gd::String &ValueTypeMetadata::ConvertPropertyTypeToValueType(
     return colorValueType;
   } else if (propertyType == "Choice") {
     return choiceValueType;
+  } else if (propertyType == "Behavior") {
+    return behaviorValueType;
+  } else if (propertyType == "LeaderboardId") {
+    return leaderboardIdValueType;
   }
   // For "String" or default
   return stringValueType;

Core/GDCore/Extensions/Metadata/ValueTypeMetadata.h

@@ -111,21 +111,21 @@ class GD_CORE_API ValueTypeMetadata {
    * given type.
    */
   bool IsNumber() const {
-    return gd::ValueTypeMetadata::IsTypeExpression("number", name);
+    return gd::ValueTypeMetadata::IsTypeValue("number", name);
   }
 
   /**
    * \brief Return true if the type is a string.
    */
   bool IsString() const {
-    return gd::ValueTypeMetadata::IsTypeExpression("string", name);
+    return gd::ValueTypeMetadata::IsTypeValue("string", name);
   }
 
   /**
    * \brief Return true if the type is a boolean.
    */
   bool IsBoolean() const {
-    return gd::ValueTypeMetadata::IsTypeExpression("boolean", name);
+    return gd::ValueTypeMetadata::IsTypeValue("boolean", name);
   }
 
   /**
@@ -135,7 +135,7 @@ class GD_CORE_API ValueTypeMetadata {
    * and ExpressionAutocompletion) and in the EventsCodeGenerator.
    */
   bool IsVariable() const {
-    return gd::ValueTypeMetadata::IsTypeExpression("variable", name);
+    return gd::ValueTypeMetadata::GetPrimitiveValueType(name) == "variable";
   }
 
   /**
@@ -175,7 +175,9 @@ class GD_CORE_API ValueTypeMetadata {
   }
 
   /**
-   * \brief Return true if the type is an expression of the given type.
+   * \brief Return true if the type is an expression of the given type from the
+   * caller point of view.
+   *
    * \note If you are adding a new type of parameter, also add it in the IDE (
    * see EventsFunctionParametersEditor, ParameterRenderingService
    * and ExpressionAutocompletion) and in the EventsCodeGenerator.
@@ -186,6 +188,7 @@ class GD_CORE_API ValueTypeMetadata {
       return parameterType == "number" || parameterType == "expression" ||
              parameterType == "camera" || parameterType == "forceMultiplier";
     } else if (type == "string") {
+      // "key" and "mouse" are not mapped her, see GetPrimitiveValueType.
       return parameterType == "string" || parameterType == "layer" ||
              parameterType == "color" || parameterType == "file" ||
              parameterType == "stringWithSelector" ||
@@ -227,6 +230,26 @@ class GD_CORE_API ValueTypeMetadata {
     return false;
   }
 
+  /**
+   * \brief Return true if the type is a value of the given primitive type from
+   * the function events point of view
+   */
+  static bool IsTypeValue(const gd::String &type,
+                           const gd::String &parameterType) {
+    if (gd::ValueTypeMetadata::IsTypeExpression(type, parameterType)) {
+      return true;
+    }
+    // These 2 parameter types are not strings from the outside of a function as
+    // the generator add quote around a text, but from the events inside of the
+    // function the parameter is a string.
+    //
+    // See EventsCodeGenerator::GenerateParameterCodes
+    if (type == "string") {
+      return parameterType == "key" || parameterType == "mouse";
+    }
+    return false;
+  }
+
   /**
    * \brief Return the expression type from the parameter type.
    * Declinations of "number" and "string" types (like "forceMultiplier" or
@@ -278,9 +301,11 @@ class GD_CORE_API ValueTypeMetadata {
 
   static const gd::String numberValueType;
   static const gd::String booleanValueType;
+  static const gd::String stringValueType;
   static const gd::String colorValueType;
   static const gd::String choiceValueType;
-  static const gd::String stringValueType;
+  static const gd::String behaviorValueType;
+  static const gd::String leaderboardIdValueType;
 };
 
 }  // namespace gd

Core/GDCore/Extensions/PlatformExtension.h

@@ -40,8 +40,7 @@ class Object;
 class ObjectConfiguration;
 }  // namespace gd
 
-typedef std::function<std::unique_ptr<gd::ObjectConfiguration>()>
-    CreateFunPtr;
+typedef std::function<std::unique_ptr<gd::ObjectConfiguration>()> CreateFunPtr;
 
 namespace gd {
 
@@ -51,25 +50,25 @@ namespace gd {
  */
 class GD_CORE_API CompilationInfo {
  public:
-  CompilationInfo() : informationCompleted(false){};
-  virtual ~CompilationInfo(){};
+  CompilationInfo() {};
+  virtual ~CompilationInfo() {};
 
-  bool informationCompleted;
+  bool informationCompleted = false;
 
-  bool runtimeOnly;  ///< True if the extension was compiled for a runtime use
-                     ///< only
+  bool runtimeOnly = false;  ///< True if the extension was compiled for a
+                             ///< runtime use only
 
 #if defined(__GNUC__)
-  int gccMajorVersion;
-  int gccMinorVersion;
-  int gccPatchLevel;
+  int gccMajorVersion = 0;
+  int gccMinorVersion = 0;
+  int gccPatchLevel = 0;
 #endif
 
-  int sfmlMajorVersion;
-  int sfmlMinorVersion;
+  int sfmlMajorVersion = 0;
+  int sfmlMinorVersion = 0;
 
   gd::String gdCoreVersion;
-  int sizeOfpInt;
+  int sizeOfpInt = 0;
 };
 
 struct GD_CORE_API DuplicatedInstructionOptions {
@@ -239,11 +238,12 @@ class GD_CORE_API PlatformExtension {
    * \param instance The "blueprint" object to be copied when a new object is
    asked for.
    */
-  gd::ObjectMetadata& AddObject(const gd::String& name_,
-                                const gd::String& fullname_,
-                                const gd::String& description_,
-                                const gd::String& icon_,
-                                std::shared_ptr<gd::ObjectConfiguration> instance);
+  gd::ObjectMetadata& AddObject(
+      const gd::String& name_,
+      const gd::String& fullname_,
+      const gd::String& description_,
+      const gd::String& icon_,
+      std::shared_ptr<gd::ObjectConfiguration> instance);
 
   /**
    * \brief Declare a new events based object as being part of the extension.
@@ -253,11 +253,10 @@ class GD_CORE_API PlatformExtension {
    * \param description The user friendly description of the object
    * \param icon The icon of the object.
    */
-  gd::ObjectMetadata& AddEventsBasedObject(
-      const gd::String& name_,
-      const gd::String& fullname_,
-      const gd::String& description_,
-      const gd::String& icon_);
+  gd::ObjectMetadata& AddEventsBasedObject(const gd::String& name_,
+                                           const gd::String& fullname_,
+                                           const gd::String& description_,
+                                           const gd::String& icon_);
 
   /**
    * \brief Declare a new behavior as being part of the extension.
@@ -420,8 +419,7 @@ class GD_CORE_API PlatformExtension {
   PlatformExtension& SetTags(const gd::String& csvTags) {
     tags.clear();
     tags = csvTags.Split(',');
-    for (size_t i = 0; i < tags.size(); i++)
-    {
+    for (size_t i = 0; i < tags.size(); i++) {
       tags[i] = tags[i].Trim().LowerCase();
     }
     return *this;
@@ -634,31 +632,30 @@ class GD_CORE_API PlatformExtension {
    */
   static gd::String GetNamespaceSeparator() { return "::"; }
 
-  static gd::String GetEventsFunctionFullType(const gd::String &extensionName,
-                                              const gd::String &functionName);
+  static gd::String GetEventsFunctionFullType(const gd::String& extensionName,
+                                              const gd::String& functionName);
 
-  static gd::String
-  GetBehaviorEventsFunctionFullType(const gd::String &extensionName,
-                                    const gd::String &behaviorName,
-                                    const gd::String &functionName);
+  static gd::String GetBehaviorEventsFunctionFullType(
+      const gd::String& extensionName,
+      const gd::String& behaviorName,
+      const gd::String& functionName);
 
-  static gd::String GetBehaviorFullType(const gd::String &extensionName,
-                                        const gd::String &behaviorName);
+  static gd::String GetBehaviorFullType(const gd::String& extensionName,
+                                        const gd::String& behaviorName);
 
-  static gd::String
-  GetObjectEventsFunctionFullType(const gd::String &extensionName,
-                                  const gd::String &objectName,
-                                  const gd::String &functionName);
-
-  static gd::String GetObjectFullType(const gd::String &extensionName,
-                                      const gd::String &objectName);
+  static gd::String GetObjectEventsFunctionFullType(
+      const gd::String& extensionName,
+      const gd::String& objectName,
+      const gd::String& functionName);
 
+  static gd::String GetObjectFullType(const gd::String& extensionName,
+                                      const gd::String& objectName);
 
   static gd::String GetExtensionFromFullObjectType(const gd::String& type);
 
   static gd::String GetObjectNameFromFullObjectType(const gd::String& type);
 
-private:
+ private:
   /**
    * Set the namespace (the string all actions/conditions/expressions start
    * with).
@@ -673,10 +670,10 @@ private:
   gd::String fullname;      ///< Name displayed to users in the editor.
   gd::String informations;  ///< Description displayed to users in the editor.
   gd::String category;
-  gd::String author;        ///< Author displayed to users in the editor.
-  gd::String license;       ///< License name displayed to users in the editor.
-  bool deprecated;  ///< true if the extension is deprecated and shouldn't be
-                    ///< shown in IDE.
+  gd::String author;   ///< Author displayed to users in the editor.
+  gd::String license;  ///< License name displayed to users in the editor.
+  bool deprecated;     ///< true if the extension is deprecated and shouldn't be
+                       ///< shown in IDE.
   gd::String helpPath;  ///< The relative path to the help for this extension in
                         ///< the documentation.
   gd::String iconUrl;   ///< The URL to the icon to be shown for this extension.

Core/GDCore/Extensions/PlatformExtension.inl

@@ -5,6 +5,8 @@
  * project is released under the MIT License.
  */
 
+// NOLINTBEGIN
+
 #ifndef GDCORE_PLATFORMEXTENSION_INL
 #define GDCORE_PLATFORMEXTENSION_INL
 
@@ -36,3 +38,5 @@ gd::ObjectMetadata& PlatformExtension::AddObject(const gd::String& name,
 }  // namespace gd
 
 #endif
+
+// NOLINTEND

Core/GDCore/IDE/CaptureOptions.cpp

@@ -0,0 +1,18 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#include "GDCore/IDE/CaptureOptions.h"
+
+#include "GDCore/String.h"
+
+using namespace std;
+
+namespace gd {
+
+Screenshot::Screenshot() {}
+
+CaptureOptions::CaptureOptions() {}
+
+}  // namespace gd

Core/GDCore/IDE/CaptureOptions.h

@@ -0,0 +1,50 @@
+#pragma once
+#include <memory>
+#include <vector>
+
+#include "GDCore/String.h"
+
+namespace gd {
+
+class GD_CORE_API Screenshot {
+ public:
+  Screenshot();
+  virtual ~Screenshot() {};
+
+  void SetDelayTimeInSeconds(int delayTimeInMs_) {
+    delayTimeInMs = delayTimeInMs_;
+  }
+  int GetDelayTimeInSeconds() const { return delayTimeInMs; }
+
+  void SetSignedUrl(const gd::String& signedUrl_) { signedUrl = signedUrl_; }
+  const gd::String& GetSignedUrl() const { return signedUrl; }
+
+  void SetPublicUrl(const gd::String& publicUrl_) { publicUrl = publicUrl_; }
+  const gd::String& GetPublicUrl() const { return publicUrl; }
+
+ private:
+  int delayTimeInMs = 0;
+  gd::String signedUrl;
+  gd::String publicUrl;
+};
+
+class GD_CORE_API CaptureOptions {
+ public:
+  CaptureOptions();
+  virtual ~CaptureOptions() {};
+
+  bool IsEmpty() const { return screenshots.empty(); }
+
+  void AddScreenshot(const Screenshot& screenshot) {
+    screenshots.push_back(screenshot);
+  }
+
+  const std::vector<Screenshot>& GetScreenshots() const { return screenshots; }
+
+  void ClearScreenshots() { screenshots.clear(); }
+
+ private:
+  std::vector<Screenshot> screenshots;
+};
+
+}  // namespace gd

Core/GDCore/IDE/Events/EventsLeaderboardsLister.cpp

@@ -1,41 +0,0 @@
-/*
- * GDevelop Core
- * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
- * reserved. This project is released under the MIT License.
- */
-#include "GDCore/IDE/Events/EventsLeaderboardsLister.h"
-
-#include <map>
-#include <memory>
-#include <vector>
-
-#include "GDCore/Events/Event.h"
-#include "GDCore/Events/EventsList.h"
-#include "GDCore/Extensions/Metadata/InstructionMetadata.h"
-#include "GDCore/Extensions/Metadata/MetadataProvider.h"
-#include "GDCore/Project/Layout.h"
-#include "GDCore/Project/Project.h"
-#include "GDCore/String.h"
-
-namespace gd {
-
-bool EventsLeaderboardsLister::DoVisitInstruction(gd::Instruction& instruction,
-                                                  bool isCondition) {
-  const gd::InstructionMetadata& instrInfo =
-      isCondition ? MetadataProvider::GetConditionMetadata(
-                        project.GetCurrentPlatform(), instruction.GetType())
-                  : MetadataProvider::GetActionMetadata(
-                        project.GetCurrentPlatform(), instruction.GetType());
-
-  for (int i = 0; i < instruction.GetParametersCount() &&
-                  i < instrInfo.GetParametersCount();
-       ++i)
-    if (instrInfo.GetParameter(i).GetType() == "leaderboardId") {
-      leaderboardIds.insert(instruction.GetParameter(i).GetPlainString());
-    }
-  return false;
-}
-
-EventsLeaderboardsLister::~EventsLeaderboardsLister() {}
-
-}  // namespace gd

Core/GDCore/IDE/Events/EventsLeaderboardsLister.h

@@ -1,48 +0,0 @@
-/*
- * GDevelop Core
- * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
- * reserved. This project is released under the MIT License.
- */
-#ifndef EventsLeaderboardsLister_H
-#define EventsLeaderboardsLister_H
-#include <map>
-#include <memory>
-#include <set>
-#include <vector>
-
-#include "GDCore/IDE/Events/ArbitraryEventsWorker.h"
-#include "GDCore/String.h"
-namespace gd {
-class BaseEvent;
-class Project;
-class EventsList;
-}
-
-namespace gd {
-
-/**
- * \brief List the leaderboard ids in the instructions.
- *
- * \ingroup IDE
- */
-class GD_CORE_API EventsLeaderboardsLister : public ArbitraryEventsWorker {
- public:
-  EventsLeaderboardsLister(gd::Project& project_) : project(project_){};
-  virtual ~EventsLeaderboardsLister();
-
-  /**
-   * Return the values of all leaderboardIds found in the events.
-   */
-  const std::set<gd::String>& GetLeaderboardIds() { return leaderboardIds; }
-
- private:
-  virtual bool DoVisitInstruction(gd::Instruction& instruction,
-                                  bool isCondition);
-
-  std::set<gd::String> leaderboardIds;
-  gd::Project& project;
-};
-
-}  // namespace gd
-
-#endif  // EventsLeaderboardsLister_H

Core/GDCore/IDE/Events/EventsLeaderboardsRenamer.cpp

@@ -1,49 +0,0 @@
-/*
- * GDevelop Core
- * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
- * reserved. This project is released under the MIT License.
- */
-#include "GDCore/IDE/Events/EventsLeaderboardsRenamer.h"
-
-#include <map>
-#include <memory>
-#include <vector>
-
-#include "GDCore/Events/Event.h"
-#include "GDCore/Events/EventsList.h"
-#include "GDCore/Extensions/Metadata/InstructionMetadata.h"
-#include "GDCore/Extensions/Metadata/MetadataProvider.h"
-#include "GDCore/Project/Layout.h"
-#include "GDCore/Project/Project.h"
-#include "GDCore/String.h"
-
-namespace gd {
-
-bool EventsLeaderboardsRenamer::DoVisitInstruction(gd::Instruction& instruction,
-                                                   bool isCondition) {
-  const gd::InstructionMetadata& instrInfo =
-      isCondition ? MetadataProvider::GetConditionMetadata(
-                        project.GetCurrentPlatform(), instruction.GetType())
-                  : MetadataProvider::GetActionMetadata(
-                        project.GetCurrentPlatform(), instruction.GetType());
-
-  for (int i = 0; i < instruction.GetParametersCount() &&
-                  i < instrInfo.GetParametersCount();
-       ++i) {
-    const gd::ParameterMetadata parameter = instrInfo.GetParameter(i);
-
-    if (parameter.GetType() == "leaderboardId") {
-      const gd::String leaderboardId =
-          instruction.GetParameter(i).GetPlainString();
-
-      if (leaderboardIdMap.find(leaderboardId) != leaderboardIdMap.end()) {
-        instruction.SetParameter(i, leaderboardIdMap[leaderboardId]);
-      }
-    }
-  }
-  return false;
-}
-
-EventsLeaderboardsRenamer::~EventsLeaderboardsRenamer() {}
-
-}  // namespace gd

Core/GDCore/IDE/Events/EventsLeaderboardsRenamer.h

@@ -1,46 +0,0 @@
-/*
- * GDevelop Core
- * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
- * reserved. This project is released under the MIT License.
- */
-#ifndef EventsLeaderboardsRenamer_H
-#define EventsLeaderboardsRenamer_H
-#include <map>
-#include <memory>
-#include <set>
-#include <vector>
-
-#include "GDCore/IDE/Events/ArbitraryEventsWorker.h"
-#include "GDCore/String.h"
-namespace gd {
-class BaseEvent;
-class Project;
-class EventsList;
-}
-
-namespace gd {
-
-/**
- * \brief Replace the leaderboard ids in the instructions.
- *
- * \ingroup IDE
- */
-class GD_CORE_API EventsLeaderboardsRenamer : public ArbitraryEventsWorker {
- public:
-  EventsLeaderboardsRenamer(
-      gd::Project& project_,
-      const std::map<gd::String, gd::String>& leaderboardIdMap_)
-      : project(project_), leaderboardIdMap(leaderboardIdMap_){};
-  virtual ~EventsLeaderboardsRenamer();
-
- private:
-  virtual bool DoVisitInstruction(gd::Instruction& instruction,
-                                  bool isCondition);
-
-  std::map<gd::String, gd::String> leaderboardIdMap;
-  gd::Project& project;
-};
-
-}  // namespace gd
-
-#endif  // EventsLeaderboardsRenamer_H

Core/GDCore/IDE/Events/EventsPropertyReplacer.cpp

@@ -41,6 +41,7 @@ class GD_CORE_API ExpressionPropertyReplacer
       const gd::Platform& platform_,
       const gd::ProjectScopedContainers& projectScopedContainers_,
       const gd::PropertiesContainer& targetPropertiesContainer_,
+      bool isParentTypeAVariable_,
       const std::unordered_map<gd::String, gd::String>& oldToNewPropertyNames_,
       const std::unordered_set<gd::String>& removedPropertyNames_)
       : hasDoneRenaming(false),
@@ -48,6 +49,7 @@ class GD_CORE_API ExpressionPropertyReplacer
         platform(platform_),
         projectScopedContainers(projectScopedContainers_),
         targetPropertiesContainer(targetPropertiesContainer_),
+        isParentTypeAVariable(isParentTypeAVariable_),
         oldToNewPropertyNames(oldToNewPropertyNames_),
         removedPropertyNames(removedPropertyNames_){};
   virtual ~ExpressionPropertyReplacer(){};
@@ -69,16 +71,21 @@ class GD_CORE_API ExpressionPropertyReplacer
   void OnVisitNumberNode(NumberNode& node) override {}
   void OnVisitTextNode(TextNode& node) override {}
   void OnVisitVariableNode(VariableNode& node) override {
+    if (isParentTypeAVariable) {
+        // Do nothing, it's a variable.
+        if (node.child) node.child->Visit(*this);
+        return;
+    }
+
     auto& propertiesContainersList =
         projectScopedContainers.GetPropertiesContainersList();
 
     // The node represents a variable or an object name on which a variable
     // will be accessed, or a property with a child.
 
-    // Match the potential *new* name of the property, because refactorings are
-    // done after changes in the variables container.
     projectScopedContainers.MatchIdentifierWithName<void>(
-      GetPotentialNewName(node.name),
+      // The property name is changed after the refactor operation.
+      node.name,
       [&]() {
         // Do nothing, it's an object variable.
         if (node.child) node.child->Visit(*this);
@@ -100,16 +107,7 @@ class GD_CORE_API ExpressionPropertyReplacer
         // Do nothing, it's a parameter.
         if (node.child) node.child->Visit(*this);
       }, [&]() {
-        // This is something else - potentially a deleted property.
-        // Check if it's coming from the target container with
-        // properties to replace.
-        if (propertiesContainersList.HasPropertiesContainer(
-                targetPropertiesContainer)) {
-          // The node represents a property, that can come from the target
-          // (because the target is in the scope), replace or remove it:
-          RenameOrRemovePropertyOfTargetPropertyContainer(node.name);
-        }
-
+        // Do nothing, it's something else.
         if (node.child) node.child->Visit(*this);
       });
   }
@@ -118,17 +116,24 @@ class GD_CORE_API ExpressionPropertyReplacer
   }
   void OnVisitVariableBracketAccessorNode(
       VariableBracketAccessorNode& node) override {
+    bool isGrandParentTypeAVariable = isParentTypeAVariable;
+    isParentTypeAVariable = false;
     node.expression->Visit(*this);
+    isParentTypeAVariable = isGrandParentTypeAVariable;
     if (node.child) node.child->Visit(*this);
   }
   void OnVisitIdentifierNode(IdentifierNode& node) override {
+    if (isParentTypeAVariable) {
+        // Do nothing, it's a variable.
+        return;
+    }
+
     auto& propertiesContainersList =
         projectScopedContainers.GetPropertiesContainersList();
 
-    // Match the potential *new* name of the property, because refactorings are
-    // done after changes in the variables container.
     projectScopedContainers.MatchIdentifierWithName<void>(
-      GetPotentialNewName(node.identifierName),
+      // The property name is changed after the refactor operation
+      node.identifierName,
       [&]() {
         // Do nothing, it's an object variable.
       }, [&]() {
@@ -145,22 +150,29 @@ class GD_CORE_API ExpressionPropertyReplacer
       }, [&]() {
         // Do nothing, it's a parameter.
       }, [&]() {
-        // This is something else - potentially a deleted property.
-        // Check if it's coming from the target container with
-        // properties to replace.
-        if (propertiesContainersList.HasPropertiesContainer(
-                targetPropertiesContainer)) {
-          // The node represents a property, that can come from the target
-          // (because the target is in the scope), replace or remove it:
-          RenameOrRemovePropertyOfTargetPropertyContainer(node.identifierName);
-        }
+        // Do nothing, it's something else.
       });
   }
   void OnVisitObjectFunctionNameNode(ObjectFunctionNameNode& node) override {}
-  void OnVisitFunctionCallNode(FunctionCallNode& node) override {
-    for (auto& parameter : node.parameters) {
-      parameter->Visit(*this);
+  void OnVisitFunctionCallNode(FunctionCallNode &node) override {
+    bool isGrandParentTypeAVariable = isParentTypeAVariable;
+    for (auto &parameter : node.parameters) {
+      const auto &parameterMetadata =
+          gd::MetadataProvider::GetFunctionCallParameterMetadata(
+              platform, projectScopedContainers.GetObjectsContainersList(),
+              node, *parameter);
+      if (!parameterMetadata) {
+        continue;
+      }
+      const auto &parameterTypeMetadata =
+          parameterMetadata->GetValueTypeMetadata();
+      if (gd::EventsPropertyReplacer::CanContainProperty(
+              parameterTypeMetadata)) {
+        isParentTypeAVariable = parameterTypeMetadata.IsVariable();
+        parameter->Visit(*this);
+      }
     }
+    isParentTypeAVariable = isGrandParentTypeAVariable;
   }
   void OnVisitEmptyNode(EmptyNode& node) override {}
 
@@ -168,12 +180,6 @@ class GD_CORE_API ExpressionPropertyReplacer
   bool hasDoneRenaming;
   bool removedPropertyUsed;
 
-  const gd::String& GetPotentialNewName(const gd::String& oldName) {
-    return oldToNewPropertyNames.count(oldName) >= 1
-            ? oldToNewPropertyNames.find(oldName)->second
-            : oldName;
-  }
-
   bool RenameOrRemovePropertyOfTargetPropertyContainer(
       gd::String& propertyName) {
     if (oldToNewPropertyNames.count(propertyName) >= 1) {
@@ -198,6 +204,7 @@ class GD_CORE_API ExpressionPropertyReplacer
   const std::unordered_set<gd::String>& removedPropertyNames;
 
   gd::String objectNameToUseForVariableAccessor;
+  bool isParentTypeAVariable;
 };
 
 bool EventsPropertyReplacer::DoVisitInstruction(gd::Instruction& instruction,
@@ -216,20 +223,16 @@ bool EventsPropertyReplacer::DoVisitInstruction(gd::Instruction& instruction,
           const gd::Expression& parameterValue,
           size_t parameterIndex,
           const gd::String& lastObjectName) {
-        const gd::String& type = parameterMetadata.GetType();
-
-        if (!gd::ParameterMetadata::IsExpression("variable", type) &&
-            !gd::ParameterMetadata::IsExpression("number", type) &&
-            !gd::ParameterMetadata::IsExpression("string", type))
-          return;  // Not an expression that can contain properties.
-
+        if (!gd::EventsPropertyReplacer::CanContainProperty(
+          parameterMetadata.GetValueTypeMetadata())) {
+          return;
+        }
         auto node = parameterValue.GetRootNode();
         if (node) {
-          ExpressionPropertyReplacer renamer(platform,
-                                             GetProjectScopedContainers(),
-                                             targetPropertiesContainer,
-                                             oldToNewPropertyNames,
-                                             removedPropertyNames);
+          ExpressionPropertyReplacer renamer(
+              platform, GetProjectScopedContainers(), targetPropertiesContainer,
+              parameterMetadata.GetValueTypeMetadata().IsVariable(),
+              oldToNewPropertyNames, removedPropertyNames);
           node->Visit(renamer);
 
           if (renamer.IsRemovedPropertyUsed()) {
@@ -246,20 +249,16 @@ bool EventsPropertyReplacer::DoVisitInstruction(gd::Instruction& instruction,
 
 bool EventsPropertyReplacer::DoVisitEventExpression(
     gd::Expression& expression, const gd::ParameterMetadata& metadata) {
-  const gd::String& type = metadata.GetType();
-
-  if (!gd::ParameterMetadata::IsExpression("variable", type) &&
-      !gd::ParameterMetadata::IsExpression("number", type) &&
-      !gd::ParameterMetadata::IsExpression("string", type))
-    return false;  // Not an expression that can contain properties.
-
+  if (!gd::EventsPropertyReplacer::CanContainProperty(
+          metadata.GetValueTypeMetadata())) {
+    return false;
+  }
   auto node = expression.GetRootNode();
   if (node) {
-    ExpressionPropertyReplacer renamer(platform,
-                                       GetProjectScopedContainers(),
-                                       targetPropertiesContainer,
-                                       oldToNewPropertyNames,
-                                       removedPropertyNames);
+    ExpressionPropertyReplacer renamer(
+        platform, GetProjectScopedContainers(), targetPropertiesContainer,
+        metadata.GetValueTypeMetadata().IsVariable(), oldToNewPropertyNames,
+        removedPropertyNames);
     node->Visit(renamer);
 
     if (renamer.IsRemovedPropertyUsed()) {
@@ -272,6 +271,12 @@ bool EventsPropertyReplacer::DoVisitEventExpression(
   return false;
 }
 
+bool EventsPropertyReplacer::CanContainProperty(
+    const gd::ValueTypeMetadata &valueTypeMetadata) {
+  return valueTypeMetadata.IsVariable() || valueTypeMetadata.IsNumber() ||
+         valueTypeMetadata.IsString();
+}
+
 EventsPropertyReplacer::~EventsPropertyReplacer() {}
 
 }  // namespace gd

Core/GDCore/IDE/Events/EventsPropertyReplacer.h

@@ -41,6 +41,8 @@ class GD_CORE_API EventsPropertyReplacer
         removedPropertyNames(removedPropertyNames_){};
   virtual ~EventsPropertyReplacer();
 
+  static bool CanContainProperty(const gd::ValueTypeMetadata &valueTypeMetadata);
+
  private:
   bool DoVisitInstruction(gd::Instruction &instruction,
                           bool isCondition) override;

Core/GDCore/IDE/Events/ExpressionCompletionFinder.h

@@ -337,19 +337,19 @@ struct GD_CORE_API ExpressionCompletionDescription {
 
  private:
   CompletionKind completionKind;
-  gd::Variable::Type variableType;
-  gd::VariablesContainer::SourceType variableScope;
+  gd::Variable::Type variableType = gd::Variable::Unknown;
+  gd::VariablesContainer::SourceType variableScope = gd::VariablesContainer::Unknown;
   gd::String type;
   gd::String prefix;
   gd::String completion;
-  size_t replacementStartPosition;
-  size_t replacementEndPosition;
+  size_t replacementStartPosition = 0;
+  size_t replacementEndPosition = 0;
   gd::String objectName;
   gd::String behaviorName;
-  bool isExact;
-  bool isLastParameter;
-  const gd::ParameterMetadata* parameterMetadata;
-  const gd::ObjectConfiguration* objectConfiguration;
+  bool isExact = false;
+  bool isLastParameter = false;
+  const gd::ParameterMetadata* parameterMetadata = &badParameterMetadata;
+  const gd::ObjectConfiguration* objectConfiguration = &badObjectConfiguration;
 
   static const gd::ParameterMetadata badParameterMetadata;
   static const gd::ObjectConfiguration badObjectConfiguration;
@@ -1066,8 +1066,8 @@ class GD_CORE_API ExpressionCompletionFinder
       bool eagerlyCompleteIfExactMatch = false) {
     projectScopedContainers.ForEachIdentifierMatchingSearch(
         search,
-        [&](const gd::String& objectName,
-            const ObjectConfiguration* objectConfiguration) {
+        [&](const gd::String &objectName,
+            const ObjectConfiguration *objectConfiguration) {
           ExpressionCompletionDescription description(
               ExpressionCompletionDescription::Object,
               location.GetStartPosition(),
@@ -1077,7 +1077,7 @@ class GD_CORE_API ExpressionCompletionFinder
           description.SetType(type);
           completions.push_back(description);
         },
-        [&](const gd::String& variableName, const gd::Variable& variable) {
+        [&](const gd::String &variableName, const gd::Variable &variable) {
           ExpressionCompletionDescription description(
               ExpressionCompletionDescription::Variable,
               location.GetStartPosition(),
@@ -1095,23 +1095,29 @@ class GD_CORE_API ExpressionCompletionFinder
                 variable, variableName, location);
           }
         },
-        [&](const gd::NamedPropertyDescriptor& property) {
-          ExpressionCompletionDescription description(
-              ExpressionCompletionDescription::Property,
-              location.GetStartPosition(),
-              location.GetEndPosition());
-          description.SetCompletion(property.GetName());
-          description.SetType(property.GetType());
-          completions.push_back(description);
+        [&](const gd::NamedPropertyDescriptor &property) {
+          auto propertyType = gd::ValueTypeMetadata::ConvertPropertyTypeToValueType(
+              property.GetType());
+          if (gd::ValueTypeMetadata::IsTypeValue("number", propertyType) ||
+              gd::ValueTypeMetadata::IsTypeValue("string", propertyType)) {
+            ExpressionCompletionDescription description(
+                ExpressionCompletionDescription::Property,
+                location.GetStartPosition(), location.GetEndPosition());
+            description.SetCompletion(property.GetName());
+            description.SetType(property.GetType());
+            completions.push_back(description);
+          }
         },
-        [&](const gd::ParameterMetadata& parameter) {
-          ExpressionCompletionDescription description(
-              ExpressionCompletionDescription::Parameter,
-              location.GetStartPosition(),
-              location.GetEndPosition());
-          description.SetCompletion(parameter.GetName());
-          description.SetType(parameter.GetType());
-          completions.push_back(description);
+        [&](const gd::ParameterMetadata &parameter) {
+          if (parameter.GetValueTypeMetadata().IsNumber() ||
+              parameter.GetValueTypeMetadata().IsString()) {
+            ExpressionCompletionDescription description(
+                ExpressionCompletionDescription::Parameter,
+                location.GetStartPosition(), location.GetEndPosition());
+            description.SetCompletion(parameter.GetName());
+            description.SetType(parameter.GetType());
+            completions.push_back(description);
+          }
         });
   }
 

Core/GDCore/IDE/Events/ExpressionNodeLocationFinder.h

@@ -33,8 +33,10 @@ class GD_CORE_API ExpressionNodeLocationFinder
    * \brief Initialize the finder to search at the specified position.
    */
   ExpressionNodeLocationFinder(size_t searchedPosition_)
-      : searchedPosition(searchedPosition_), foundNode(nullptr){};
-  virtual ~ExpressionNodeLocationFinder(){};
+      : searchedPosition(searchedPosition_),
+        foundNode(nullptr),
+        parentNode(nullptr) {};
+  virtual ~ExpressionNodeLocationFinder() {};
 
   /**
    * \brief Helper function to find the deepest node at the search position, if

Core/GDCore/IDE/Events/ExpressionTypeFinder.h

@@ -72,7 +72,7 @@ class GD_CORE_API ExpressionTypeFinder : public ExpressionParser2NodeWorker {
         child(nullptr) {};
 
   const gd::String &GetType() {
-    return gd::ParameterMetadata::GetExpressionValueType(type);
+    return gd::ValueTypeMetadata::GetExpressionPrimitiveValueType(type);
   };
 
   void OnVisitSubExpressionNode(SubExpressionNode& node) override {

Core/GDCore/IDE/Events/ExpressionValidator.cpp

@@ -68,19 +68,26 @@ size_t GetMaximumParametersNumber(
 
 bool ExpressionValidator::ValidateObjectVariableOrVariableOrProperty(
     const gd::IdentifierNode& identifier) {
+  return ValidateObjectVariableOrVariableOrProperty(identifier.identifierName, identifier.identifierNameLocation, identifier.childIdentifierName, identifier.childIdentifierNameLocation);
+}
+
+bool ExpressionValidator::ValidateObjectVariableOrVariableOrProperty(
+    const gd::String &identifierName,
+    const gd::ExpressionParserLocation identifierNameLocation,
+    const gd::String &childIdentifierName,
+    const gd::ExpressionParserLocation childIdentifierNameLocation) {
   auto validateVariableTypeForExpression =
-      [this, &identifier](gd::Variable::Type type) {
+      [this, &identifierNameLocation](gd::Variable::Type type) {
         // Collections type can't be used directly in expressions, a child
         // must be accessed.
         if (type == Variable::Structure) {
           RaiseTypeError(_("You need to specify the name of the child variable "
                            "to access. For example: `MyVariable.child`."),
-                         identifier.identifierNameLocation);
+                         identifierNameLocation);
         } else if (type == Variable::Array) {
           RaiseTypeError(_("You need to specify the name of the child variable "
                            "to access. For example: `MyVariable[0]`."),
-                         identifier.identifierNameLocation);
-
+                         identifierNameLocation);
         } else {
           // Number, string or boolean variables can be used in expressions.
           return;
@@ -96,38 +103,41 @@ bool ExpressionValidator::ValidateObjectVariableOrVariableOrProperty(
   // we consider this node will be of the type required by the parent.
   childType = parentType;
 
-  return projectScopedContainers.MatchIdentifierWithName<bool>(identifier.identifierName,
+  return projectScopedContainers.MatchIdentifierWithName<bool>(identifierName,
     [&]() {
       // This represents an object.
-      if (identifier.childIdentifierName.empty()) {
+      if (childIdentifierName.empty()) {
         RaiseTypeError(_("An object variable or expression should be entered."),
-                        identifier.identifierNameLocation);
+                        identifierNameLocation);
 
         return true; // We should have found a variable.
       }
 
-      auto variableExistence = objectsContainersList.HasObjectOrGroupWithVariableNamed(identifier.identifierName, identifier.childIdentifierName);
+      auto variableExistence =
+          objectsContainersList.HasObjectOrGroupWithVariableNamed(
+              identifierName, childIdentifierName);
 
       if (variableExistence == gd::ObjectsContainersList::DoesNotExist) {
         RaiseUndeclaredVariableError(_("This variable does not exist on this object or group."),
-                        identifier.childIdentifierNameLocation, identifier.childIdentifierName, identifier.identifierName);
+                        childIdentifierNameLocation, childIdentifierName, identifierName);
 
         return true; // We should have found a variable.
       }
       else if (variableExistence == gd::ObjectsContainersList::ExistsOnlyOnSomeObjectsOfTheGroup) {
         RaiseUndeclaredVariableError(_("This variable only exists on some objects of the group. It must be declared for all objects."),
-                        identifier.childIdentifierNameLocation, identifier.childIdentifierName, identifier.identifierName);
+                        childIdentifierNameLocation, childIdentifierName, identifierName);
 
         return true; // We should have found a variable.
       }
       else if (variableExistence == gd::ObjectsContainersList::GroupIsEmpty) {
         RaiseUndeclaredVariableError(_("This group is empty. Add an object to this group first."),
-                        identifier.identifierNameLocation, identifier.childIdentifierName, identifier.identifierName);
+                        identifierNameLocation, childIdentifierName, identifierName);
 
         return true; // We should have found a variable.
       }
 
-      auto variableType = objectsContainersList.GetTypeOfObjectOrGroupVariable(identifier.identifierName, identifier.childIdentifierName);
+      auto variableType = objectsContainersList.GetTypeOfObjectOrGroupVariable(
+          identifierName, childIdentifierName);
       ReadChildTypeFromVariable(variableType);
 
       return true; // We found a variable.
@@ -137,9 +147,9 @@ bool ExpressionValidator::ValidateObjectVariableOrVariableOrProperty(
       // Try to identify a declared variable with the name (and maybe the child
       // variable).
       const gd::Variable& variable =
-          variablesContainersList.Get(identifier.identifierName);
+          variablesContainersList.Get(identifierName);
 
-      if (identifier.childIdentifierName.empty()) {
+      if (childIdentifierName.empty()) {
         // Just the root variable is accessed, check it can be used in an
         // expression.
         validateVariableTypeForExpression(variable.GetType());
@@ -148,33 +158,38 @@ bool ExpressionValidator::ValidateObjectVariableOrVariableOrProperty(
         return true; // We found a variable.
       } else {
         // A child variable is accessed, check it can be used in an expression.
-        if (!variable.HasChild(identifier.childIdentifierName)) {
+        if (!variable.HasChild(childIdentifierName)) {
           RaiseTypeError(_("No child variable with this name found."),
-                        identifier.childIdentifierNameLocation);
+                        childIdentifierNameLocation);
 
           return true; // We should have found a variable.
         }
 
         const gd::Variable& childVariable =
-            variable.GetChild(identifier.childIdentifierName);
+            variable.GetChild(childIdentifierName);
         ReadChildTypeFromVariable(childVariable.GetType());
         return true; // We found a variable.
       }
     }, [&]() {
       // This is a property.
-      if (!identifier.childIdentifierName.empty()) {
+      if (!childIdentifierName.empty()) {
         RaiseTypeError(_("Accessing a child variable of a property is not possible - just write the property name."),
-            identifier.childIdentifierNameLocation);
+            childIdentifierNameLocation);
 
         return true; // We found a property, even if the child is not allowed.
       }
 
-      const gd::NamedPropertyDescriptor& property = propertiesContainersList.Get(identifier.identifierName).second;
+      const gd::NamedPropertyDescriptor &property =
+          propertiesContainersList.Get(identifierName).second;
 
       if (property.GetType() == "Number") {
-       childType = Type::Number;
+        childType = Type::Number;
       } else if (property.GetType() == "Boolean") {
-        // Nothing - we don't know the precise type (this could be used a string or as a number)
+        // Nothing - we don't know the precise type (this could be used a string
+        // or as a number)
+      } else if (property.GetType() == "Behavior") {
+        RaiseTypeError(_("Behaviors can't be used as a value in expressions."),
+                       identifierNameLocation);
       } else {
         // Assume type is String or equivalent.
         childType = Type::String;
@@ -183,14 +198,14 @@ bool ExpressionValidator::ValidateObjectVariableOrVariableOrProperty(
       return true; // We found a property.
     }, [&]() {
       // This is a parameter.
-      if (!identifier.childIdentifierName.empty()) {
+      if (!childIdentifierName.empty()) {
         RaiseTypeError(_("Accessing a child variable of a parameter is not possible - just write the parameter name."),
-            identifier.childIdentifierNameLocation);
+            childIdentifierNameLocation);
 
         return true; // We found a parameter, even if the child is not allowed.
       }
 
-      const auto& parameter = gd::ParameterMetadataTools::Get(parametersVectorsList, identifier.identifierName);
+      const auto& parameter = gd::ParameterMetadataTools::Get(parametersVectorsList, identifierName);
       const auto& valueTypeMetadata = parameter.GetValueTypeMetadata();
       if (valueTypeMetadata.IsNumber()) {
         childType = Type::Number;
@@ -200,7 +215,7 @@ bool ExpressionValidator::ValidateObjectVariableOrVariableOrProperty(
         // Nothing - we don't know the precise type (this could be used as a string or as a number).
       } else {
         RaiseTypeError(_("This parameter is not a string, number or boolean - it can't be used in an expression."),
-            identifier.identifierNameLocation);
+            identifierNameLocation);
 
         return true; // We found a parameter, even though the type is incompatible.
       }

Core/GDCore/IDE/Events/ExpressionValidator.h

@@ -14,6 +14,7 @@
 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
 #include "GDCore/Project/ProjectScopedContainers.h"
 #include "GDCore/Project/VariablesContainersList.h"
+#include "GDCore/Project/VariablesContainer.h"
 
 namespace gd {
 class Expression;
@@ -42,10 +43,12 @@ class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
                       const gd::String &extraInfo_ = "")
       : platform(platform_),
         projectScopedContainers(projectScopedContainers_),
-        parentType(StringToType(gd::ParameterMetadata::GetExpressionValueType(rootType_))),
+        parentType(StringToType(gd::ValueTypeMetadata::GetExpressionPrimitiveValueType(rootType_))),
         childType(Type::Unknown),
         forbidsUsageOfBracketsBecauseParentIsObject(false),
-        currentParameterExtraInfo(&extraInfo_) {};
+        currentParameterExtraInfo(&extraInfo_),
+        variableObjectName(),
+        variableObjectNameLocation() {};
   virtual ~ExpressionValidator(){};
 
   /**
@@ -225,7 +228,8 @@ class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
       projectScopedContainers.MatchIdentifierWithName<void>(node.name,
         [&]() {
           // This represents an object.
-
+          variableObjectName = node.name;
+          variableObjectNameLocation = node.nameLocation;
           // While understood by the parser, it's forbidden to use the bracket notation just after
           // an object name (`MyObject["MyVariable"]`).
           forbidsUsageOfBracketsBecauseParentIsObject = true;
@@ -264,7 +268,13 @@ class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
   }
   void OnVisitVariableAccessorNode(VariableAccessorNode& node) override {
     ReportAnyError(node);
-
+    // TODO Also check child-variables existence on a path with only VariableAccessor to raise non-fatal errors.
+    if (!variableObjectName.empty()) {
+      ValidateObjectVariableOrVariableOrProperty(variableObjectName,
+                                                 variableObjectNameLocation,
+                                                 node.name, node.nameLocation);
+      variableObjectName = "";
+    }
     // In the case we accessed an object variable (`MyObject.MyVariable`),
     // brackets can now be used (`MyObject.MyVariable["MyChildVariable"]` is now valid).
     forbidsUsageOfBracketsBecauseParentIsObject = false;
@@ -277,6 +287,7 @@ class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
       VariableBracketAccessorNode& node) override {
     ReportAnyError(node);
 
+    variableObjectName = "";
     if (forbidsUsageOfBracketsBecauseParentIsObject) {
       RaiseError(gd::ExpressionParserError::ErrorType::BracketsNotAllowedForObjects,
                  _("You can't use the brackets to access an object variable. "
@@ -369,6 +380,11 @@ class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
   enum Type {Unknown = 0, Number, String, NumberOrString, Variable, LegacyVariable, Object, Empty};
   Type ValidateFunction(const gd::FunctionCallNode& function);
   bool ValidateObjectVariableOrVariableOrProperty(const gd::IdentifierNode& identifier);
+  bool ValidateObjectVariableOrVariableOrProperty(
+      const gd::String &identifierName,
+      const gd::ExpressionParserLocation identifierNameLocation,
+      const gd::String &childIdentifierName,
+      const gd::ExpressionParserLocation childIdentifierNameLocation);
 
   void CheckVariableExistence(const ExpressionParserLocation &location, const gd::String& name) {
     if (!currentParameterExtraInfo || *currentParameterExtraInfo != "AllowUndeclaredVariable") {
@@ -505,6 +521,8 @@ class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
   Type childType; ///< The type "discovered" down the tree and passed up.
   Type parentType; ///< The type "required" by the top of the tree.
   bool forbidsUsageOfBracketsBecauseParentIsObject;
+  gd::String variableObjectName;
+  gd::ExpressionParserLocation variableObjectNameLocation;
   const gd::String *currentParameterExtraInfo;
   const gd::Platform &platform;
   const gd::ProjectScopedContainers &projectScopedContainers;

Core/GDCore/IDE/Events/ExpressionsParameterMover.h

@@ -74,8 +74,8 @@ class GD_CORE_API ExpressionsParameterMover
 
   const gd::Platform &platform;
   gd::String functionName;
-  std::size_t oldIndex;
-  std::size_t newIndex;
+  std::size_t oldIndex = 0;
+  std::size_t newIndex = 0;
   gd::String behaviorType;
   gd::String objectType;
 };

Core/GDCore/IDE/Events/LeaderboardIdRenamer.cpp

@@ -0,0 +1,76 @@
+#include "LeaderboardIdRenamer.h"
+
+#include <map>
+#include <memory>
+#include <vector>
+
+#include "GDCore/Events/Event.h"
+#include "GDCore/Events/EventsList.h"
+#include "GDCore/Extensions/Metadata/InstructionMetadata.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Project/Behavior.h"
+#include "GDCore/Project/Layout.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Project/Project.h"
+#include "GDCore/Project/PropertyDescriptor.h"
+#include "GDCore/String.h"
+
+namespace gd {
+
+void LeaderboardIdRenamer::DoVisitObject(gd::Object &object) {
+  for (auto &pair : object.GetConfiguration().GetProperties()) {
+    auto &propertyName = pair.first;
+    auto &property = pair.second;
+    if (property.GetType() == "LeaderboardId") {
+      auto &leaderboardId = property.GetValue();
+
+      allLeaderboardIds.insert(leaderboardId);
+
+      if (leaderboardIdMap.find(leaderboardId) != leaderboardIdMap.end()) {
+        object.GetConfiguration().UpdateProperty(
+            propertyName, leaderboardIdMap[leaderboardId]);
+      }
+    }
+  }
+};
+
+void LeaderboardIdRenamer::DoVisitBehavior(gd::Behavior &behavior) {};
+
+bool LeaderboardIdRenamer::DoVisitInstruction(gd::Instruction &instruction,
+                                              bool isCondition) {
+  const gd::InstructionMetadata &instrInfo =
+      isCondition ? MetadataProvider::GetConditionMetadata(
+                        project.GetCurrentPlatform(), instruction.GetType())
+                  : MetadataProvider::GetActionMetadata(
+                        project.GetCurrentPlatform(), instruction.GetType());
+
+  for (int i = 0; i < instruction.GetParametersCount() &&
+                  i < instrInfo.GetParametersCount();
+       ++i) {
+    const gd::ParameterMetadata parameter = instrInfo.GetParameter(i);
+
+    if (parameter.GetType() != "leaderboardId") {
+      continue;
+    }
+    const gd::String leaderboardIdExpression =
+        instruction.GetParameter(i).GetPlainString();
+    if (leaderboardIdExpression[0] != '"' ||
+        leaderboardIdExpression[leaderboardIdExpression.size() - 1] != '"') {
+      continue;
+    }
+    const gd::String leaderboardId =
+        leaderboardIdExpression.substr(1, leaderboardIdExpression.size() - 2);
+
+    allLeaderboardIds.insert(leaderboardId);
+
+    if (leaderboardIdMap.find(leaderboardId) != leaderboardIdMap.end()) {
+      instruction.SetParameter(i,
+                               "\"" + leaderboardIdMap[leaderboardId] + "\"");
+    }
+  }
+  return false;
+}
+
+LeaderboardIdRenamer::~LeaderboardIdRenamer() {}
+
+}  // namespace gd

Core/GDCore/IDE/Events/LeaderboardIdRenamer.h

@@ -0,0 +1,50 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+
+#pragma once
+#include <map>
+
+#include "GDCore/IDE/Project/ArbitraryObjectsWorker.h"
+#include "GDCore/IDE/Events/ArbitraryEventsWorker.h"
+#include "GDCore/String.h"
+
+namespace gd {
+class Object;
+class Behavior;
+}  // namespace gd
+
+namespace gd {
+
+class GD_CORE_API LeaderboardIdRenamer : public ArbitraryObjectsWorker, public ArbitraryEventsWorker {
+ public:
+  LeaderboardIdRenamer(gd::Project& project_): project(project_) {};
+  virtual ~LeaderboardIdRenamer();
+
+  /**
+   * Set the leaderboard identifiers to be replaced.
+   */
+  void SetLeaderboardIdsToReplace(const std::map<gd::String, gd::String>& leaderboardIdMap_) {
+    leaderboardIdMap = leaderboardIdMap_;
+  }
+
+  /**
+   * Return the all the leaderboard identifiers found in the project.
+   */
+  const std::set<gd::String>& GetAllLeaderboardIds() const {
+    return allLeaderboardIds;
+  }
+
+ private:
+  bool DoVisitInstruction(gd::Instruction& instruction, bool isCondition) override;
+  void DoVisitObject(gd::Object& object) override;
+  void DoVisitBehavior(gd::Behavior& behavior) override;
+
+  std::map<gd::String, gd::String> leaderboardIdMap;
+  std::set<gd::String> allLeaderboardIds;
+  gd::Project& project;
+};
+
+};  // namespace gd

Core/GDCore/IDE/EventsFunctionTools.cpp

@@ -24,15 +24,16 @@ void EventsFunctionTools::FreeEventsFunctionToObjectsContainer(
     const gd::EventsFunction& eventsFunction,
     gd::ObjectsContainer& outputObjectsContainer) {
   // Functions scope for objects is defined according
-  // to parameters
-  outputObjectsContainer.GetObjects().clear();
-  outputObjectsContainer.GetObjectGroups().Clear();
-
+  // to parameters.
   auto &parameters = eventsFunction.GetParametersForEvents(functionContainer);
   gd::ParameterMetadataTools::ParametersToObjectsContainer(
       project,
       parameters,
       outputObjectsContainer);
+
+  // TODO: in theory we should ensure stability of the groups across calls
+  // to this function. BUT groups in functions should probably have never been
+  // supported, so we're phasing this out in the UI.
   outputObjectsContainer.GetObjectGroups() = eventsFunction.GetObjectGroups();
 }
 
@@ -97,26 +98,6 @@ void EventsFunctionTools::ObjectEventsFunctionToObjectsContainer(
                   "for the parent. ");
     return;
   }
-
-  gd::EventsFunctionTools::CopyEventsBasedObjectChildrenToObjectsContainer(
-      eventsBasedObject, outputObjectsContainer);
-}
-
-void EventsFunctionTools::CopyEventsBasedObjectChildrenToObjectsContainer(
-    const gd::EventsBasedObject& eventsBasedObject,
-    gd::ObjectsContainer& outputObjectsContainer) {
-  auto &children = eventsBasedObject.GetObjects().GetObjects();
-  for (auto &childObject : children) {
-    auto child = childObject.get();
-    outputObjectsContainer.InsertObject(
-        *child, outputObjectsContainer.GetObjectsCount());
-  }
-  auto &childrenGroups = eventsBasedObject.GetObjects().GetObjectGroups();
-  for (size_t index = 0; index < childrenGroups.Count(); ++index) {
-    auto &childGroup = childrenGroups.Get(index);
-    outputObjectsContainer.GetObjectGroups().Insert(
-        childGroup, outputObjectsContainer.GetObjectGroups().Count());
-  }
 }
 
 }  // namespace gd

Core/GDCore/IDE/EventsFunctionTools.h

@@ -68,9 +68,5 @@ class GD_CORE_API EventsFunctionTools {
       const gd::EventsBasedObject& eventsBasedObject,
       const gd::EventsFunction& eventsFunction,
       gd::ObjectsContainer& outputObjectsContainer);
-
-  static void CopyEventsBasedObjectChildrenToObjectsContainer(
-      const gd::EventsBasedObject &eventsBasedObject,
-      gd::ObjectsContainer &outputObjectsContainer);
 };
 }  // namespace gd

Core/GDCore/IDE/ExportedDependencyResolver.h

@@ -4,6 +4,7 @@
 #include "GDCore/Extensions/Metadata/DependencyMetadata.h"
 #include "GDCore/Extensions/PlatformExtension.h"
 #include "GDCore/Project/Project.h"
+#include "GDCore/Extensions/Platform.h"
 
 namespace gd {
 

Core/GDCore/IDE/Project/ArbitraryResourceWorker.cpp

@@ -293,7 +293,7 @@ void ResourceWorkerInObjectsWorker::DoVisitObject(gd::Object &object) {
 };
 
 void ResourceWorkerInObjectsWorker::DoVisitBehavior(gd::Behavior &behavior){
-    // TODO Allow behaviors to expose resources
+  behavior.ExposeResources(worker);
 };
 
 gd::ResourceWorkerInObjectsWorker

Core/GDCore/IDE/ProjectBrowserHelper.cpp

@@ -170,7 +170,8 @@ void ProjectBrowserHelper::ExposeEventsFunctionsExtensionEvents(
     gd::ArbitraryEventsWorkerWithContext &worker) {
     // Add (free) events functions
     for (auto &&eventsFunction : eventsFunctionsExtension.GetInternalVector()) {
-      gd::ObjectsContainer parameterObjectsContainer;
+      gd::ObjectsContainer parameterObjectsContainer(
+          gd::ObjectsContainer::SourceType::Function);
       auto projectScopedContainers = gd::ProjectScopedContainers::
           MakeNewProjectScopedContainersForFreeEventsFunction(
               project, eventsFunctionsExtension, *eventsFunction,
@@ -209,7 +210,8 @@ void ProjectBrowserHelper::ExposeEventsBasedBehaviorEvents(
   auto &behaviorEventsFunctions = eventsBasedBehavior.GetEventsFunctions();
   for (auto &&eventsFunction : behaviorEventsFunctions.GetInternalVector()) {
 
-    gd::ObjectsContainer parameterObjectsContainers;
+    gd::ObjectsContainer parameterObjectsContainers(
+        gd::ObjectsContainer::SourceType::Function);
     auto projectScopedContainers = gd::ProjectScopedContainers::
         MakeNewProjectScopedContainersForBehaviorEventsFunction(
             project, eventsFunctionsExtension, eventsBasedBehavior,
@@ -236,7 +238,8 @@ void ProjectBrowserHelper::ExposeEventsBasedObjectEvents(
   auto &objectEventsFunctions = eventsBasedObject.GetEventsFunctions();
   for (auto &&eventsFunction : objectEventsFunctions.GetInternalVector()) {
 
-    gd::ObjectsContainer parameterObjectsContainers;
+    gd::ObjectsContainer parameterObjectsContainers(
+        gd::ObjectsContainer::SourceType::Function);
     auto projectScopedContainers = gd::ProjectScopedContainers::
         MakeNewProjectScopedContainersForObjectEventsFunction(
             project, eventsFunctionsExtension, eventsBasedObject,

Core/GDCore/IDE/PropertyFunctionGenerator.cpp

@@ -247,7 +247,7 @@ bool PropertyFunctionGenerator::CanGenerateGetterAndSetter(
     const gd::NamedPropertyDescriptor &property) {
   auto &type = property.GetType();
   if (type != "Boolean" && type != "Number" && type != "String" &&
-      type != "Choice" && type != "Color") {
+      type != "Choice" && type != "Color" && type != "LeaderboardId") {
     return false;
   }
 

Core/GDCore/IDE/WholeProjectRefactorer.cpp

@@ -28,6 +28,7 @@
 #include "GDCore/IDE/Events/InstructionsParameterMover.h"
 #include "GDCore/IDE/Events/InstructionsTypeRenamer.h"
 #include "GDCore/IDE/Events/LinkEventTargetRenamer.h"
+#include "GDCore/IDE/Events/LeaderboardIdRenamer.h"
 #include "GDCore/IDE/Events/ProjectElementRenamer.h"
 #include "GDCore/IDE/Project/BehaviorObjectTypeRenamer.h"
 #include "GDCore/IDE/Project/BehaviorsSharedDataBehaviorTypeRenamer.h"
@@ -949,6 +950,8 @@ void WholeProjectRefactorer::RenameEventsBasedBehaviorProperty(
     // Order is important: we first rename the expressions then the
     // instructions, to avoid being unable to fetch the metadata (the types of
     // parameters) of instructions after they are renamed.
+
+    // Rename legacy expressions like: Object.Behavior::PropertyMyPropertyName()
     gd::ExpressionsRenamer expressionRenamer =
         gd::ExpressionsRenamer(project.GetCurrentPlatform());
     expressionRenamer.SetReplacedBehaviorExpression(
@@ -958,14 +961,16 @@ void WholeProjectRefactorer::RenameEventsBasedBehaviorProperty(
         EventsBasedBehavior::GetPropertyExpressionName(newPropertyName));
     gd::ProjectBrowserHelper::ExposeProjectEvents(project, expressionRenamer);
 
+    // Rename property names directly used as an identifier.
     std::unordered_map<gd::String, gd::String> oldToNewPropertyNames = {
         {oldPropertyName, newPropertyName}};
     std::unordered_set<gd::String> removedPropertyNames;
     gd::EventsPropertyReplacer eventsPropertyReplacer(
         project.GetCurrentPlatform(), properties, oldToNewPropertyNames,
         removedPropertyNames);
-    gd::ProjectBrowserHelper::ExposeProjectEvents(project,
-                                                  eventsPropertyReplacer);
+    gd::ProjectBrowserHelper::ExposeEventsBasedBehaviorEvents(
+        project, eventsFunctionsExtension, eventsBasedBehavior,
+        eventsPropertyReplacer);
 
     gd::InstructionsTypeRenamer actionRenamer = gd::InstructionsTypeRenamer(
         project,
@@ -1020,6 +1025,8 @@ void WholeProjectRefactorer::RenameEventsBasedBehaviorSharedProperty(
     // Order is important: we first rename the expressions then the
     // instructions, to avoid being unable to fetch the metadata (the types of
     // parameters) of instructions after they are renamed.
+
+    // Rename legacy expressions like: Object.Behavior::SharedPropertyMyPropertyName()
     gd::ExpressionsRenamer expressionRenamer =
         gd::ExpressionsRenamer(project.GetCurrentPlatform());
     expressionRenamer.SetReplacedBehaviorExpression(
@@ -1029,14 +1036,16 @@ void WholeProjectRefactorer::RenameEventsBasedBehaviorSharedProperty(
         EventsBasedBehavior::GetSharedPropertyExpressionName(newPropertyName));
     gd::ProjectBrowserHelper::ExposeProjectEvents(project, expressionRenamer);
 
+    // Rename property names directly used as an identifier.
     std::unordered_map<gd::String, gd::String> oldToNewPropertyNames = {
         {oldPropertyName, newPropertyName}};
     std::unordered_set<gd::String> removedPropertyNames;
     gd::EventsPropertyReplacer eventsPropertyReplacer(
         project.GetCurrentPlatform(), properties, oldToNewPropertyNames,
         removedPropertyNames);
-    gd::ProjectBrowserHelper::ExposeProjectEvents(project,
-                                                  eventsPropertyReplacer);
+    gd::ProjectBrowserHelper::ExposeEventsBasedBehaviorEvents(
+        project, eventsFunctionsExtension, eventsBasedBehavior,
+        eventsPropertyReplacer);
 
     gd::InstructionsTypeRenamer actionRenamer = gd::InstructionsTypeRenamer(
         project,
@@ -1077,6 +1086,8 @@ void WholeProjectRefactorer::RenameEventsBasedObjectProperty(
   // Order is important: we first rename the expressions then the
   // instructions, to avoid being unable to fetch the metadata (the types of
   // parameters) of instructions after they are renamed.
+
+  // Rename legacy expressions like: Object.PropertyMyPropertyName()
   gd::ExpressionsRenamer expressionRenamer =
       gd::ExpressionsRenamer(project.GetCurrentPlatform());
   expressionRenamer.SetReplacedObjectExpression(
@@ -1086,14 +1097,16 @@ void WholeProjectRefactorer::RenameEventsBasedObjectProperty(
       EventsBasedObject::GetPropertyExpressionName(newPropertyName));
   gd::ProjectBrowserHelper::ExposeProjectEvents(project, expressionRenamer);
 
+  // Rename property names directly used as an identifier.
   std::unordered_map<gd::String, gd::String> oldToNewPropertyNames = {
       {oldPropertyName, newPropertyName}};
   std::unordered_set<gd::String> removedPropertyNames;
   gd::EventsPropertyReplacer eventsPropertyReplacer(
       project.GetCurrentPlatform(), properties, oldToNewPropertyNames,
       removedPropertyNames);
-  gd::ProjectBrowserHelper::ExposeProjectEvents(project,
-                                                eventsPropertyReplacer);
+  gd::ProjectBrowserHelper::ExposeEventsBasedObjectEvents(
+      project, eventsFunctionsExtension, eventsBasedObject,
+      eventsPropertyReplacer);
 
   gd::InstructionsTypeRenamer actionRenamer = gd::InstructionsTypeRenamer(
       project,
@@ -2144,4 +2157,23 @@ std::vector<gd::String> WholeProjectRefactorer::GetAssociatedExternalEvents(
   return results;
 }
 
+void WholeProjectRefactorer::RenameLeaderboards(
+    gd::Project &project,
+    const std::map<gd::String, gd::String> &leaderboardIdMap) {
+  gd::LeaderboardIdRenamer leaderboardIdRenamer(project);
+  leaderboardIdRenamer.SetLeaderboardIdsToReplace(leaderboardIdMap);
+
+  gd::ProjectBrowserHelper::ExposeProjectEvents(project, leaderboardIdRenamer);
+  gd::ProjectBrowserHelper::ExposeProjectObjects(project, leaderboardIdRenamer);
+}
+
+std::set<gd::String> WholeProjectRefactorer::FindAllLeaderboardIds(gd::Project &project) {
+  gd::LeaderboardIdRenamer leaderboardIdRenamer(project);
+
+  gd::ProjectBrowserHelper::ExposeProjectEvents(project, leaderboardIdRenamer);
+  gd::ProjectBrowserHelper::ExposeProjectObjects(project, leaderboardIdRenamer);
+
+  return leaderboardIdRenamer.GetAllLeaderboardIds();
+}
+
 } // namespace gd

Core/GDCore/IDE/WholeProjectRefactorer.h

@@ -627,6 +627,18 @@ class GD_CORE_API WholeProjectRefactorer {
                                  const gd::String &originLayerName,
                                  const gd::String &targetLayerName);
 
+  /**
+   * \brief Replace the leaderboard ids in the whole project.
+   */
+  static void
+  RenameLeaderboards(gd::Project &project,
+                     const std::map<gd::String, gd::String> &leaderboardIdMap);
+
+  /**
+   * \brief Find all the leaderboard identifiers in the whole project.
+   */
+  static std::set<gd::String> FindAllLeaderboardIds(gd::Project &project);
+
   /**
    * \brief Return the number of instances on the layer named \a layerName and
    * all its associated layouts.

Core/GDCore/Project/BehaviorConfigurationContainer.cpp

@@ -6,6 +6,7 @@
 #include "GDCore/Project/BehaviorConfigurationContainer.h"
 #include <iostream>
 #include "GDCore/Project/PropertyDescriptor.h"
+#include "GDCore/IDE/Project/ArbitraryResourceWorker.h"
 
 namespace gd {
 
@@ -22,4 +23,48 @@ std::map<gd::String, gd::PropertyDescriptor> BehaviorConfigurationContainer::Get
   return nothing;
 }
 
+void BehaviorConfigurationContainer::ExposeResources(gd::ArbitraryResourceWorker& worker) {
+  std::map<gd::String, gd::PropertyDescriptor> properties = GetProperties();
+
+  for (auto& property : properties) {
+    const String& propertyName = property.first;
+    const gd::PropertyDescriptor& propertyDescriptor = property.second;
+
+    if (propertyDescriptor.GetType().LowerCase() == "resource") {
+      auto& extraInfo = propertyDescriptor.GetExtraInfo();
+      const gd::String& resourceType = extraInfo.empty() ? "" : extraInfo[0];
+      const gd::String& oldPropertyValue = propertyDescriptor.GetValue();
+
+      gd::String newPropertyValue = oldPropertyValue;
+      if (resourceType == "image") {
+        worker.ExposeImage(newPropertyValue);
+      } else if (resourceType == "audio") {
+        worker.ExposeAudio(newPropertyValue);
+      } else if (resourceType == "font") {
+        worker.ExposeFont(newPropertyValue);
+      } else if (resourceType == "video") {
+        worker.ExposeVideo(newPropertyValue);
+      } else if (resourceType == "json") {
+        worker.ExposeJson(newPropertyValue);
+      } else if (resourceType == "tilemap") {
+        worker.ExposeTilemap(newPropertyValue);
+      } else if (resourceType == "tileset") {
+        worker.ExposeTileset(newPropertyValue);
+      } else if (resourceType == "bitmapFont") {
+        worker.ExposeBitmapFont(newPropertyValue);
+      } else if (resourceType == "model3D") {
+        worker.ExposeModel3D(newPropertyValue);
+      } else if (resourceType == "atlas") {
+        worker.ExposeAtlas(newPropertyValue);
+      } else if (resourceType == "spine") {
+        worker.ExposeSpine(newPropertyValue);
+      }
+
+      if (newPropertyValue != oldPropertyValue) {
+        UpdateProperty(propertyName, newPropertyValue);
+      }
+    }
+  }
+}
+
 }  // namespace gd

Core/GDCore/Project/BehaviorConfigurationContainer.h

@@ -3,8 +3,7 @@
  * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
  * reserved. This project is released under the MIT License.
  */
-#ifndef GDCORE_BEHAVIORCONFIGURATIONCONTAINER_H
-#define GDCORE_BEHAVIORCONFIGURATIONCONTAINER_H
+#pragma once
 
 #include <map>
 #include <memory>
@@ -19,6 +18,7 @@ class PropertyDescriptor;
 class SerializerElement;
 class Project;
 class Layout;
+class ArbitraryResourceWorker;
 }  // namespace gd
 
 namespace gd {
@@ -158,6 +158,18 @@ class GD_CORE_API BehaviorConfigurationContainer {
     return propertiesQuickCustomizationVisibilities;
   }
 
+  /**
+   * \brief Called ( e.g. during compilation ) so as to inventory internal
+   * resources and sometimes update their filename. Implementation example:
+   * \code
+   * worker.ExposeImage(myImage);
+   * worker.ExposeFile(myResourceFile);
+   * \endcode
+   *
+   * \see ArbitraryResourceWorker
+   */
+  void ExposeResources(gd::ArbitraryResourceWorker& worker);
+
  protected:
   /**
    * \brief Called when the IDE wants to know about the custom properties of the
@@ -209,5 +221,3 @@ class GD_CORE_API BehaviorConfigurationContainer {
 };
 
 }  // namespace gd
-
-#endif  // GDCORE_BEHAVIORCONFIGURATIONCONTAINER_H

Core/GDCore/Project/CustomConfigurationHelper.cpp

@@ -26,7 +26,7 @@ void CustomConfigurationHelper::InitializeContent(
 
     if (propertyType == "String" || propertyType == "Choice" ||
         propertyType == "Color" || propertyType == "Behavior" ||
-        propertyType == "Resource") {
+        propertyType == "Resource" || propertyType == "LeaderboardId") {
       element.SetStringValue(property->GetValue());
     } else if (propertyType == "Number") {
       element.SetDoubleValue(property->GetValue().To<double>());
@@ -53,7 +53,7 @@ std::map<gd::String, gd::PropertyDescriptor> CustomConfigurationHelper::GetPrope
     if (configurationContent.HasChild(propertyName)) {
       if (propertyType == "String" || propertyType == "Choice" ||
           propertyType == "Color" || propertyType == "Behavior" ||
-          propertyType == "Resource") {
+          propertyType == "Resource" || propertyType == "LeaderboardId") {
         newProperty.SetValue(
             configurationContent.GetChild(propertyName).GetStringValue());
       } else if (propertyType == "Number") {
@@ -89,7 +89,7 @@ bool CustomConfigurationHelper::UpdateProperty(
 
   if (propertyType == "String" || propertyType == "Choice" ||
       propertyType == "Color" || propertyType == "Behavior" ||
-      propertyType == "Resource") {
+      propertyType == "Resource" || propertyType == "LeaderboardId") {
     element.SetStringValue(newValue);
   } else if (propertyType == "Number") {
     element.SetDoubleValue(newValue.To<double>());

Core/GDCore/Project/CustomObjectConfiguration.cpp

@@ -72,7 +72,7 @@ gd::ObjectConfiguration &CustomObjectConfiguration::GetChildObjectConfiguration(
   }
 
   if (!eventsBasedObject->GetObjects().HasObjectNamed(objectName)) {
-    gd::LogError("Tried to get the configuration of a child-object:" + objectName
+    gd::LogError("Tried to get the configuration of a child-object: " + objectName
                 + " that doesn't exist in the event-based object: " + GetType());
     return badObjectConfiguration;
   }
@@ -158,7 +158,9 @@ bool CustomObjectConfiguration::UpdateInitialInstanceProperty(
 void CustomObjectConfiguration::DoSerializeTo(SerializerElement& element) const {
   element.AddChild("content") = objectContent;
 
-  if (!animations.HasNoAnimations()) {
+  const auto *eventsBasedObject = GetEventsBasedObject();
+  if (!animations.HasNoAnimations() ||
+      (eventsBasedObject && eventsBasedObject->IsAnimatable())) {
     auto &animatableElement = element.AddChild("animatable");
     animations.SerializeTo(animatableElement);
   }
@@ -202,8 +204,8 @@ void CustomObjectConfiguration::ExposeResources(gd::ArbitraryResourceWorker& wor
 
   for (auto& property : properties) {
     const String& propertyName = property.first;
-    const gd::PropertyDescriptor& propertyDescriptor = property.second;
-    if (propertyDescriptor.GetType() == "resource") {
+    const gd::PropertyDescriptor &propertyDescriptor = property.second;
+    if (propertyDescriptor.GetType().LowerCase() == "resource") {
       auto& extraInfo = propertyDescriptor.GetExtraInfo();
       const gd::String& resourceType = extraInfo.empty() ? "" : extraInfo[0];
       const gd::String& oldPropertyValue = propertyDescriptor.GetValue();

Core/GDCore/Project/CustomObjectConfiguration.h

@@ -140,12 +140,12 @@ protected:
 
   bool IsOverridingEventsBasedObjectChildrenConfiguration() const;
 
-  const Project* project; ///< The project is used to get the
-                          ///< EventBasedObject from the fullType.
+  const Project* project = nullptr; ///< The project is used to get the
+                                    ///< EventBasedObject from the fullType.
   gd::SerializerElement objectContent;
   std::unordered_set<gd::String> unfoldedChildren;
 
-  bool isMarkedAsOverridingEventsBasedObjectChildrenConfiguration;
+  bool isMarkedAsOverridingEventsBasedObjectChildrenConfiguration = false;
   mutable std::map<gd::String, std::unique_ptr<gd::ObjectConfiguration>> childObjectConfigurations;
 
   static gd::ObjectConfiguration badObjectConfiguration;

Core/GDCore/Project/EventsBasedObject.cpp

@@ -23,7 +23,8 @@ EventsBasedObject::EventsBasedObject()
     areaMinZ(0),
     areaMaxX(64),
     areaMaxY(64),
-    areaMaxZ(64) {
+    areaMaxZ(64),
+    objectsContainer(gd::ObjectsContainer::SourceType::Object) {
 }
 
 EventsBasedObject::~EventsBasedObject() {}
@@ -90,7 +91,7 @@ void EventsBasedObject::UnserializeFrom(gd::Project& project,
   }
 
   initialInstances.UnserializeFrom(element.GetChild("instances"));
-  if (element.HasAttribute("isUsingLegacyInstancesRenderer")) {
+  if (element.HasChild("isUsingLegacyInstancesRenderer")) {
     isUsingLegacyInstancesRenderer =
         element.GetBoolAttribute("isUsingLegacyInstancesRenderer", false);
   }

Core/GDCore/Project/EventsFunctionsExtension.cpp

@@ -10,6 +10,7 @@
 #include "EventsFunction.h"
 #include "GDCore/Serialization/SerializerElement.h"
 #include "GDCore/Tools/MakeUnique.h"
+#include "GDCore/Extensions/PlatformExtension.h"
 
 namespace gd {
 
@@ -98,8 +99,11 @@ void EventsFunctionsExtension::SerializeTo(SerializerElement& element) const {
 
 void EventsFunctionsExtension::UnserializeFrom(
     gd::Project& project, const SerializerElement& element) {
-      UnserializeExtensionDeclarationFrom(project, element);
-      UnserializeExtensionImplementationFrom(project, element);
+  // Unserialize first the "declaration" (everything but objects content)
+  // so that objects can be then unserialized in proper order (they can depend
+  // on each others)
+  UnserializeExtensionDeclarationFrom(project, element);
+  UnserializeExtensionImplementationFrom(project, element);
 }
 
 void EventsFunctionsExtension::UnserializeExtensionDeclarationFrom(
@@ -162,6 +166,7 @@ void EventsFunctionsExtension::UnserializeExtensionDeclarationFrom(
   // As event based objects can contains objects using CustomBehavior and/or
   // CustomObject, this allows them to reference EventBasedBehavior and
   // EventBasedObject respectively.
+  eventsBasedBehaviors.Clear();
   auto &behaviorsElement = element.GetChild("eventsBasedBehaviors");
   behaviorsElement.ConsiderAsArrayOf("eventsBasedBehavior");
   for (std::size_t i = 0; i < behaviorsElement.GetChildrenCount(); ++i) {
@@ -169,6 +174,7 @@ void EventsFunctionsExtension::UnserializeExtensionDeclarationFrom(
         behaviorsElement.GetChild(i).GetStringAttribute("name");
     eventsBasedBehaviors.InsertNew(behaviorName, eventsBasedBehaviors.GetCount());
   }
+  eventsBasedObjects.Clear();
   auto &objectsElement = element.GetChild("eventsBasedObjects");
   objectsElement.ConsiderAsArrayOf("eventsBasedObject");
   for (std::size_t i = 0; i < objectsElement.GetChildrenCount(); ++i) {
@@ -185,11 +191,93 @@ void EventsFunctionsExtension::UnserializeExtensionImplementationFrom(
   eventsBasedBehaviors.UnserializeElementsFrom(
       "eventsBasedBehavior", project, element.GetChild("eventsBasedBehaviors"));
 
-  // It's important to load the objects without erasing them first as each object
-  // might reference other objects, and so need to know if a custom object exists
-  // in the project or not.
-  eventsBasedObjects.ProgressivelyUnserializeElementsFrom(
-      "eventsBasedObject", project, element.GetChild("eventsBasedObjects"));
+  auto &eventsBasedObjectsElement = element.GetChild("eventsBasedObjects");
+  eventsBasedObjectsElement.ConsiderAsArrayOf("eventsBasedObject");
+  for (gd::String &eventsBasedObjectName :
+       GetUnserializingOrderEventsBasedObjectNames(eventsBasedObjectsElement)) {
+    size_t extensionIndex = eventsBasedObjects.GetPosition(
+        eventsBasedObjects.Get(eventsBasedObjectName));
+    const SerializerElement &eventsBasedObjectElement =
+        eventsBasedObjectsElement.GetChild(extensionIndex);
+
+    eventsBasedObjects.at(extensionIndex)
+        .UnserializeFrom(project, eventsBasedObjectElement);
+  }
+}
+
+std::vector<gd::String>
+EventsFunctionsExtension::GetUnserializingOrderEventsBasedObjectNames(
+    const gd::SerializerElement &eventsBasedObjectsElement) {
+
+  // Child-objects need the event-based objects they use to be loaded completely
+  // before they are unserialized.
+
+  // At the beginning, everything is yet to be loaded.
+  std::vector<gd::String> remainingEventsBasedObjectNames(
+      eventsBasedObjects.size());
+  for (std::size_t i = 0; i < eventsBasedObjects.size(); ++i) {
+    remainingEventsBasedObjectNames[i] = eventsBasedObjects.at(i).GetName();
+  }
+
+  // Helper allowing to find if an object depends on at least one other object from
+  // the extension that is not loaded yet.
+  auto &extensionName = name;
+  auto isDependentFromRemainingEventsBasedObjects =
+      [&remainingEventsBasedObjectNames,
+       &extensionName](const gd::SerializerElement &eventsBasedObjectElement) {
+        auto &objectsElement = eventsBasedObjectElement.GetChild("objects");
+        objectsElement.ConsiderAsArrayOf("object");
+
+        for (std::size_t objectIndex = 0;
+             objectIndex < objectsElement.GetChildrenCount(); ++objectIndex) {
+          const gd::String &objectType =
+              objectsElement.GetChild(objectIndex).GetStringAttribute("type");
+
+          gd::String usedExtensionName =
+              PlatformExtension::GetExtensionFromFullObjectType(objectType);
+          if (usedExtensionName != extensionName) {
+            // The object comes from another extension: the project is already responsible
+            // for loading extensions in the proper order.
+            continue;
+          }
+          gd::String eventsBasedObjectName =
+              gd::PlatformExtension::GetObjectNameFromFullObjectType(
+                  objectType);
+
+          if (std::find(remainingEventsBasedObjectNames.begin(),
+                        remainingEventsBasedObjectNames.end(),
+                        eventsBasedObjectName) !=
+              remainingEventsBasedObjectNames.end()) {
+            return true;
+          }
+        }
+        return false;
+      };
+
+  // Find the order of loading so that the objects are loaded when all the objects
+  // they depend on are already loaded.
+  std::vector<gd::String> loadOrderEventsBasedObjectNames;
+  bool foundAnyEventsBasedObject = true;
+  while (foundAnyEventsBasedObject) {
+    foundAnyEventsBasedObject = false;
+    for (std::size_t i = 0; i < remainingEventsBasedObjectNames.size(); ++i) {
+      auto eventsBasedObjectName = remainingEventsBasedObjectNames[i];
+      size_t extensionIndex = eventsBasedObjects.GetPosition(
+          eventsBasedObjects.Get(eventsBasedObjectName));
+      const SerializerElement &eventsBasedObjectElement =
+          eventsBasedObjectsElement.GetChild(extensionIndex);
+
+      if (!isDependentFromRemainingEventsBasedObjects(
+              eventsBasedObjectElement)) {
+        loadOrderEventsBasedObjectNames.push_back(eventsBasedObjectName);
+        remainingEventsBasedObjectNames.erase(
+            remainingEventsBasedObjectNames.begin() + i);
+        i--;
+        foundAnyEventsBasedObject = true;
+      }
+    }
+  }
+  return loadOrderEventsBasedObjectNames;
 }
 
 bool EventsFunctionsExtension::IsExtensionLifecycleEventsFunction(

Core/GDCore/Project/EventsFunctionsExtension.h

@@ -314,6 +314,9 @@ class GD_CORE_API EventsFunctionsExtension : public EventsFunctionsContainer {
     return dependency;
   }
 
+  std::vector<gd::String> GetUnserializingOrderEventsBasedObjectNames(
+    const gd::SerializerElement &eventsBasedObjectsElement);
+
   gd::String version;
   gd::String extensionNamespace;
   gd::String shortDescription;

Core/GDCore/Project/ExternalEvents.cpp

@@ -7,7 +7,7 @@
 
 namespace gd {
 
-ExternalEvents::ExternalEvents() : lastChangeTimeStamp(0) {
+ExternalEvents::ExternalEvents() {
   // ctor
 }
 
@@ -24,14 +24,12 @@ ExternalEvents& ExternalEvents::operator=(const ExternalEvents& rhs) {
 void ExternalEvents::Init(const ExternalEvents& externalEvents) {
   name = externalEvents.GetName();
   associatedScene = externalEvents.GetAssociatedLayout();
-  lastChangeTimeStamp = externalEvents.GetLastChangeTimeStamp();
   events = externalEvents.events;
 }
 
 void ExternalEvents::SerializeTo(SerializerElement& element) const {
   element.SetAttribute("name", name);
   element.SetAttribute("associatedLayout", associatedScene);
-  element.SetAttribute("lastChangeTimeStamp", (int)lastChangeTimeStamp);
   gd::EventsListSerialization::SerializeEventsTo(events,
                                                  element.AddChild("events"));
 }
@@ -41,8 +39,6 @@ void ExternalEvents::UnserializeFrom(gd::Project& project,
   name = element.GetStringAttribute("name", "", "Name");
   associatedScene =
       element.GetStringAttribute("associatedLayout", "", "AssociatedScene");
-  lastChangeTimeStamp =
-      element.GetIntAttribute("lastChangeTimeStamp", 0, "LastChangeTimeStamp");
   gd::EventsListSerialization::UnserializeEventsFrom(
       project, events, element.GetChild("events", 0, "Events"));
 }

Core/GDCore/Project/ExternalEvents.h

@@ -67,24 +67,6 @@ class GD_CORE_API ExternalEvents {
     associatedScene = name_;
   };
 
-  /**
-   * Get the latest time of the build.
-   * Used when the IDE found that the external events can be compiled separately
-   * from scene's events.
-   *
-   * \todo This is specific to GD C++ Platform
-   */
-  time_t GetLastChangeTimeStamp() const { return lastChangeTimeStamp; };
-
-  /**
-   * Change the latest time of the build of the external events.
-   *
-   * \todo This is specific to GD C++ Platform
-   */
-  void SetLastChangeTimeStamp(time_t newTimeStamp) {
-    lastChangeTimeStamp = newTimeStamp;
-  };
-
   /**
    * \brief Get the events.
    */
@@ -109,7 +91,6 @@ class GD_CORE_API ExternalEvents {
  private:
   gd::String name;
   gd::String associatedScene;
-  time_t lastChangeTimeStamp;  ///< Time of the last build
   gd::EventsList events;       ///< List of events
 
   /**
@@ -119,19 +100,6 @@ class GD_CORE_API ExternalEvents {
   void Init(const ExternalEvents& externalEvents);
 };
 
-/**
- * \brief Functor testing ExternalEvents' name
- */
-struct ExternalEventsHasName
-    : public std::binary_function<std::unique_ptr<gd::ExternalEvents>,
-                                  gd::String,
-                                  bool> {
-  bool operator()(const std::unique_ptr<gd::ExternalEvents>& externalEvents,
-                  gd::String name) const {
-    return externalEvents->GetName() == name;
-  }
-};
-
 }  // namespace gd
 
 #endif  // GDCORE_EXTERNALEVENTS_H

Core/GDCore/Project/Layer.cpp

@@ -15,6 +15,7 @@ Camera Layer::badCamera;
 
 Layer::Layer()
     : renderingType(""),
+      defaultCameraBehavior("top-left-anchored-if-never-moved"),
       isVisible(true),
       isLocked(false),
       isLightingLayer(false),
@@ -40,6 +41,9 @@ void Layer::SerializeTo(SerializerElement& element) const {
   element.SetAttribute("name", GetName());
   element.SetAttribute("renderingType", GetRenderingType());
   element.SetAttribute("cameraType", GetCameraType());
+  if (GetDefaultCameraBehavior() != "top-left-anchored-if-never-moved") {
+    element.SetAttribute("defaultCameraBehavior", GetDefaultCameraBehavior());
+  }
   element.SetAttribute("visibility", GetVisibility());
   element.SetAttribute("isLocked", IsLocked());
   element.SetAttribute("isLightingLayer", IsLightingLayer());
@@ -80,6 +84,7 @@ void Layer::UnserializeFrom(const SerializerElement& element) {
   SetName(element.GetStringAttribute("name", "", "Name"));
   SetRenderingType(element.GetStringAttribute("renderingType", ""));
   SetCameraType(element.GetStringAttribute("cameraType", "perspective"));
+  SetDefaultCameraBehavior(element.GetStringAttribute("defaultCameraBehavior", "top-left-anchored-if-never-moved"));
   SetVisibility(element.GetBoolAttribute("visibility", true, "Visibility"));
   SetLocked(element.GetBoolAttribute("isLocked", false));
   SetLightingLayer(element.GetBoolAttribute("isLightingLayer", false));

Core/GDCore/Project/Layer.h

@@ -109,6 +109,12 @@ class GD_CORE_API Layer {
     renderingType = renderingType_;
   }
 
+  const gd::String& GetDefaultCameraBehavior() const { return defaultCameraBehavior; }
+
+  void SetDefaultCameraBehavior(const gd::String& defaultCameraBehavior_) {
+    defaultCameraBehavior = defaultCameraBehavior_;
+  }
+
   const gd::String& GetCameraType() const { return cameraType; }
 
   void SetCameraType(const gd::String& cameraType_) {
@@ -275,6 +281,7 @@ class GD_CORE_API Layer {
   gd::String name;           ///< The name of the layer
   gd::String renderingType;  ///< The rendering type: "" (empty), "2d", "3d" or
                              ///< "2d+3d".
+  gd::String defaultCameraBehavior;
   gd::String cameraType;
   bool isVisible;            ///< True if the layer is visible
   bool isLocked;             ///< True if the layer is locked

Core/GDCore/Project/Layout.cpp

@@ -36,7 +36,10 @@ namespace gd {
 
 gd::BehaviorsSharedData Layout::badBehaviorSharedData("", "");
 
-Layout::Layout(const Layout& other) { Init(other); }
+Layout::Layout(const Layout &other)
+    : objectsContainer(gd::ObjectsContainer::SourceType::Scene) {
+  Init(other);
+}
 
 Layout& Layout::operator=(const Layout& other) {
   if (this != &other) Init(other);
@@ -53,7 +56,8 @@ Layout::Layout()
       stopSoundsOnStartup(true),
       standardSortMethod(true),
       disableInputWhenNotFocused(true),
-      variables(gd::VariablesContainer::SourceType::Scene) {}
+      variables(gd::VariablesContainer::SourceType::Scene),
+      objectsContainer(gd::ObjectsContainer::SourceType::Scene) {}
 
 void Layout::SetName(const gd::String& name_) {
   name = name_;

Core/GDCore/Project/Layout.h

@@ -369,9 +369,9 @@ class GD_CORE_API Layout {
  private:
   gd::String name;         ///< Scene name
   gd::String mangledName;  ///< The scene name mangled by SceneNameMangler
-  unsigned int backgroundColorR;     ///< Background color Red component
-  unsigned int backgroundColorG;     ///< Background color Green component
-  unsigned int backgroundColorB;     ///< Background color Blue component
+  unsigned int backgroundColorR = 0;     ///< Background color Red component
+  unsigned int backgroundColorG = 0;     ///< Background color Green component
+  unsigned int backgroundColorB = 0;     ///< Background color Blue component
   gd::String title;                  ///< Title displayed in the window
   gd::VariablesContainer variables;  ///< Variables list
   gd::ObjectsContainer objectsContainer;
@@ -379,12 +379,12 @@ class GD_CORE_API Layout {
   gd::LayersContainer layers;
   std::map<gd::String, std::unique_ptr<gd::BehaviorsSharedData>>
       behaviorsSharedData;   ///< Initial shared datas of behaviors
-  bool stopSoundsOnStartup;  ///< True to make the scene stop all sounds at
-                             ///< startup.
-  bool standardSortMethod;   ///< True to sort objects using standard sort.
-  bool disableInputWhenNotFocused;  /// If set to true, the input must be
-                                    /// disabled when the window do not have the
-                                    /// focus.
+  bool stopSoundsOnStartup = true;  ///< True to make the scene stop all sounds at
+                                    ///< startup.
+  bool standardSortMethod = true;   ///< True to sort objects using standard sort.
+  bool disableInputWhenNotFocused = true;  /// If set to true, the input must be
+                                           /// disabled when the window do not have the
+                                           /// focus.
   static gd::BehaviorsSharedData
       badBehaviorSharedData;  ///< Null object, returned when
                               ///< GetBehaviorSharedData can not find the

Core/GDCore/Project/ObjectFolderOrObject.h

@@ -193,7 +193,7 @@ class GD_CORE_API ObjectFolderOrObject {
   static gd::ObjectFolderOrObject badObjectFolderOrObject;
 
   gd::ObjectFolderOrObject*
-      parent;  // nullptr if root folder, points to the parent folder otherwise.
+      parent = nullptr;  // nullptr if root folder, points to the parent folder otherwise.
   QuickCustomization::Visibility quickCustomizationVisibility;
 
   // Representing an object:

Core/GDCore/Project/ObjectGroup.h

@@ -20,8 +20,8 @@ namespace gd {
 /**
  * \brief Represents an object group.
  *
- * Objects groups do not really contains objects : They are just used in events,
- * so as to create events which can be applied to several objects.
+ * Objects groups do not really contains objects: they are just used in events,
+ * to create events which can be applied to several objects.
  *
  * \ingroup PlatformDefinition
  */

Core/GDCore/Project/ObjectsContainer.cpp

@@ -16,7 +16,9 @@
 
 namespace gd {
 
-ObjectsContainer::ObjectsContainer() {
+ObjectsContainer::ObjectsContainer(
+    const ObjectsContainer::SourceType sourceType_)
+    : sourceType(sourceType_) {
   rootFolder = gd::make_unique<gd::ObjectFolderOrObject>("__ROOT");
 }
 
@@ -34,6 +36,7 @@ ObjectsContainer& ObjectsContainer::operator=(
 }
 
 void ObjectsContainer::Init(const gd::ObjectsContainer& other) {
+  sourceType = other.sourceType;
   initialObjects = gd::Clone(other.initialObjects);
   objectGroups = other.objectGroups;
   // The objects folders are not copied.
@@ -205,6 +208,14 @@ void ObjectsContainer::MoveObjectFolderOrObjectToAnotherContainerInFolder(
       objectFolderOrObject, newParentFolder, newPosition);
 }
 
+std::set<gd::String> ObjectsContainer::GetAllObjectNames() const {
+  std::set<gd::String> names;
+  for (const auto& object : initialObjects) {
+    names.insert(object->GetName());
+  }
+  return names;
+}
+
 std::vector<const ObjectFolderOrObject*>
 ObjectsContainer::GetAllObjectFolderOrObjects() const {
   std::vector<const ObjectFolderOrObject*> results;

Core/GDCore/Project/ObjectsContainer.h

@@ -3,10 +3,11 @@
  * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
  * reserved. This project is released under the MIT License.
  */
-#ifndef GDCORE_OBJECTSCONTAINER_H
-#define GDCORE_OBJECTSCONTAINER_H
+#pragma once
+
 #include <memory>
 #include <vector>
+#include <set>
 #include "GDCore/String.h"
 #include "GDCore/Project/ObjectGroupsContainer.h"
 #include "GDCore/Project/ObjectFolderOrObject.h"
@@ -35,15 +36,25 @@ namespace gd {
  */
 class GD_CORE_API ObjectsContainer {
  public:
+  enum SourceType {
+      Unknown,
+      Global,
+      Scene,
+      Object,
+      Function,
+  };
+
   /**
-   * \brief Default constructor creating a container without any objects.
+   * \brief Constructor creating a container without any objects.
    */
-  ObjectsContainer();
+  ObjectsContainer(const SourceType sourceType);
   virtual ~ObjectsContainer();
-  
+
   ObjectsContainer(const ObjectsContainer&);
   ObjectsContainer& operator=(const ObjectsContainer& rhs);
 
+  SourceType GetSourceType() const { return sourceType; }
+
   /** \name Objects management
    * Members functions related to objects management.
    */
@@ -57,7 +68,7 @@ class GD_CORE_API ObjectsContainer {
   /**
    * \brief Return a reference to the object called \a name.
    */
-  Object& GetObject(const gd::String& name);
+  gd::Object& GetObject(const gd::String& name);
 
   /**
    * \brief Return a reference to the object called \a name.
@@ -68,7 +79,7 @@ class GD_CORE_API ObjectsContainer {
    * \brief Return a reference to the object at position \a index in the objects
    * list
    */
-  Object& GetObject(std::size_t index);
+  gd::Object& GetObject(std::size_t index);
 
   /**
    * \brief Return a reference to the object at position \a index in the objects
@@ -168,6 +179,8 @@ class GD_CORE_API ObjectsContainer {
   const std::vector<std::unique_ptr<gd::Object> >& GetObjects() const {
     return initialObjects;
   }
+
+  std::set<gd::String> GetAllObjectNames() const;
   ///@}
 
   /**
@@ -232,6 +245,7 @@ class GD_CORE_API ObjectsContainer {
   gd::ObjectGroupsContainer objectGroups;
 
  private:
+  SourceType sourceType = Unknown;
   std::unique_ptr<gd::ObjectFolderOrObject> rootFolder;
 
   /**
@@ -242,5 +256,3 @@ class GD_CORE_API ObjectsContainer {
 };
 
 }  // namespace gd
-
-#endif  // GDCORE_OBJECTSCONTAINER_H

Core/GDCore/Project/ObjectsContainersList.cpp

@@ -416,7 +416,8 @@ gd::String ObjectsContainersList::GetTypeOfObject(
     return "";
   }
   if (objectsContainers.size() == 1) {
-    gd::ObjectsContainer emptyObjectsContainer;
+    gd::ObjectsContainer emptyObjectsContainer(
+        gd::ObjectsContainer::SourceType::Unknown);
     return gd::GetTypeOfObject(emptyObjectsContainer, *objectsContainers[0],
                                objectName, true);
   }
@@ -439,7 +440,8 @@ bool ObjectsContainersList::HasBehaviorInObjectOrGroup(
     return false;
   }
   if (objectsContainers.size() == 1) {
-    gd::ObjectsContainer emptyObjectsContainer;
+    gd::ObjectsContainer emptyObjectsContainer(
+        gd::ObjectsContainer::SourceType::Unknown);
     return gd::HasBehaviorInObjectOrGroup(
         emptyObjectsContainer, *objectsContainers[0], objectOrGroupName,
         behaviorName, true);
@@ -468,7 +470,8 @@ gd::String ObjectsContainersList::GetTypeOfBehaviorInObjectOrGroup(
     return "";
   }
   if (objectsContainers.size() == 1) {
-    gd::ObjectsContainer emptyObjectsContainer;
+    gd::ObjectsContainer emptyObjectsContainer(
+        gd::ObjectsContainer::SourceType::Unknown);
     return gd::GetTypeOfBehaviorInObjectOrGroup(
         emptyObjectsContainer, *objectsContainers[0], objectOrGroupName,
         behaviorName, searchInGroups);
@@ -495,7 +498,8 @@ gd::String ObjectsContainersList::GetTypeOfBehavior(
     return "";
   }
   if (objectsContainers.size() == 1) {
-    gd::ObjectsContainer emptyObjectsContainer;
+    gd::ObjectsContainer emptyObjectsContainer(
+        gd::ObjectsContainer::SourceType::Unknown);
     return gd::GetTypeOfBehavior(emptyObjectsContainer, *objectsContainers[0],
                                  behaviorName, searchInGroups);
   }
@@ -521,7 +525,8 @@ std::vector<gd::String> ObjectsContainersList::GetBehaviorsOfObject(
     return behaviors;
   }
   if (objectsContainers.size() == 1) {
-    gd::ObjectsContainer emptyObjectsContainer;
+    gd::ObjectsContainer emptyObjectsContainer(
+        gd::ObjectsContainer::SourceType::Unknown);
     return gd::GetBehaviorsOfObject(emptyObjectsContainer,
                                     *objectsContainers[0], objectName,
                                     searchInGroups);
@@ -530,6 +535,33 @@ std::vector<gd::String> ObjectsContainersList::GetBehaviorsOfObject(
       *objectsContainers[0], *objectsContainers[1], objectName, searchInGroups);
 }
 
+std::vector<gd::String> ObjectsContainersList::GetBehaviorNamesInObjectOrGroup(
+    const gd::String &objectOrGroupName, const gd::String &behaviorType, bool searchInGroups) const {
+  if (objectsContainers.size() > 2) {
+    // TODO: rework forwarded methods so they can work with any number of
+    // containers.
+    gd::LogFatalError(
+        "ObjectsContainersList::GetBehaviorNamesInObjectOrGroup called with objectsContainers "
+        "not being exactly 2. This is a logical error and will crash.");
+  }
+  if (objectsContainers.size() == 0) {
+    gd::LogWarning("ObjectsContainersList::GetBehaviorNamesInObjectOrGroup called without any "
+                   "objectsContainer");
+    std::vector<gd::String> behaviors;
+    return behaviors;
+  }
+  if (objectsContainers.size() == 1) {
+    gd::ObjectsContainer emptyObjectsContainer(
+        gd::ObjectsContainer::SourceType::Unknown);
+    return gd::GetBehaviorNamesInObjectOrGroup(emptyObjectsContainer,
+                                    *objectsContainers[0], objectOrGroupName, behaviorType,
+                                    searchInGroups);
+  }
+  return gd::GetBehaviorNamesInObjectOrGroup(
+      *objectsContainers[0], *objectsContainers[1], objectOrGroupName, behaviorType, searchInGroups);
+}
+
+
 std::vector<gd::String> ObjectsContainersList::GetAnimationNamesOfObject(
     const gd::String &objectOrGroupName) const {
   std::vector<gd::String> animationNames;
@@ -589,6 +621,28 @@ std::vector<gd::String> ObjectsContainersList::GetAnimationNamesOfObject(
   return animationNames;
 }
 
+const ObjectsContainer *
+ObjectsContainersList::GetObjectsContainerFromObjectName(
+    const gd::String &objectOrGroupName) const {
+  for (auto it = objectsContainers.rbegin(); it != objectsContainers.rend();
+       ++it) {
+    if ((*it)->HasObjectNamed(objectOrGroupName) ||
+        (*it)->GetObjectGroups().Has(objectOrGroupName)) {
+      return *it;
+    }
+  }
+  return nullptr;
+}
+
+const gd::ObjectsContainer::SourceType
+ObjectsContainersList::GetObjectsContainerSourceType(
+    const gd::String &objectOrGroupName) const {
+  const auto *objectsContainer =
+      GetObjectsContainerFromObjectName(objectOrGroupName);
+  return objectsContainer ? objectsContainer->GetSourceType()
+                          : gd::ObjectsContainer::SourceType::Unknown;
+}
+
 const gd::ObjectsContainer &
 ObjectsContainersList::GetObjectsContainer(std::size_t index) const {
   return *objectsContainers[index];

Core/GDCore/Project/ObjectsContainersList.h

@@ -2,12 +2,12 @@
 #include <vector>
 
 #include "Variable.h"
+#include "GDCore/Project/ObjectsContainer.h"
 
 namespace gd {
 class String;
 class Project;
 class Layout;
-class ObjectsContainer;
 class VariablesContainer;
 class Object;
 class ObjectConfiguration;
@@ -50,6 +50,11 @@ class GD_CORE_API ObjectsContainersList {
    */
   bool HasObjectOrGroupNamed(const gd::String& name) const;
 
+  /**
+   * \brief Check if the specified object exists ignoring groups.
+   */
+  bool HasObjectNamed(const gd::String& name) const;
+
   enum VariableExistence {
     DoesNotExist,
     Exists,
@@ -128,6 +133,18 @@ class GD_CORE_API ObjectsContainersList {
   std::vector<gd::String> GetBehaviorsOfObject(
       const gd::String& objectName, bool searchInGroups = true) const;
 
+  /**
+   * \brief Get behaviors of an object/group of a given behavior type.
+   * \note The behaviors of a group are the behaviors which are found in common
+   * when looking all the objects of the group.
+   *
+   * @return Vector containing names of behaviors
+   */
+  std::vector<gd::String>
+  GetBehaviorNamesInObjectOrGroup(const gd::String &objectOrGroupName,
+                       const gd::String &behaviorType,
+                       bool searchInGroups = true) const;
+
   /**
    * \brief Get the animation names of an object/group.
    * \note The animation names of a group are the animation names common to
@@ -173,8 +190,28 @@ class GD_CORE_API ObjectsContainersList {
       std::function<void(const gd::String& variableName,
                          const gd::Variable& variable)> fn) const;
 
+  /**
+   * \brief Return the source type of the container for the specified object or
+   * group of objects.
+   */
+  const gd::ObjectsContainer::SourceType GetObjectsContainerSourceType(
+      const gd::String& objectOrGroupName) const;
+
+  /**
+   * Get the objects container for for the specified object or group of objects.
+   */
+  const ObjectsContainer *
+  GetObjectsContainerFromObjectName(const gd::String &objectOrGroupName) const;
+
   /**
    * \brief Return a the objects container at position \a index.
+   *
+   * \warning The returned `ObjectsContainer` may contain cloned objects (in the case of
+   * `ProjectScopedContainers::MakeNewProjectScopedContainersForEventsBasedObject`)
+   * or "fake" objects used by events like parameters. They must not be used to
+   * edit the objects.
+   * Search for "ProjectScopedContainers wrongly containing temporary objects containers or objects"
+   * in the codebase.
    */
   const gd::ObjectsContainer &GetObjectsContainer(std::size_t index) const;
 
@@ -188,8 +225,6 @@ class GD_CORE_API ObjectsContainersList {
   ObjectsContainersList(){};
 
  private:
-  bool HasObjectNamed(const gd::String& name) const;
-
   const gd::Object* GetObject(const gd::String& name) const;
 
   bool HasObjectWithVariableNamed(const gd::String& objectName,

Core/GDCore/Project/Project.cpp

@@ -71,23 +71,22 @@ Project::Project()
       isPlayableWithKeyboard(false),
       isPlayableWithGamepad(false),
       isPlayableWithMobile(false),
-      currentPlatform(NULL),
+      currentPlatform(nullptr),
       gdMajorVersion(gd::VersionWrapper::Major()),
       gdMinorVersion(gd::VersionWrapper::Minor()),
       gdBuildVersion(gd::VersionWrapper::Build()),
-      variables(gd::VariablesContainer::SourceType::Global) {}
+      variables(gd::VariablesContainer::SourceType::Global),
+      objectsContainer(gd::ObjectsContainer::SourceType::Global) {}
 
 Project::~Project() {}
 
 void Project::ResetProjectUuid() { projectUuid = UUID::MakeUuid4(); }
 
-std::unique_ptr<gd::Object> Project::CreateObject(
-    const gd::String& objectType, const gd::String& name) const {
-  std::unique_ptr<gd::Object> object = gd::make_unique<Object>(
-      name, objectType, CreateObjectConfiguration(objectType));
-
+void Project::EnsureObjectDefaultBehaviors(gd::Object& object) const {
   auto& platform = GetCurrentPlatform();
   auto& project = *this;
+  auto& objectType = object.GetType();
+
   auto addDefaultBehavior = [&platform, &project, &object, &objectType](
                                 const gd::String& behaviorType) {
     auto& behaviorMetadata =
@@ -97,17 +96,47 @@ std::unique_ptr<gd::Object> Project::CreateObject(
                      " has an unknown default behavior: " + behaviorType);
       return;
     }
-    auto* behavior = object->AddNewBehavior(
-        project, behaviorType, behaviorMetadata.GetDefaultName());
-    behavior->SetDefaultBehavior(true);
+
+    const gd::String& behaviorName = behaviorMetadata.GetDefaultName();
+
+    // Check if we can keep a behavior that would have been already set up on the object.
+    if (object.HasBehaviorNamed(behaviorName)) {
+      const auto& behavior = object.GetBehavior(behaviorName);
+
+      if (!behavior.IsDefaultBehavior() || behavior.GetTypeName() != behaviorType) {
+        // Behavior type has changed, remove it so it is re-created.
+        object.RemoveBehavior(behaviorName);
+      }
+    }
+
+    if (!object.HasBehaviorNamed(behaviorName)) {
+      auto* behavior = object.AddNewBehavior(
+          project, behaviorType, behaviorName);
+      behavior->SetDefaultBehavior(true);
+    }
   };
 
   auto &objectMetadata =
       gd::MetadataProvider::GetObjectMetadata(platform, objectType);
   if (!MetadataProvider::IsBadObjectMetadata(objectMetadata)) {
-    for (auto &behaviorType : objectMetadata.GetDefaultBehaviors()) {
+    // Add all default behaviors.
+    const auto& defaultBehaviorTypes = objectMetadata.GetDefaultBehaviors();
+    for (auto &behaviorType : defaultBehaviorTypes) {
       addDefaultBehavior(behaviorType);
     }
+
+    // Ensure there are no default behaviors that would not be required left on the object.
+    for (const auto& behaviorName : object.GetAllBehaviorNames()) {
+      auto& behavior = object.GetBehavior(behaviorName);
+      if (!behavior.IsDefaultBehavior()) {
+        // Non default behaviors are not handled by this function.
+        continue;
+      }
+
+      if (defaultBehaviorTypes.find(behavior.GetTypeName()) == defaultBehaviorTypes.end()) {
+        object.RemoveBehavior(behaviorName);
+      }
+    }
   }
   // During project deserialization, event-based object metadata are not yet
   // generated. Default behaviors will be added by
@@ -115,6 +144,14 @@ std::unique_ptr<gd::Object> Project::CreateObject(
   else if (!project.HasEventsBasedObject(objectType)) {
     gd::LogWarning("Object: " + name + " has an unknown type: " + objectType);
   }
+}
+
+std::unique_ptr<gd::Object> Project::CreateObject(
+    const gd::String& objectType, const gd::String& name) const {
+  std::unique_ptr<gd::Object> object = gd::make_unique<Object>(
+      name, objectType, CreateObjectConfiguration(objectType));
+
+  EnsureObjectDefaultBehaviors(*object);
 
   return std::move(object);
 }
@@ -830,7 +867,7 @@ void Project::UnserializeFrom(const SerializerElement& element) {
   eventsFunctionsExtensionsElement.ConsiderAsArrayOf(
       "eventsFunctionsExtension");
   // First, only unserialize behaviors and objects names.
-  // As event based objects can contains CustomObject and Custom Object,
+  // As event based objects can contains custom behaviors and custom objects,
   // this allows them to reference EventBasedBehavior and EventBasedObject
   // respectively.
   for (std::size_t i = 0;
@@ -845,15 +882,17 @@ void Project::UnserializeFrom(const SerializerElement& element) {
     newEventsFunctionsExtension.UnserializeExtensionDeclarationFrom(
         *this, eventsFunctionsExtensionElement);
   }
-  // Then unserialize functions, behaviors and objects content.
-  for (std::size_t i = 0;
-       i < eventsFunctionsExtensionsElement.GetChildrenCount();
-       ++i) {
-    const SerializerElement& eventsFunctionsExtensionElement =
-        eventsFunctionsExtensionsElement.GetChild(i);
 
-    eventsFunctionsExtensions.at(i)->UnserializeExtensionImplementationFrom(
-        *this, eventsFunctionsExtensionElement);
+  // Then unserialize functions, behaviors and objects content.
+  for (gd::String &extensionName :
+       GetUnserializingOrderExtensionNames(eventsFunctionsExtensionsElement)) {
+    size_t extensionIndex = GetEventsFunctionsExtensionPosition(extensionName);
+    const SerializerElement &eventsFunctionsExtensionElement =
+        eventsFunctionsExtensionsElement.GetChild(extensionIndex);
+
+    eventsFunctionsExtensions.at(extensionIndex)
+        ->UnserializeExtensionImplementationFrom(
+            *this, eventsFunctionsExtensionElement);
   }
 
   objectsContainer.GetObjectGroups().UnserializeFrom(
@@ -922,6 +961,83 @@ void Project::UnserializeFrom(const SerializerElement& element) {
   }
 }
 
+std::vector<gd::String> Project::GetUnserializingOrderExtensionNames(
+    const gd::SerializerElement &eventsFunctionsExtensionsElement) {
+
+  // Some extension have custom objects, which have child objects coming from other extension.
+  // These child objects must be loaded completely before the parent custom obejct can be unserialized.
+  // This implies: an order on the extension unserialization (and no cycles).
+
+  // At the beginning, everything is yet to be loaded.
+  std::vector<gd::String> remainingExtensionNames(
+      eventsFunctionsExtensions.size());
+  for (std::size_t i = 0; i < eventsFunctionsExtensions.size(); ++i) {
+    remainingExtensionNames[i] = eventsFunctionsExtensions.at(i)->GetName();
+  }
+
+  // Helper allowing to find if an extension has an object that depends on
+  // at least one other object from another extension that is not loaded yet.
+  auto isDependentFromRemainingExtensions =
+      [&remainingExtensionNames](
+          const gd::SerializerElement &eventsFunctionsExtensionElement) {
+        auto &eventsBasedObjectsElement =
+            eventsFunctionsExtensionElement.GetChild("eventsBasedObjects");
+        eventsBasedObjectsElement.ConsiderAsArrayOf("eventsBasedObject");
+        for (std::size_t eventsBasedObjectsIndex = 0;
+             eventsBasedObjectsIndex <
+             eventsBasedObjectsElement.GetChildrenCount();
+             ++eventsBasedObjectsIndex) {
+          auto &objectsElement =
+              eventsBasedObjectsElement.GetChild(eventsBasedObjectsIndex)
+                  .GetChild("objects");
+          objectsElement.ConsiderAsArrayOf("object");
+
+          for (std::size_t objectIndex = 0;
+               objectIndex < objectsElement.GetChildrenCount(); ++objectIndex) {
+            const gd::String &objectType =
+                objectsElement.GetChild(objectIndex).GetStringAttribute("type");
+
+            gd::String extensionName =
+                eventsFunctionsExtensionElement.GetStringAttribute("name");
+            gd::String usedExtensionName =
+                gd::PlatformExtension::GetExtensionFromFullObjectType(objectType);
+
+            if (usedExtensionName != extensionName &&
+                std::find(remainingExtensionNames.begin(),
+                          remainingExtensionNames.end(),
+                          usedExtensionName) != remainingExtensionNames.end()) {
+              return true;
+            }
+          }
+        }
+        return false;
+      };
+
+  // Find the order of loading so that the extensions are loaded when all the other
+  // extensions they depend on are already loaded.
+  std::vector<gd::String> loadOrderExtensionNames;
+  bool foundAnyExtension = true;
+  while (foundAnyExtension) {
+    foundAnyExtension = false;
+    for (std::size_t i = 0; i < remainingExtensionNames.size(); ++i) {
+      auto extensionName = remainingExtensionNames[i];
+      size_t extensionIndex =
+          GetEventsFunctionsExtensionPosition(extensionName);
+      const SerializerElement &eventsFunctionsExtensionElement =
+          eventsFunctionsExtensionsElement.GetChild(extensionIndex);
+
+      if (!isDependentFromRemainingExtensions(
+              eventsFunctionsExtensionElement)) {
+        loadOrderExtensionNames.push_back(extensionName);
+        remainingExtensionNames.erase(remainingExtensionNames.begin() + i);
+        i--;
+        foundAnyExtension = true;
+      }
+    }
+  }
+  return loadOrderExtensionNames;
+}
+
 void Project::SerializeTo(SerializerElement& element) const {
   SerializerElement& versionElement = element.AddChild("gdVersion");
   versionElement.SetAttribute("major", gd::VersionWrapper::Major());
@@ -1151,7 +1267,10 @@ gd::SourceFile& Project::InsertNewSourceFile(const gd::String& name,
   return newlyInsertedSourceFile;
 }
 
-Project::Project(const Project& other) { Init(other); }
+Project::Project(const Project &other)
+    : objectsContainer(gd::ObjectsContainer::SourceType::Global) {
+  Init(other);
+}
 
 Project& Project::operator=(const Project& other) {
   if (this != &other) Init(other);

Core/GDCore/Project/Project.h

@@ -523,13 +523,7 @@ class GD_CORE_API Project {
   std::unique_ptr<gd::Object> CreateObject(const gd::String& type,
                                            const gd::String& name) const;
 
-  /**
-   * Create an object configuration of the given type.
-   *
-   * \param type The type of the object
-   */
-  std::unique_ptr<gd::ObjectConfiguration> CreateObjectConfiguration(
-      const gd::String& type) const;
+  void EnsureObjectDefaultBehaviors(gd::Object& object) const;
 
   /**
    * Create an event of the given type.
@@ -990,16 +984,12 @@ class GD_CORE_API Project {
   /**
    * \brief return the objects of the project.
    */
-  gd::ObjectsContainer& GetObjects() {
-    return objectsContainer;
-  }
+  gd::ObjectsContainer& GetObjects() { return objectsContainer; }
 
   /**
    * \brief Return the objects of the project.
    */
-  const gd::ObjectsContainer& GetObjects() const {
-    return objectsContainer;
-  }
+  const gd::ObjectsContainer& GetObjects() const { return objectsContainer; }
   ///@}
 
   /** \name Identifier names
@@ -1080,32 +1070,51 @@ class GD_CORE_API Project {
    */
   void Init(const gd::Project& project);
 
-  gd::String name;            ///< Game name
-  gd::String description;     ///< Game description
-  gd::String version;         ///< Game version number (used for some exports)
-  unsigned int windowWidth;   ///< Window default width
-  unsigned int windowHeight;  ///< Window default height
-  int maxFPS;                 ///< Maximum Frame Per Seconds, -1 for unlimited
-  unsigned int minFPS;  ///< Minimum Frame Per Seconds ( slow down game if FPS
-                        ///< are below this number )
-  bool verticalSync;    ///< If true, must activate vertical synchronization.
+  /**
+   * @brief Get the project extensions names in the order they have to be unserialized.
+   *
+   * Child-objects need the event-based objects they use to be loaded completely
+   * before they are unserialized.
+   */
+  std::vector<gd::String> GetUnserializingOrderExtensionNames(const gd::SerializerElement &eventsFunctionsExtensionsElement);
+
+  /**
+   * Create an object configuration of the given type.
+   *
+   * \param type The type of the object
+   */
+  std::unique_ptr<gd::ObjectConfiguration> CreateObjectConfiguration(
+      const gd::String& type) const;
+
+  gd::String name;         ///< Game name
+  gd::String description;  ///< Game description
+  gd::String version;      ///< Game version number (used for some exports)
+  unsigned int windowWidth = 0;   ///< Window default width
+  unsigned int windowHeight = 0;  ///< Window default height
+  int maxFPS = 0;           ///< Maximum Frame Per Seconds, -1 for unlimited
+  unsigned int minFPS = 0;  ///< Minimum Frame Per Seconds ( slow down game if
+                            ///< FPS are below this number )
+  bool verticalSync =
+      false;  ///< If true, must activate vertical synchronization.
   gd::String scaleMode;
-  bool pixelsRounding;  ///< If true, the rendering should stop pixel
-                        ///< interpolation of rendered objects.
-  bool adaptGameResolutionAtRuntime;  ///< Should the game resolution be adapted
-                                      ///< to the window size at runtime
+  bool pixelsRounding = false;  ///< If true, the rendering should stop pixel
+                                ///< interpolation of rendered objects.
+  bool adaptGameResolutionAtRuntime =
+      true;  ///< Should the game resolution be adapted
+             ///< to the window size at runtime
   gd::String
       sizeOnStartupMode;  ///< How to adapt the game size to the screen. Can be
                           ///< "adaptWidth", "adaptHeight" or empty
   gd::String antialiasingMode;
-  bool isAntialisingEnabledOnMobile;
+  bool isAntialisingEnabledOnMobile = false;
   gd::String projectUuid;  ///< UUID useful to identify the game in online
                            ///< services or database that would require it.
-  bool useDeprecatedZeroAsDefaultZOrder;  ///< If true, objects created from
-                                          ///< events will have 0 as Z order,
-                                          ///< instead of the highest Z order
-                                          ///< found on the layer at the scene
-                                          ///< startup.
+  bool useDeprecatedZeroAsDefaultZOrder =
+      false;  ///< If true, objects created from
+              ///< events will have 0 as Z order,
+              ///< instead of the highest Z order
+              ///< found on the layer at the scene
+              ///< startup.
   std::vector<std::unique_ptr<gd::Layout> > scenes;  ///< List of all scenes
   gd::VariablesContainer variables;  ///< Initial global variables
   gd::ObjectsContainer objectsContainer;
@@ -1118,7 +1127,8 @@ class GD_CORE_API Project {
   std::vector<gd::Platform*>
       platforms;  ///< Pointers to the platforms this project supports.
   gd::String firstLayout;
-  bool useExternalSourceFiles;  ///< True if game used external source files.
+  bool useExternalSourceFiles =
+      false;  ///< True if game used external source files.
   std::vector<std::unique_ptr<gd::SourceFile> >
       externalSourceFiles;  ///< List of external source files used.
   gd::String author;        ///< Game author name, for publishing purpose.
@@ -1127,35 +1137,40 @@ class GD_CORE_API Project {
   std::vector<gd::String>
       authorUsernames;  ///< Game author usernames, from GDevelop users DB.
   std::vector<gd::String> categories;  ///< Game categories
-  bool isPlayableWithKeyboard;  ///< The project is playable with a keyboard.
-  bool isPlayableWithGamepad;   ///< The project is playable with a gamepad.
-  bool isPlayableWithMobile;    ///< The project is playable on a mobile.
-  gd::String packageName;       ///< Game package name
+  bool isPlayableWithKeyboard =
+      false;  ///< The project is playable with a keyboard.
+  bool isPlayableWithGamepad =
+      false;  ///< The project is playable with a gamepad.
+  bool isPlayableWithMobile = false;  ///< The project is playable on a mobile.
+  gd::String packageName;             ///< Game package name
   gd::String templateSlug;  ///< The slug of the template from which the game is
                             ///< created.
   gd::String orientation;   ///< Lock game orientation (on mobile devices).
                             ///< "default", "landscape" or "portrait".
-  bool
-      folderProject;  ///< True if folder project, false if single file project.
+  bool folderProject =
+      false;  ///< True if folder project, false if single file project.
   gd::String
       projectFile;  ///< Path to the project file - when editing a local file.
   gd::String latestCompilationDirectory;
-  gd::Platform*
-      currentPlatform;  ///< The platform being used to edit the project.
+  gd::Platform* currentPlatform =
+      nullptr;  ///< The platform being used to edit the project.
   gd::PlatformSpecificAssets platformSpecificAssets;
   gd::LoadingScreen loadingScreen;
   gd::Watermark watermark;
   std::vector<std::unique_ptr<gd::ExternalEvents> >
       externalEvents;  ///< List of all externals events
   ExtensionProperties
-      extensionProperties;              ///< The properties of the extensions.
+      extensionProperties;  ///< The properties of the extensions.
   gd::WholeProjectDiagnosticReport wholeProjectDiagnosticReport;
-  mutable unsigned int gdMajorVersion;  ///< The GD major version used the last
-                                        ///< time the project was saved.
-  mutable unsigned int gdMinorVersion;  ///< The GD minor version used the last
-                                        ///< time the project was saved.
-  mutable unsigned int gdBuildVersion;  ///< The GD build version used the last
-                                        ///< time the project was saved.
+  mutable unsigned int gdMajorVersion =
+      0;  ///< The GD major version used the last
+          ///< time the project was saved.
+  mutable unsigned int gdMinorVersion =
+      0;  ///< The GD minor version used the last
+          ///< time the project was saved.
+  mutable unsigned int gdBuildVersion =
+      0;  ///< The GD build version used the last
+          ///< time the project was saved.
 };
 
 }  // namespace gd

Core/GDCore/Project/ProjectScopedContainers.cpp

@@ -4,12 +4,55 @@
 #include "GDCore/Project/EventsFunctionsExtension.h"
 #include "GDCore/Project/EventsBasedBehavior.h"
 #include "GDCore/Project/EventsBasedObject.h"
+#include "GDCore/Project/Layout.h"
 #include "GDCore/Project/ObjectsContainer.h"
+#include "GDCore/Project/Project.h"
 #include "GDCore/Events/Event.h"
 #include "GDCore/Extensions/PlatformExtension.h"
 
 namespace gd {
 
+ProjectScopedContainers
+ProjectScopedContainers::MakeNewProjectScopedContainersForProjectAndLayout(
+    const gd::Project &project, const gd::Layout &layout) {
+  ProjectScopedContainers projectScopedContainers(
+      ObjectsContainersList::MakeNewObjectsContainersListForProjectAndLayout(
+          project, layout),
+      VariablesContainersList::
+          MakeNewVariablesContainersListForProjectAndLayout(project, layout),
+      &project.GetVariables(), &layout.GetVariables(),
+      PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
+
+  return projectScopedContainers;
+}
+
+ProjectScopedContainers
+ProjectScopedContainers::MakeNewProjectScopedContainersForProject(
+    const gd::Project &project) {
+  ProjectScopedContainers projectScopedContainers(
+      ObjectsContainersList::MakeNewObjectsContainersListForProject(project),
+      VariablesContainersList::MakeNewVariablesContainersListForProject(
+          project),
+      &project.GetVariables(), nullptr,
+      PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
+
+  return projectScopedContainers;
+}
+
+ProjectScopedContainers
+ProjectScopedContainers::MakeNewProjectScopedContainersFor(
+    const gd::ObjectsContainer &globalObjectsContainers,
+    const gd::ObjectsContainer &objectsContainers) {
+  ProjectScopedContainers projectScopedContainers(
+      ObjectsContainersList::MakeNewObjectsContainersListForContainers(
+          globalObjectsContainers, objectsContainers),
+      VariablesContainersList::MakeNewEmptyVariablesContainersList(),
+      nullptr, nullptr,
+      PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
+
+  return projectScopedContainers;
+};
+
 ProjectScopedContainers
 ProjectScopedContainers::MakeNewProjectScopedContainersForEventsFunctionsExtension(
     const gd::Project &project, const gd::EventsFunctionsExtension &eventsFunctionsExtension) {
@@ -18,6 +61,8 @@ ProjectScopedContainers::MakeNewProjectScopedContainersForEventsFunctionsExtensi
       ObjectsContainersList::MakeNewEmptyObjectsContainersList(),
       VariablesContainersList::
           MakeNewVariablesContainersListForEventsFunctionsExtension(eventsFunctionsExtension),
+      &eventsFunctionsExtension.GetGlobalVariables(),
+      &eventsFunctionsExtension.GetSceneVariables(),
       PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
 
   return projectScopedContainers;
@@ -37,6 +82,8 @@ ProjectScopedContainers::MakeNewProjectScopedContainersForFreeEventsFunction(
           parameterObjectsContainer),
       VariablesContainersList::
           MakeNewVariablesContainersListForEventsFunctionsExtension(eventsFunctionsExtension),
+      &eventsFunctionsExtension.GetGlobalVariables(),
+      &eventsFunctionsExtension.GetSceneVariables(),
       PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
 
   projectScopedContainers.AddParameters(
@@ -63,6 +110,8 @@ ProjectScopedContainers::MakeNewProjectScopedContainersForBehaviorEventsFunction
           parameterObjectsContainer),
       VariablesContainersList::
           MakeNewVariablesContainersListForEventsFunctionsExtension(eventsFunctionsExtension),
+      &eventsFunctionsExtension.GetGlobalVariables(),
+      &eventsFunctionsExtension.GetSceneVariables(),
       PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
 
   projectScopedContainers.AddPropertiesContainer(
@@ -87,11 +136,14 @@ ProjectScopedContainers::MakeNewProjectScopedContainersForObjectEventsFunction(
       project, eventsBasedObject, eventsFunction, parameterObjectsContainer);
 
   ProjectScopedContainers projectScopedContainers(
-      ObjectsContainersList::MakeNewObjectsContainersListForContainer(
+      ObjectsContainersList::MakeNewObjectsContainersListForContainers(
+          eventsBasedObject.GetObjects(),
           parameterObjectsContainer),
       VariablesContainersList::
           MakeNewVariablesContainersListForEventsFunctionsExtension(
               eventsFunctionsExtension),
+      &eventsFunctionsExtension.GetGlobalVariables(),
+      &eventsFunctionsExtension.GetSceneVariables(),
       PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
 
   projectScopedContainers.AddPropertiesContainer(
@@ -109,22 +161,34 @@ ProjectScopedContainers::MakeNewProjectScopedContainersForEventsBasedObject(
     const gd::EventsBasedObject &eventsBasedObject,
     gd::ObjectsContainer &outputObjectsContainer) {
 
+  // TODO: We should avoid to use a single `outputObjectsContainer` and instead
+  // use multiple, stable objects container pointed by the `ProjectScopedContainers`
+  // created below.
+  // Search for "ProjectScopedContainers wrongly containing temporary objects containers or objects"
+  // in the codebase.
   outputObjectsContainer.GetObjects().clear();
   outputObjectsContainer.GetObjectGroups().Clear();
+
+  // This object named "Object" represents the parent and is used by events.
+  // TODO: Use a dedicated `ObjectsContainer` with only this "Object" and check in
+  // the codebase that this container is not assumed as a
+  // "globalObjectsContainer".
+  // Search for "ProjectScopedContainers wrongly containing temporary objects containers or objects"
+  // in the codebase.
   outputObjectsContainer.InsertNewObject(
       project,
       gd::PlatformExtension::GetObjectFullType(
           eventsFunctionsExtension.GetName(), eventsBasedObject.GetName()),
       "Object", outputObjectsContainer.GetObjectsCount());
-  gd::EventsFunctionTools::CopyEventsBasedObjectChildrenToObjectsContainer(
-      eventsBasedObject, outputObjectsContainer);
 
   ProjectScopedContainers projectScopedContainers(
-      ObjectsContainersList::MakeNewObjectsContainersListForContainer(
-          outputObjectsContainer),
+      ObjectsContainersList::MakeNewObjectsContainersListForContainers(
+          eventsBasedObject.GetObjects(), outputObjectsContainer),
       VariablesContainersList::
           MakeNewVariablesContainersListForEventsFunctionsExtension(
               eventsFunctionsExtension),
+      &eventsFunctionsExtension.GetGlobalVariables(),
+      &eventsFunctionsExtension.GetSceneVariables(),
       PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
 
   projectScopedContainers.AddPropertiesContainer(

Core/GDCore/Project/ProjectScopedContainers.h

@@ -5,13 +5,11 @@
 #include "ObjectsContainersList.h"
 #include "PropertiesContainersList.h"
 #include "VariablesContainersList.h"
+#include "VariablesContainer.h"
 
 namespace gd {
 class Project;
 class ObjectsContainer;
-class ObjectsContainersList;
-class VariablesContainersList;
-class PropertiesContainersList;
 class NamedPropertyDescriptor;
 class ParameterMetadataContainer;
 class BaseEvent;
@@ -19,7 +17,7 @@ class EventsFunctionsExtension;
 class EventsFunction;
 class EventsBasedBehavior;
 class EventsBasedObject;
-}  // namespace gd
+} // namespace gd
 
 namespace gd {
 
@@ -38,51 +36,29 @@ class ProjectScopedContainers {
   ProjectScopedContainers(
       const gd::ObjectsContainersList &objectsContainersList_,
       const gd::VariablesContainersList &variablesContainersList_,
+      const gd::VariablesContainer *legacyGlobalVariables_,
+      const gd::VariablesContainer *legacySceneVariables_,
       const gd::PropertiesContainersList &propertiesContainersList_)
       : objectsContainersList(objectsContainersList_),
         variablesContainersList(variablesContainersList_),
+        legacyGlobalVariables(legacyGlobalVariables_),
+        legacySceneVariables(legacySceneVariables_),
         propertiesContainersList(propertiesContainersList_){};
   virtual ~ProjectScopedContainers(){};
 
   static ProjectScopedContainers
   MakeNewProjectScopedContainersForProjectAndLayout(const gd::Project &project,
-                                                    const gd::Layout &layout) {
-    ProjectScopedContainers projectScopedContainers(
-        ObjectsContainersList::MakeNewObjectsContainersListForProjectAndLayout(
-            project, layout),
-        VariablesContainersList::
-            MakeNewVariablesContainersListForProjectAndLayout(project, layout),
-        PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
-
-    return projectScopedContainers;
-  }
+                                                    const gd::Layout &layout);
 
   static ProjectScopedContainers
-  MakeNewProjectScopedContainersForProject(const gd::Project &project) {
-    ProjectScopedContainers projectScopedContainers(
-        ObjectsContainersList::MakeNewObjectsContainersListForProject(
-            project),
-        VariablesContainersList::
-            MakeNewVariablesContainersListForProject(project),
-        PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
-
-    return projectScopedContainers;
-  }
+  MakeNewProjectScopedContainersForProject(const gd::Project &project);
 
   /**
    * @deprecated Use another method for an explicit context instead.
    */
   static ProjectScopedContainers MakeNewProjectScopedContainersFor(
       const gd::ObjectsContainer &globalObjectsContainers,
-      const gd::ObjectsContainer &objectsContainers) {
-    ProjectScopedContainers projectScopedContainers(
-        ObjectsContainersList::MakeNewObjectsContainersListForContainers(
-            globalObjectsContainers, objectsContainers),
-        VariablesContainersList::MakeNewEmptyVariablesContainersList(),
-        PropertiesContainersList::MakeNewEmptyPropertiesContainersList());
-
-    return projectScopedContainers;
-  };
+      const gd::ObjectsContainer &objectsContainers);
 
   static ProjectScopedContainers
   MakeNewProjectScopedContainersForEventsFunctionsExtension(
@@ -221,6 +197,24 @@ class ProjectScopedContainers {
     return variablesContainersList;
   };
 
+  /**
+   * @brief Return the global variables of the current scene or the current
+   * extension. It allows legacy "globalvar" parameters to accept extension
+   * variables.
+   */
+  const gd::VariablesContainer *GetLegacyGlobalVariables() const {
+    return legacyGlobalVariables;
+  };
+
+  /**
+   * @brief Return the scene variables of the current scene or the current
+   * extension. It allows legacy "scenevar" parameters to accept extension
+   * variables.
+   */
+  const gd::VariablesContainer *GetLegacySceneVariables() const {
+    return legacySceneVariables;
+  };
+
   const gd::PropertiesContainersList &GetPropertiesContainersList() const {
     return propertiesContainersList;
   };
@@ -231,11 +225,14 @@ class ProjectScopedContainers {
 
   /** Do not use - should be private but accessible to let Emscripten create a
    * temporary. */
-  ProjectScopedContainers(){};
+  ProjectScopedContainers()
+      : legacyGlobalVariables(nullptr), legacySceneVariables(nullptr){};
 
- private:
+private:
   gd::ObjectsContainersList objectsContainersList;
   gd::VariablesContainersList variablesContainersList;
+  const gd::VariablesContainer *legacyGlobalVariables;
+  const gd::VariablesContainer *legacySceneVariables;
   gd::PropertiesContainersList propertiesContainersList;
   std::vector<const ParameterMetadataContainer *> parametersVectorsList;
 };

Core/GDCore/Project/ResourcesManager.cpp

@@ -173,9 +173,6 @@ std::map<gd::String, gd::PropertyDescriptor> ImageResource::GetProperties()
   properties[_("Smooth the image")]
       .SetValue(smooth ? "true" : "false")
       .SetType("Boolean");
-  properties[_("Always loaded in memory")]
-      .SetValue(alwaysLoaded ? "true" : "false")
-      .SetType("Boolean");
 
   return properties;
 }
@@ -184,8 +181,6 @@ bool ImageResource::UpdateProperty(const gd::String& name,
                                    const gd::String& value) {
   if (name == _("Smooth the image"))
     smooth = value == "1";
-  else if (name == _("Always loaded in memory"))
-    alwaysLoaded = value == "1";
 
   return true;
 }
@@ -569,14 +564,12 @@ void ImageResource::SetFile(const gd::String& newFile) {
 }
 
 void ImageResource::UnserializeFrom(const SerializerElement& element) {
-  alwaysLoaded = element.GetBoolAttribute("alwaysLoaded");
   smooth = element.GetBoolAttribute("smoothed");
   SetUserAdded(element.GetBoolAttribute("userAdded"));
   SetFile(element.GetStringAttribute("file"));
 }
 
 void ImageResource::SerializeTo(SerializerElement& element) const {
-  element.SetAttribute("alwaysLoaded", alwaysLoaded);
   element.SetAttribute("smoothed", smooth);
   element.SetAttribute("userAdded", IsUserAdded());
   element.SetAttribute("file", GetFile());

Core/GDCore/Project/ResourcesManager.h

@@ -152,8 +152,8 @@ class GD_CORE_API Resource {
   gd::String metadata;
   gd::String originName;
   gd::String originIdentifier;
-  bool userAdded;  ///< True if the resource was added by the user, and not
-                   ///< automatically by GDevelop.
+  bool userAdded = false;  ///< True if the resource was added by the user, and not
+                           ///< automatically by GDevelop.
 
   static gd::String badStr;
 };
@@ -166,7 +166,7 @@ class GD_CORE_API Resource {
  */
 class GD_CORE_API ImageResource : public Resource {
  public:
-  ImageResource() : Resource(), smooth(true), alwaysLoaded(false) {
+  ImageResource() : Resource(), smooth(true) {
     SetKind("image");
   };
   virtual ~ImageResource(){};
@@ -210,7 +210,6 @@ class GD_CORE_API ImageResource : public Resource {
   void SetSmooth(bool enable = true) { smooth = enable; }
 
   bool smooth;        ///< True if smoothing filter is applied
-  bool alwaysLoaded;  ///< True if the image must always be loaded in memory.
  private:
   gd::String file;
 };

Core/GDCore/Project/Variable.h

@@ -33,7 +33,7 @@ class GD_CORE_API Variable {
     Unknown,
     /** Used when objects of a group have different types for a variable. */
     MixedTypes,
-    
+
     // Primitive types
     String,
     Number,
@@ -393,11 +393,11 @@ class GD_CORE_API Variable {
    */
   static Type StringAsType(const gd::String& str);
 
-  bool folded;
+  bool folded = false;
   mutable Type type;
   mutable gd::String str;
   mutable double value;
-  mutable bool boolVal;
+  mutable bool boolVal = false;
   mutable bool hasMixedValues;
   mutable std::map<gd::String, std::shared_ptr<Variable>>
       children;  ///< Children, when the variable is considered as a structure.

Core/GDCore/Project/VariablesContainer.h

@@ -187,7 +187,7 @@ class GD_CORE_API VariablesContainer {
   ///@}
 
  private:
-  SourceType sourceType;
+  SourceType sourceType = Unknown;
   std::vector<std::pair<gd::String, std::shared_ptr<gd::Variable>>> variables;
   mutable gd::String persistentUuid;  ///< A persistent random version 4 UUID,
                                       ///< useful for computing changesets.

Core/GDCore/Serialization/SerializerElement.h

@@ -456,13 +456,13 @@ class GD_CORE_API SerializerElement {
    */
   void Init(const gd::SerializerElement &other);
 
-  bool valueUndefined;  ///< If true, the element does not have a value.
+  bool valueUndefined = true;  ///< If true, the element does not have a value.
   SerializerValue elementValue;
 
   std::map<gd::String, SerializerValue> attributes;
   std::vector<std::pair<gd::String, std::shared_ptr<SerializerElement> > >
       children;
-  mutable bool isArray;        ///< true if element is considered as an array
+  mutable bool isArray = false;  ///< true if element is considered as an array
   mutable gd::String arrayOf;  ///< The name of the children (was useful for XML
                                ///< parsed elements).
   mutable gd::String deprecatedArrayOf;  ///< Alternate name for children

Core/GDCore/Serialization/rapidjson/.clang-tidy

@@ -0,0 +1,2 @@
+# Disable all checks in this folder.
+Checks: '-*'

Core/GDCore/String.cpp

@@ -4,6 +4,8 @@
  * This project is released under the MIT License.
  */
 
+// NOLINTBEGIN
+
 #include "GDCore/String.h"
 
 #include <algorithm>
@@ -825,3 +827,5 @@ bool GD_CORE_API CaseInsensitiveEquiv( const String &lhs, const String &rhs, boo
 }
 
 }
+
+// NOLINTEND

Core/GDCore/String.h

@@ -4,6 +4,8 @@
  * This project is released under the MIT License.
  */
 
+// NOLINTBEGIN
+
 #ifndef GDCORE_UTF8_STRING_H
 #define GDCORE_UTF8_STRING_H
 
@@ -898,3 +900,5 @@ namespace std
  * In Unicode, uppercasing/lowercasing strings to compare them in a case-insensitive way is not recommended.
  * That's why the function gd::CaseInsensitiveEquiv exists to compare two strings in a case-insensitive way.
  */
+
+// NOLINTEND

Core/GDCore/Tools/PolymorphicClone.h

@@ -2,6 +2,7 @@
 #define GD_CORE_POLYMORPHICCLONE_H
 
 #include <memory>
+#include <vector>
 
 namespace gd {
 

Core/GDCore/Tools/SerializableWithNameList.inl

@@ -3,6 +3,7 @@
  * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
  * reserved. This project is released under the MIT License.
  */
+#include <algorithm>
 #include "GDCore/Serialization/SerializerElement.h"
 #include "GDCore/String.h"
 #include "GDCore/Tools/MakeUnique.h"

Core/GDCore/Tools/SystemStats.cpp

@@ -3,6 +3,9 @@
  * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
  * reserved. This project is released under the MIT License.
  */
+
+// NOLINTBEGIN
+
 #include "SystemStats.h"
 #include "stdio.h"
 #include "stdlib.h"
@@ -49,3 +52,5 @@ size_t SystemStats::GetUsedVirtualMemory() {
 }
 
 }  // namespace gd
+
+// NOLINTEND

Core/GDCore/Tools/UUID/.clang-tidy

@@ -0,0 +1,2 @@
+# Disable all checks in this folder.
+Checks: '-*'

Core/GDCore/Utf8/.clang-tidy

@@ -0,0 +1,2 @@
+# Disable all checks in this folder.
+Checks: '-*'

Core/tests/ArbitraryResourceWorker.cpp

@@ -151,6 +151,37 @@ TEST_CASE("ArbitraryResourceWorker", "[common][resources]") {
       REQUIRE(worker.images[0] == "res1");
     }
 
+    SECTION("Can find resource usages in behavior configurations") {
+      gd::Platform platform;
+      gd::Project project;
+      SetupProjectWithDummyPlatform(project, platform);
+
+      project.GetResourcesManager().AddResource(
+          "res1", "path/to/file1.png", "image");
+      project.GetResourcesManager().AddResource(
+          "res2", "path/to/file2.png", "image");
+      project.GetResourcesManager().AddResource(
+          "res3", "path/to/file3.png", "image");
+      project.GetResourcesManager().AddResource(
+          "res4", "path/to/file4.png", "audio");
+      ArbitraryResourceWorkerTest worker(project.GetResourcesManager());
+
+      auto &layout = project.InsertNewLayout("Scene", 0);
+      auto &object = layout.GetObjects().InsertNewObject(
+          project, "MyExtension::Sprite", "MyObject", 0);
+      auto *behavior = object.AddNewBehavior(
+          project, "MyExtension::BehaviorWithRequiredBehaviorProperty",
+          "BehaviorWithResource");
+      behavior->UpdateProperty("resourceProperty", "res1");
+
+      worker.files.clear();
+      worker.images.clear();
+      gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
+      REQUIRE(worker.files.size() == 4);
+      REQUIRE(worker.images.size() == 1);
+      REQUIRE(worker.images[0] == "res1");
+    }
+
     SECTION("Can find resource usages in layout events") {
       gd::Platform platform;
       gd::Project project;

Core/tests/DummyPlatform.cpp

@@ -39,20 +39,31 @@ class BehaviorWithRequiredBehaviorProperty : public gd::Behavior {
             behaviorContent.GetStringAttribute("requiredBehaviorProperty"))
         .SetType("Behavior")
         .AddExtraInfo("MyExtension::MyBehavior");
+    properties["resourceProperty"]
+        .SetLabel("A resource")
+        .SetValue(
+            behaviorContent.GetStringAttribute("resourceProperty"))
+        .SetType("Resource")
+        .AddExtraInfo("image");
     return properties;
   }
   virtual bool UpdateProperty(gd::SerializerElement& behaviorContent,
                               const gd::String& name,
                               const gd::String& value) override {
-    if (name == _("requiredBehaviorProperty")) {
+    if (name == "requiredBehaviorProperty") {
       behaviorContent.SetAttribute("requiredBehaviorProperty", value);
       return true;
     }
+    if (name == "resourceProperty") {
+      behaviorContent.SetAttribute("resourceProperty", value);
+      return true;
+    }
     return false;
   }
   virtual void InitializeContent(
       gd::SerializerElement& behaviorContent) override {
     behaviorContent.SetAttribute("requiredBehaviorProperty", "");
+    behaviorContent.SetAttribute("resourceProperty", "");
   }
 };
 
@@ -254,9 +265,9 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
 
   extension
       ->AddAction("SetNumberVariable",
-                  "Do something with number variables",
-                  "This does something with variables",
-                  "Do something with variables",
+                  "Change variable value",
+                  "Modify the number value of a variable.",
+                  "the variable _PARAM0_",
                   "",
                   "",
                   "")
@@ -267,9 +278,9 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
 
   extension
       ->AddAction("SetStringVariable",
-                  "Do something with string variables",
-                  "This does something with variables",
-                  "Do something with variables",
+                  "Change text variable",
+                  "Modify the text (string) of a variable.",
+                  "the variable _PARAM0_",
                   "",
                   "",
                   "")
@@ -280,9 +291,9 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
 
   extension
       ->AddAction("SetBooleanVariable",
-                  "Do something with boolean variables",
-                  "This does something with variables",
-                  "Do something with variables",
+                  "Change boolean variable",
+                  "Modify the boolean value of a variable.",
+                  "Change the variable _PARAM0_: _PARAM1_",
                   "",
                   "",
                   "")
@@ -347,6 +358,17 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
       .AddParameter("soundfile", "Parameter 3 (an audio resource)")
       .SetFunctionName("doSomethingWithResources");
 
+  extension
+      ->AddAction("DoSomethingWithAnyVariable",
+                  "Do something with variables",
+                  "This does something with variables",
+                  "Do something with variables please",
+                  "",
+                  "",
+                  "")
+      .AddParameter("variable", "Any variable")
+      .SetFunctionName("doSomethingWithAnyVariable");
+
   extension
       ->AddAction("DoSomethingWithLegacyPreScopedVariables",
                   "Do something with variables",
@@ -687,6 +709,14 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
       .SetDefaultValue("\"\"")
       .AddParameter("layerEffectName", _("Effect name"))
       .AddParameter("layerEffectParameterName", _("Property name"));
+
+  extension
+      ->AddAction("DisplayLeaderboard",
+                  "Display leaderboard",
+                  "Display the specified leaderboard on top of the game.",
+                  "Display leaderboard _PARAM1_",
+                  "Display leaderboard", "", "")
+      .AddParameter("leaderboardId", "Leaderboard", "", false);
   }
 
   {

Core/tests/ExpressionParser2.cpp

@@ -1737,10 +1737,12 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
 
       gd::ExpressionValidator validator(platform, projectScopedContainers, "number|string");
       node->Visit(validator);
-      REQUIRE(validator.GetFatalErrors().size() == 2);
+      REQUIRE(validator.GetFatalErrors().size() == 3);
       REQUIRE(validator.GetFatalErrors()[0]->GetMessage() ==
               "A name should be entered after the dot.");
       REQUIRE(validator.GetFatalErrors()[1]->GetMessage() ==
+              "An object variable or expression should be entered.");
+      REQUIRE(validator.GetFatalErrors()[2]->GetMessage() ==
               "A name should be entered after the dot.");
     }
   }
@@ -1817,6 +1819,19 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
     }
   }
 
+  SECTION("Invalid object variables (non existing variable with child)") {
+    {
+      auto node =
+          parser.ParseExpression("MySpriteObject.MyNonExistingVariable.MyNonExistingChild");
+
+      gd::ExpressionValidator validator(platform, projectScopedContainers, "number|string");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 1);
+      REQUIRE(validator.GetFatalErrors()[0]->GetMessage() ==
+              "This variable does not exist on this object or group.");
+    }
+  }
+
   SECTION("Invalid object (object entered without any variable)") {
     {
       auto node =
@@ -1962,6 +1977,25 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
     }
   }
 
+  SECTION("Invalid property (required behavior)") {
+    {
+      gd::PropertiesContainer propertiesContainer(gd::EventsFunctionsContainer::Extension);
+
+      auto projectScopedContainersWithProperties = gd::ProjectScopedContainers::MakeNewProjectScopedContainersForProjectAndLayout(project, layout1);
+      projectScopedContainersWithProperties.AddPropertiesContainer(propertiesContainer);
+
+      propertiesContainer.InsertNew("MyRequiredBehavior").SetType("Behavior");
+
+      auto node =
+          parser.ParseExpression("\"abc\" + MyRequiredBehavior");
+
+      gd::ExpressionValidator validator(platform, projectScopedContainersWithProperties, "number|string");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 1);
+      REQUIRE(validator.GetFatalErrors()[0]->GetMessage() == "Behaviors can't be used as a value in expressions.");
+    }
+  }
+
   SECTION("Invalid property (unsupported child syntax, 1 level)") {
     {
       gd::PropertiesContainer propertiesContainer(gd::EventsFunctionsContainer::Extension);
@@ -2357,10 +2391,12 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
 
     gd::ExpressionValidator validator(platform, projectScopedContainers, "number");
     node->Visit(validator);
-    REQUIRE(validator.GetFatalErrors().size() == 2);
+    REQUIRE(validator.GetFatalErrors().size() == 3);
     REQUIRE(validator.GetFatalErrors()[0]->GetMessage() ==
           "A name should be entered after the dot.");
     REQUIRE(validator.GetFatalErrors()[1]->GetMessage() ==
+          "An object variable or expression should be entered.");
+    REQUIRE(validator.GetFatalErrors()[2]->GetMessage() ==
           "A name should be entered after the dot.");
   }
 

Core/tests/ObjectSerialization.cpp

@@ -262,4 +262,153 @@ TEST_CASE("ObjectSerialization", "[common]") {
     auto &behaviorElement = behaviorsElement.GetChild(0);
     REQUIRE(behaviorElement.GetStringAttribute("name") == "MyBehavior");
   }
-}
+
+  // Event-based object dependency cycles are not tested because they are forbidden by the editor.
+  SECTION("Save and load a project with custom object dependencies from different extensions") {
+    gd::Platform platform;
+    gd::Project writtenProject;
+    SetupProjectWithDummyPlatform(writtenProject, platform);
+
+    {
+      // The extension with the dependency is added first to make the
+      // implementation change the order in which extensions are loaded.
+      auto &eventsExtensionWithDependency =
+          writtenProject.InsertNewEventsFunctionsExtension(
+              "MyEventsExtensionWithDependency", 0);
+      auto &eventsExtension = writtenProject.InsertNewEventsFunctionsExtension(
+          "MyEventsExtension", 1);
+      {
+        auto &eventsBasedObject =
+            eventsExtension.GetEventsBasedObjects().InsertNew(
+                "MyEventsBasedObject", 0);
+        auto &childObject = eventsBasedObject.GetObjects().InsertNewObject(
+            writtenProject, "MyExtension::Sprite", "MyChildSprite", 0);
+      }
+      // An event-based object with a custom object child that overrides its
+      // configuration.
+      {
+        auto &eventsBasedObject =
+            eventsExtensionWithDependency.GetEventsBasedObjects().InsertNew(
+                "MyEventsBasedObjectWithDependency", 0);
+        auto &childObject = eventsBasedObject.GetObjects().InsertNewObject(
+            writtenProject, "MyEventsExtension::MyEventsBasedObject",
+            "MyChildCustomObject", 0);
+        auto *customObjectConfiguration =
+            dynamic_cast<gd::CustomObjectConfiguration *>(
+                &childObject.GetConfiguration());
+        auto &spriteConfiguration =
+            customObjectConfiguration->GetChildObjectConfiguration(
+                "MyChildSprite");
+        SetupSpriteConfiguration(spriteConfiguration);
+      }
+    }
+
+    SerializerElement projectElement;
+    writtenProject.SerializeTo(projectElement);
+
+    gd::Project readProject;
+    readProject.AddPlatform(platform);
+    readProject.UnserializeFrom(projectElement);
+
+    REQUIRE(readProject.GetEventsFunctionsExtensionsCount() == 2);
+    auto &eventsExtensionWithDependency =
+        readProject.GetEventsFunctionsExtension(0);
+    REQUIRE(eventsExtensionWithDependency.GetEventsBasedObjects().GetCount() ==
+            1);
+    auto &eventsBasedObject =
+        eventsExtensionWithDependency.GetEventsBasedObjects().Get(0);
+    REQUIRE(eventsBasedObject.GetObjects().GetObjectsCount() == 1);
+    auto &childObject = eventsBasedObject.GetObjects().GetObject(0);
+    REQUIRE(childObject.GetName() == "MyChildCustomObject");
+    REQUIRE(childObject.GetType() == "MyEventsExtension::MyEventsBasedObject");
+    auto *customObjectConfiguration =
+        dynamic_cast<gd::CustomObjectConfiguration *>(
+            &childObject.GetConfiguration());
+    REQUIRE(customObjectConfiguration != nullptr);
+    auto &spriteConfiguration =
+        customObjectConfiguration->GetChildObjectConfiguration("MyChildSprite");
+    CheckSpriteConfiguration(spriteConfiguration);
+  }
+
+  SECTION("Save and load a project with custom object dependencies inside an extension") {
+    gd::Platform platform;
+    gd::Project writtenProject;
+    SetupProjectWithDummyPlatform(writtenProject, platform);
+
+    {
+      auto &eventsExtension = writtenProject.InsertNewEventsFunctionsExtension(
+          "MyEventsExtension", 0);
+      {
+        auto &eventsBasedObject =
+            eventsExtension.GetEventsBasedObjects().InsertNew(
+                "MyEventsBasedObject", 0);
+        auto &childObject = eventsBasedObject.GetObjects().InsertNewObject(
+            writtenProject, "MyExtension::Sprite", "MyChildSprite", 0);
+      }
+      // An event-based object with a custom object child that overrides its
+      // configuration.
+      // The extension with the dependency is added first to make the
+      // implementation change the order in which extensions are loaded.
+      {
+        auto &eventsBasedObject =
+            eventsExtension.GetEventsBasedObjects().InsertNew(
+                "MyEventsBasedObjectWithDependency", 0);
+        auto &childObject = eventsBasedObject.GetObjects().InsertNewObject(
+            writtenProject, "MyEventsExtension::MyEventsBasedObject",
+            "MyChildCustomObject", 0);
+        auto *customObjectConfiguration =
+            dynamic_cast<gd::CustomObjectConfiguration *>(
+                &childObject.GetConfiguration());
+        auto &spriteConfiguration =
+            customObjectConfiguration->GetChildObjectConfiguration(
+                "MyChildSprite");
+        SetupSpriteConfiguration(spriteConfiguration);
+      }
+    }
+
+    SerializerElement projectElement;
+    writtenProject.SerializeTo(projectElement);
+
+    gd::Project readProject;
+    readProject.AddPlatform(platform);
+    readProject.UnserializeFrom(projectElement);
+
+    REQUIRE(readProject.GetEventsFunctionsExtensionsCount() == 1);
+    auto &eventsExtension =
+        readProject.GetEventsFunctionsExtension(0);
+    REQUIRE(eventsExtension.GetEventsBasedObjects().GetCount() == 2);
+    auto &eventsBasedObject =
+        eventsExtension.GetEventsBasedObjects().Get(0);
+    REQUIRE(eventsBasedObject.GetObjects().GetObjectsCount() == 1);
+    auto &childObject = eventsBasedObject.GetObjects().GetObject(0);
+    REQUIRE(childObject.GetName() == "MyChildCustomObject");
+    REQUIRE(childObject.GetType() == "MyEventsExtension::MyEventsBasedObject");
+    auto *customObjectConfiguration =
+        dynamic_cast<gd::CustomObjectConfiguration *>(
+            &childObject.GetConfiguration());
+    REQUIRE(customObjectConfiguration != nullptr);
+    auto &spriteConfiguration =
+        customObjectConfiguration->GetChildObjectConfiguration("MyChildSprite");
+    CheckSpriteConfiguration(spriteConfiguration);
+  }
+
+  SECTION("Can unserialize over an existing extension without duplicating its event-based objects") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    auto &eventsExtension =
+        project.InsertNewEventsFunctionsExtension("MyEventsExtension", 0);
+    {
+      auto &eventsBasedObject =
+          eventsExtension.GetEventsBasedObjects().InsertNew(
+              "MyEventsBasedObject", 0);
+    }
+
+    SerializerElement extensionElement;
+    eventsExtension.SerializeTo(extensionElement);
+    eventsExtension.UnserializeFrom(project, extensionElement);
+
+    REQUIRE(eventsExtension.GetEventsBasedObjects().GetCount() == 1);
+  }
+}

Core/tests/Project-EnsureObjectDefaultBehaviors.cpp

@@ -0,0 +1,74 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+/**
+ * @file Tests covering common features of GDevelop Core.
+ */
+#include "GDCore/Project/Project.h"
+
+#include <algorithm>
+
+#include "DummyPlatform.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Extensions/Platform.h"
+#include "GDCore/Extensions/PlatformExtension.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/String.h"
+#include "catch.hpp"
+
+TEST_CASE("Project::EnsureObjectDefaultBehaviors", "[common]") {
+  SECTION("Check that default behaviors are added to an object") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    auto myObject = project.CreateObject("MyExtension::Sprite", "MyObject");
+    REQUIRE(myObject->GetType() == "MyExtension::Sprite");
+    REQUIRE(myObject->GetAllBehaviorNames().size() == 0);
+
+    project.EnsureObjectDefaultBehaviors(*myObject);
+    REQUIRE(myObject->GetAllBehaviorNames().size() == 0);
+
+    // Modify the "Sprite" extension to add a default behavior to the object.
+    const auto& allExtensions = platform.GetAllPlatformExtensions();
+    auto spriteExtensionIt = std::find_if(
+        allExtensions.begin(),
+        allExtensions.end(),
+        [&](const std::shared_ptr<gd::PlatformExtension>& extension) {
+          return extension->GetName() == "MyExtension";
+        });
+    REQUIRE(spriteExtensionIt != allExtensions.end());
+    auto spriteExtension = *spriteExtensionIt;
+
+    auto& spriteObjectMetadata =
+        spriteExtension->GetObjectMetadata("MyExtension::Sprite");
+    REQUIRE(gd::MetadataProvider::IsBadObjectMetadata(spriteObjectMetadata) ==
+            false);
+
+    spriteObjectMetadata.AddDefaultBehavior(
+        "FlippableCapability::FlippableBehavior");
+
+    // Ensure the default behavior is added.
+    project.EnsureObjectDefaultBehaviors(*myObject);
+    REQUIRE(myObject->GetAllBehaviorNames().size() == 1);
+    REQUIRE(myObject->GetAllBehaviorNames()[0] == "Flippable");
+    REQUIRE(myObject->GetBehavior("Flippable").GetTypeName() == "FlippableCapability::FlippableBehavior");
+
+    // Ensure default behaviors are adapted if the object default behaviors are modified.
+    // While this can not happen with pre-coded extensions, it can happen with custom objects.
+    spriteObjectMetadata.ResetDefaultBehaviorsJustForTesting();
+    spriteObjectMetadata.AddDefaultBehavior(
+        "ResizableCapability::ResizableBehavior");
+    spriteObjectMetadata.AddDefaultBehavior(
+        "ScalableCapability::ScalableBehavior");
+
+    project.EnsureObjectDefaultBehaviors(*myObject);
+    REQUIRE(myObject->GetAllBehaviorNames().size() == 2);
+    REQUIRE(myObject->GetAllBehaviorNames()[0] == "Resizable");
+    REQUIRE(myObject->GetAllBehaviorNames()[1] == "Scale");
+    REQUIRE(myObject->GetBehavior("Resizable").GetTypeName() == "ResizableCapability::ResizableBehavior");
+    REQUIRE(myObject->GetBehavior("Scale").GetTypeName() == "ScalableCapability::ScalableBehavior");
+  }
+}

Core/tests/WholeProjectRefactorer.cpp

@@ -77,6 +77,34 @@ const gd::String &GetEventFirstActionType(const gd::BaseEvent &event) {
   return actions.Get(0).GetType();
 }
 
+const gd::Instruction &
+CreateInstructionWithNumberParameter(gd::Project &project,
+                                     gd::EventsList &events,
+                                     const gd::String &expression) {
+  gd::StandardEvent &event = dynamic_cast<gd::StandardEvent &>(
+      events.InsertNewEvent(project, "BuiltinCommonInstructions::Standard"));
+
+  gd::Instruction instruction;
+  instruction.SetType("MyExtension::DoSomething");
+  instruction.SetParametersCount(1);
+  instruction.SetParameter(0, expression);
+  return event.GetActions().Insert(instruction);
+}
+
+const gd::Instruction &
+CreateInstructionWithVariableParameter(gd::Project &project,
+                                     gd::EventsList &events,
+                                     const gd::String &expression) {
+  gd::StandardEvent &event = dynamic_cast<gd::StandardEvent &>(
+      events.InsertNewEvent(project, "BuiltinCommonInstructions::Standard"));
+
+  gd::Instruction instruction;
+  instruction.SetType("MyExtension::DoSomethingWithAnyVariable");
+  instruction.SetParametersCount(1);
+  instruction.SetParameter(0, expression);
+  return event.GetActions().Insert(instruction);
+}
+
 enum TestEvent {
   FreeFunctionAction,
   FreeFunctionWithExpression,
@@ -1533,7 +1561,8 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
       // events in this test.
 
       // Create the objects container for the events function
-      gd::ObjectsContainer parametersObjectsContainer;
+      gd::ObjectsContainer parametersObjectsContainer(
+          gd::ObjectsContainer::SourceType::Function);
       auto projectScopedContainers = gd::ProjectScopedContainers::
           MakeNewProjectScopedContainersForFreeEventsFunction(
               project, eventsExtension, eventsFunction,
@@ -1561,7 +1590,8 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
           eventsExtension.GetEventsFunction("MyOtherEventsFunction");
 
       // Create the objects container for the events function
-      gd::ObjectsContainer parametersObjectsContainer;
+      gd::ObjectsContainer parametersObjectsContainer(
+          gd::ObjectsContainer::SourceType::Function);
       auto projectScopedContainers = gd::ProjectScopedContainers::
           MakeNewProjectScopedContainersForFreeEventsFunction(
               project, eventsExtension, eventsFunction,
@@ -1616,7 +1646,8 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
           project, "MyExtension::Sprite", "Object2", 0);
 
       // Create the objects container for the events function
-      gd::ObjectsContainer parametersObjectsContainer;
+      gd::ObjectsContainer parametersObjectsContainer(
+          gd::ObjectsContainer::SourceType::Function);
       auto projectScopedContainers = gd::ProjectScopedContainers::
           MakeNewProjectScopedContainersForEventsBasedObject(
               project, eventsExtension, eventsBasedObject,
@@ -1657,7 +1688,8 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
       eventsBasedObject.GetInitialInstances().InsertInitialInstance(instance2);
 
       // Create the objects container for the events function
-      gd::ObjectsContainer parametersObjectsContainer;
+      gd::ObjectsContainer parametersObjectsContainer(
+          gd::ObjectsContainer::SourceType::Function);
       auto projectScopedContainers = gd::ProjectScopedContainers::
           MakeNewProjectScopedContainersForEventsBasedObject(
               project, eventsExtension, eventsBasedObject,
@@ -1683,7 +1715,8 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
               .Get("MyOtherEventsBasedObject");
 
       // Create the objects container for the events function
-      gd::ObjectsContainer parametersObjectsContainer;
+      gd::ObjectsContainer parametersObjectsContainer(
+          gd::ObjectsContainer::SourceType::Function);
       auto projectScopedContainers = gd::ProjectScopedContainers::
           MakeNewProjectScopedContainersForEventsBasedObject(
               project, eventsExtension, eventsBasedObject,
@@ -1738,7 +1771,8 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
           project, "MyExtension::Sprite", "Object2", 0);
 
       // Create the objects container for the events function
-      gd::ObjectsContainer parametersObjectsContainer;
+      gd::ObjectsContainer parametersObjectsContainer(
+          gd::ObjectsContainer::SourceType::Function);
       auto projectScopedContainers = gd::ProjectScopedContainers::
           MakeNewProjectScopedContainersForEventsBasedObject(
               project, eventsExtension, eventsBasedObject,
@@ -1778,7 +1812,8 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
       eventsBasedObject.GetInitialInstances().InsertInitialInstance(instance2);
 
       // Create the objects container for the events function
-      gd::ObjectsContainer parametersObjectsContainer;
+      gd::ObjectsContainer parametersObjectsContainer(
+          gd::ObjectsContainer::SourceType::Function);
       auto projectScopedContainers = gd::ProjectScopedContainers::
           MakeNewProjectScopedContainersForEventsBasedObject(
               project, eventsExtension, eventsBasedObject,
@@ -3038,6 +3073,66 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
     }
   }
 
+  SECTION("(Events based behavior) property renamed (in expressions)") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+    auto &eventsExtension = SetupProjectWithEventsFunctionExtension(project);
+    auto &eventsBasedBehavior =
+        eventsExtension.GetEventsBasedBehaviors().Get("MyEventsBasedBehavior");
+
+    auto &behaviorAction =
+        eventsBasedBehavior.GetEventsFunctions().InsertNewEventsFunction(
+            "MyBehaviorEventsFunction", 0);
+    gd::WholeProjectRefactorer::EnsureBehaviorEventsFunctionsProperParameters(
+        eventsExtension, eventsBasedBehavior);
+    auto &instruction = CreateInstructionWithNumberParameter(
+        project, behaviorAction.GetEvents(), "MyProperty");
+    auto &instruction2 = CreateInstructionWithNumberParameter(
+        project, behaviorAction.GetEvents(),
+        "MyExtension::GetVariableAsNumber(MyVariable.MyChild[MyProperty])");
+
+    gd::WholeProjectRefactorer::RenameEventsBasedBehaviorProperty(
+        project, eventsExtension, eventsBasedBehavior, "MyProperty",
+        "MyRenamedProperty");
+
+    REQUIRE(instruction.GetParameter(0).GetPlainString() ==
+            "MyRenamedProperty");
+    REQUIRE(instruction2.GetParameter(0).GetPlainString() ==
+            "MyExtension::GetVariableAsNumber(MyVariable.MyChild[MyRenamedProperty])");
+  }
+
+  SECTION("(Events based behavior) property not renamed (in variable parameter)") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+    auto &eventsExtension = SetupProjectWithEventsFunctionExtension(project);
+    auto &eventsBasedBehavior =
+        eventsExtension.GetEventsBasedBehaviors().Get("MyEventsBasedBehavior");
+
+    auto &behaviorAction =
+        eventsBasedBehavior.GetEventsFunctions().InsertNewEventsFunction(
+            "MyBehaviorEventsFunction", 0);
+    gd::WholeProjectRefactorer::EnsureBehaviorEventsFunctionsProperParameters(
+        eventsExtension, eventsBasedBehavior);
+    // Properties can't actually be used in "variable" parameters.
+    auto &instruction = CreateInstructionWithVariableParameter(
+        project, behaviorAction.GetEvents(), "MyProperty");
+    auto &instruction2 = CreateInstructionWithNumberParameter(
+        project, behaviorAction.GetEvents(),
+        "MyExtension::GetVariableAsNumber(MyProperty)");
+
+    gd::WholeProjectRefactorer::RenameEventsBasedBehaviorProperty(
+        project, eventsExtension, eventsBasedBehavior, "MyProperty",
+        "MyRenamedProperty");
+
+    // "variable" parameters are left untouched.
+    REQUIRE(instruction.GetParameter(0).GetPlainString() ==
+            "MyProperty");
+    REQUIRE(instruction2.GetParameter(0).GetPlainString() ==
+            "MyExtension::GetVariableAsNumber(MyProperty)");
+  }
+
   SECTION("(Events based behavior) shared property renamed") {
     gd::Project project;
     gd::Platform platform;
@@ -3089,6 +3184,35 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
     }
   }
 
+  SECTION("(Events based behavior) shared property renamed (in expressions)") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+    auto &eventsExtension = SetupProjectWithEventsFunctionExtension(project);
+    auto &eventsBasedBehavior =
+        eventsExtension.GetEventsBasedBehaviors().Get("MyEventsBasedBehavior");
+
+    auto &behaviorAction =
+        eventsBasedBehavior.GetEventsFunctions().InsertNewEventsFunction(
+            "MyBehaviorEventsFunction", 0);
+    gd::WholeProjectRefactorer::EnsureBehaviorEventsFunctionsProperParameters(
+        eventsExtension, eventsBasedBehavior);
+    auto &instruction = CreateInstructionWithNumberParameter(
+        project, behaviorAction.GetEvents(), "MySharedProperty");
+    auto &instruction2 = CreateInstructionWithNumberParameter(
+        project, behaviorAction.GetEvents(),
+        "MyExtension::GetVariableAsNumber(MyVariable.MyChild[MySharedProperty])");
+
+    gd::WholeProjectRefactorer::RenameEventsBasedBehaviorSharedProperty(
+        project, eventsExtension, eventsBasedBehavior, "MySharedProperty",
+        "MyRenamedSharedProperty");
+
+    REQUIRE(instruction.GetParameter(0).GetPlainString() ==
+            "MyRenamedSharedProperty");
+    REQUIRE(instruction2.GetParameter(0).GetPlainString() ==
+            "MyExtension::GetVariableAsNumber(MyVariable.MyChild[MyRenamedSharedProperty])");
+  }
+
   SECTION("(Events based object) property renamed") {
     gd::Project project;
     gd::Platform platform;
@@ -3118,6 +3242,66 @@ TEST_CASE("WholeProjectRefactorer", "[common]") {
               "MyCustomObject.PropertyMyRenamedProperty()");
     }
   }
+
+  SECTION("(Events based object) property renamed (in expressions)") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+    auto &eventsExtension = SetupProjectWithEventsFunctionExtension(project);
+    auto &eventsBasedObject =
+        eventsExtension.GetEventsBasedObjects().Get("MyEventsBasedObject");
+
+    auto &behaviorAction =
+        eventsBasedObject.GetEventsFunctions().InsertNewEventsFunction(
+            "MyObjectEventsFunction", 0);
+    gd::WholeProjectRefactorer::EnsureObjectEventsFunctionsProperParameters(
+        eventsExtension, eventsBasedObject);
+    auto &instruction = CreateInstructionWithNumberParameter(
+        project, behaviorAction.GetEvents(), "MyProperty");
+    auto &instruction2 = CreateInstructionWithNumberParameter(
+        project, behaviorAction.GetEvents(),
+        "MyExtension::GetVariableAsNumber(MyVariable.MyChild[MyProperty])");
+
+    gd::WholeProjectRefactorer::RenameEventsBasedObjectProperty(
+        project, eventsExtension, eventsBasedObject, "MyProperty",
+        "MyRenamedProperty");
+
+    REQUIRE(instruction.GetParameter(0).GetPlainString() ==
+            "MyRenamedProperty");
+    REQUIRE(instruction2.GetParameter(0).GetPlainString() ==
+            "MyExtension::GetVariableAsNumber(MyVariable.MyChild[MyRenamedProperty])");
+  }
+
+  SECTION("(Events based object) property not renamed (in variable parameter)") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+    auto &eventsExtension = SetupProjectWithEventsFunctionExtension(project);
+    auto &eventsBasedObject =
+        eventsExtension.GetEventsBasedObjects().Get("MyEventsBasedObject");
+
+    auto &behaviorAction =
+        eventsBasedObject.GetEventsFunctions().InsertNewEventsFunction(
+            "MyObjectEventsFunction", 0);
+    gd::WholeProjectRefactorer::EnsureObjectEventsFunctionsProperParameters(
+        eventsExtension, eventsBasedObject);
+    // Properties can't actually be used in "variable" parameters.
+    auto &instruction = CreateInstructionWithVariableParameter(
+        project, behaviorAction.GetEvents(), "MyProperty");
+    auto &instruction2 = CreateInstructionWithNumberParameter(
+        project, behaviorAction.GetEvents(),
+        "MyExtension::GetVariableAsNumber(MyProperty)");
+
+    gd::WholeProjectRefactorer::RenameEventsBasedObjectProperty(
+        project, eventsExtension, eventsBasedObject, "MyProperty",
+        "MyRenamedProperty");
+
+    // "variable" parameters are left untouched.
+    REQUIRE(instruction.GetParameter(0).GetPlainString() ==
+            "MyProperty");
+    REQUIRE(instruction2.GetParameter(0).GetPlainString() ==
+            "MyExtension::GetVariableAsNumber(MyProperty)");
+  }
 }
 // TODO: Check that this works when behaviors are attached to a child-object.
 TEST_CASE("WholeProjectRefactorer (FindInvalidRequiredBehaviorProperties)",
@@ -4451,4 +4635,33 @@ TEST_CASE("MergeLayers", "[common]") {
     // Other layers from the same layout are untouched.
     REQUIRE(initialInstances.GetLayerInstancesCount("My other layer") == 1);
   }
+
+  // TODO: ideally, a test should also cover objects having `leaderboardId` as property.
+  SECTION("Can rename a leaderboard in scene events") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    auto &layout = project.InsertNewLayout("My layout", 0);
+
+    gd::StandardEvent &event = dynamic_cast<gd::StandardEvent &>(
+        layout.GetEvents().InsertNewEvent(project, "BuiltinCommonInstructions::Standard"));
+
+    gd::Instruction action;
+    action.SetType("MyExtension::DisplayLeaderboard");
+    action.SetParametersCount(1);
+    action.SetParameter(0, gd::Expression("\"12345678-9abc-def0-1234-56789abcdef0\""));
+    event.GetActions().Insert(action);
+
+    std::set<gd::String> allLeaderboardIds = gd::WholeProjectRefactorer::FindAllLeaderboardIds(project);
+    REQUIRE(allLeaderboardIds.size() == 1);
+    REQUIRE(allLeaderboardIds.count("12345678-9abc-def0-1234-56789abcdef0") == 1);
+
+    std::map<gd::String, gd::String> leaderboardIdMap;
+    leaderboardIdMap["12345678-9abc-def0-1234-56789abcdef0"] = "87654321-9abc-def0-1234-56789abcdef0";
+    gd::WholeProjectRefactorer::RenameLeaderboards(project, leaderboardIdMap);
+
+    REQUIRE(GetEventFirstActionFirstParameterString(layout.GetEvents().GetEvent(0)) ==
+            "\"87654321-9abc-def0-1234-56789abcdef0\"");
+  }
 }

Extensions/3D/CustomRuntimeObject3D.ts

@@ -112,10 +112,25 @@ namespace gdjs {
      * @return The Z position of the rendered object.
      */
     getDrawableZ(): float {
-      if (this._isUntransformedHitBoxesDirty) {
-        this._updateUntransformedHitBoxes();
+      let minZ = 0;
+      if (this._innerArea) {
+        minZ = this._innerArea.min[2];
+      } else {
+        if (this._isUntransformedHitBoxesDirty) {
+          this._updateUntransformedHitBoxes();
+        }
+        minZ = this._minZ;
+      }
+      const absScaleZ = this.getScaleZ();
+      if (!this._flippedZ) {
+        return this._z + minZ * absScaleZ;
+      } else {
+        return (
+          this._z +
+          (-minZ - this.getUnscaledDepth() + 2 * this.getUnscaledCenterZ()) *
+            absScaleZ
+        );
       }
-      return this._z + this._minZ;
     }
 
     /**
@@ -238,10 +253,39 @@ namespace gdjs {
       this.setAngle(gdjs.toDegrees(mesh.rotation.z));
     }
 
+    /**
+     * @return the internal top bound of the object according to its children.
+     */
+    getInnerAreaMinZ(): number {
+      if (this._innerArea) {
+        return this._innerArea.min[2];
+      }
+      if (this._isUntransformedHitBoxesDirty) {
+        this._updateUntransformedHitBoxes();
+      }
+      return this._minZ;
+    }
+
+    /**
+     * @return the internal bottom bound of the object according to its children.
+     */
+    getInnerAreaMaxZ(): number {
+      if (this._innerArea) {
+        return this._innerArea.max[2];
+      }
+      if (this._isUntransformedHitBoxesDirty) {
+        this._updateUntransformedHitBoxes();
+      }
+      return this._maxZ;
+    }
+
     /**
      * @return the internal width of the object according to its children.
      */
     getUnscaledDepth(): float {
+      if (this._innerArea) {
+        return this._innerArea.max[2] - this._innerArea.min[2];
+      }
       if (this._isUntransformedHitBoxesDirty) {
         this._updateUntransformedHitBoxes();
       }
@@ -280,6 +324,9 @@ namespace gdjs {
       if (this.hasCustomRotationCenter()) {
         return this._customCenterZ;
       }
+      if (this._innerArea) {
+        return (this._innerArea.min[2] + this._innerArea.max[2]) / 2;
+      }
       if (this._isUntransformedHitBoxesDirty) {
         this._updateUntransformedHitBoxes();
       }

Extensions/3D/JsExtension.js

@@ -2203,6 +2203,8 @@ module.exports = {
           if (!texture.baseTexture.valid) {
             // Post pone texture update if texture is not loaded.
             texture.once('update', () => {
+              if (this._wasDestroyed) return;
+
               this.updateTexture();
               this.updatePIXISprite();
             });
@@ -2375,6 +2377,7 @@ module.exports = {
           getFaceMaterial(this._project, materialIndexToFaceIndex[4]),
           getFaceMaterial(this._project, materialIndexToFaceIndex[5]),
         ]);
+        if (this._wasDestroyed) return;
 
         this._threeObject.material[0] = materials[0];
         this._threeObject.material[1] = materials[1];
@@ -2823,6 +2826,7 @@ module.exports = {
         this._pixiResourcesLoader
           .get3DModel(project, modelResourceName)
           .then((model3d) => {
+            if (this._wasDestroyed) return;
             const clonedModel3D = THREE_ADDONS.SkeletonUtils.clone(
               model3d.scene
             );
@@ -3227,9 +3231,9 @@ module.exports = {
               : this._originalDepth / modelDepth;
           const minScaleRatio = Math.min(widthRatio, heightRatio, depthRatio);
           if (!Number.isFinite(minScaleRatio)) {
-            this._defaultWidth = modelWidth;
-            this._defaultHeight = modelHeight;
-            this._defaultDepth = modelDepth;
+            this._defaultWidth = this._originalWidth;
+            this._defaultHeight = this._originalHeight;
+            this._defaultDepth = this._originalDepth;
           } else {
             if (widthRatio === minScaleRatio) {
               this._defaultWidth = this._originalWidth;
@@ -3270,6 +3274,10 @@ module.exports = {
               this._defaultDepth = this._originalDepth;
             }
           }
+        } else {
+          this._defaultWidth = this._originalWidth;
+          this._defaultHeight = this._originalHeight;
+          this._defaultDepth = this._originalDepth;
         }
 
         this._threeObject.add(this._threeModelGroup);
@@ -3338,6 +3346,7 @@ module.exports = {
           this._pixiResourcesLoader
             .get3DModel(this._project, modelResourceName)
             .then((model3d) => {
+              if (this._wasDestroyed) return;
               this._clonedModel3D = THREE_ADDONS.SkeletonUtils.clone(
                 model3d.scene
               );

Extensions/AnchorBehavior/anchorruntimebehavior.ts

@@ -110,13 +110,15 @@ namespace gdjs {
         }
 
         //Calculate the distances from the window's bounds.
-        const topLeftPixel = this._convertCoords(
-          instanceContainer,
-          layer,
-          this.owner.getDrawableX(),
-          this.owner.getDrawableY(),
-          workingPoint
-        );
+        const topLeftPixel = this._relativeToOriginalWindowSize
+          ? [this.owner.getDrawableX(), this.owner.getDrawableY()]
+          : this._convertInverseCoords(
+              instanceContainer,
+              layer,
+              this.owner.getDrawableX(),
+              this.owner.getDrawableY(),
+              workingPoint
+            );
 
         // Left edge
         if (this._leftEdgeAnchor === HorizontalAnchor.WindowLeft) {
@@ -141,13 +143,18 @@ namespace gdjs {
         }
 
         // It's fine to reuse workingPoint as topLeftPixel is no longer used.
-        const bottomRightPixel = this._convertCoords(
-          instanceContainer,
-          layer,
-          this.owner.getDrawableX() + this.owner.getWidth(),
-          this.owner.getDrawableY() + this.owner.getHeight(),
-          workingPoint
-        );
+        const bottomRightPixel = this._relativeToOriginalWindowSize
+          ? [
+              this.owner.getDrawableX() + this.owner.getWidth(),
+              this.owner.getDrawableY() + this.owner.getHeight(),
+            ]
+          : this._convertInverseCoords(
+              instanceContainer,
+              layer,
+              this.owner.getDrawableX() + this.owner.getWidth(),
+              this.owner.getDrawableY() + this.owner.getHeight(),
+              workingPoint
+            );
 
         // Right edge
         if (this._rightEdgeAnchor === HorizontalAnchor.WindowLeft) {
@@ -226,17 +233,17 @@ namespace gdjs {
         }
 
         // It's fine to reuse workingPoint as topLeftPixel is no longer used.
-        const topLeftCoord = this._convertInverseCoords(
+        const topLeftCoord = this._convertCoords(
           instanceContainer,
           layer,
           leftPixel,
           topPixel,
           workingPoint
         );
-        const left = topLeftCoord[0];
-        const top = topLeftCoord[1];
+        let left = topLeftCoord[0];
+        let top = topLeftCoord[1];
 
-        const bottomRightCoord = this._convertInverseCoords(
+        const bottomRightCoord = this._convertCoords(
           instanceContainer,
           layer,
           rightPixel,

Extensions/BitmapText/JsExtension.js

@@ -697,6 +697,8 @@ module.exports = {
             this._currentBitmapFontResourceName,
             this._currentTextureAtlasResourceName
           ).then((bitmapFont) => {
+            if (this._wasDestroyed) return;
+
             this._pixiObject.fontName = bitmapFont.font;
             this._pixiObject.fontSize = bitmapFont.size;
             this._pixiObject.dirty = true;

Extensions/DialogueTree/JsExtension.js

@@ -34,18 +34,18 @@ module.exports = {
     extension
       .addAction(
         'LoadDialogueFromSceneVariable',
-        _('Load dialogue Tree from a scene variable'),
+        _('Load dialogue tree from a scene variable'),
         _(
-          'Load a dialogue data object - Yarn json format, stored in a scene variable. Use this command to load all the Dialogue data at the beginning of the game.'
+          'Load a dialogue data object - Yarn JSON format, stored in a scene variable. Use this command to load all the Dialogue data at the beginning of the game.'
         ),
-        _('Load dialogue data from Scene variable _PARAM0_'),
+        _('Load dialogue data from scene variable _PARAM0_'),
         '',
         'JsPlatform/Extensions/yarn32.png',
         'JsPlatform/Extensions/yarn32.png'
       )
       .addParameter(
         'scenevar',
-        _('Scene variable that holds the Yarn Json data'),
+        _('Scene variable that holds the Yarn JSON data'),
         '',
         false
       )
@@ -57,11 +57,11 @@ module.exports = {
     extension
       .addAction(
         'LoadDialogueFromJsonFile',
-        _('Load dialogue Tree from a Json File'),
+        _('Load dialogue tree from a JSON file'),
         _(
-          'Load a dialogue data object - Yarn json format, stored in a Json file. Use this command to load all the Dialogue data at the beginning of the game.'
+          'Load a dialogue data object - Yarn JSON format, stored in a JSON file. Use this command to load all the Dialogue data at the beginning of the game.'
         ),
-        _('Load dialogue data from json file _PARAM1_'),
+        _('Load dialogue data from JSON file _PARAM1_'),
         '',
         'JsPlatform/Extensions/yarn32.png',
         'JsPlatform/Extensions/yarn32.png'
@@ -69,7 +69,7 @@ module.exports = {
       .addCodeOnlyParameter('currentScene', '')
       .addParameter(
         'jsonResource',
-        _('Json file that holds the Yarn Json data'),
+        _('JSON file that holds the Yarn JSON data'),
         '',
         false
       )
@@ -125,11 +125,11 @@ module.exports = {
     extension
       .addAction(
         'ConfirmSelectOption',
-        _('Confirm selected Option'),
+        _('Confirm selected option'),
         _(
           'Set the selected option as confirmed, which will validate it and go forward to the next node. Use other actions to select options (see "select next option" and "Select previous option").'
         ),
-        _('Confirm selected Option'),
+        _('Confirm selected option'),
         '',
         'JsPlatform/Extensions/yarn32.png',
         'JsPlatform/Extensions/yarn32.png'
@@ -140,11 +140,11 @@ module.exports = {
     extension
       .addAction(
         'SelectNextOption',
-        _('Select next Option'),
+        _('Select next option'),
         _(
-          'Select next Option (add 1 to selected option number). Use this when the dialogue line is of type "options" and the player has pressed a button to change selected option.'
+          'Select next option (add 1 to selected option number). Use this when the dialogue line is of type "options" and the player has pressed a button to change selected option.'
         ),
-        _('Select next Option'),
+        _('Select next option'),
         '',
         'JsPlatform/Extensions/yarn32.png',
         'JsPlatform/Extensions/yarn32.png'
@@ -155,11 +155,11 @@ module.exports = {
     extension
       .addAction(
         'SelectPreviousOption',
-        _('Select previous Option'),
+        _('Select previous option'),
         _(
-          'Select previous Option (subtract 1 from selected option number). Use this when the dialogue line is of type "options" and the player has pressed a button to change selected option.'
+          'Select previous option (subtract 1 from selected option number). Use this when the dialogue line is of type "options" and the player has pressed a button to change selected option.'
         ),
-        _('Select previous Option'),
+        _('Select previous option'),
         '',
         'JsPlatform/Extensions/yarn32.png',
         'JsPlatform/Extensions/yarn32.png'
@@ -225,8 +225,8 @@ module.exports = {
         'JsPlatform/Extensions/yarn32.png',
         'JsPlatform/Extensions/yarn32.png'
       )
-      .addParameter('string', _('State Variable Name'), '', false)
-      .addParameter('string', _('Variable string value'), '', false)
+      .addParameter('string', _('State variable name'), '', false)
+      .addParameter('string', _('New value'), '', false)
       .getCodeExtraInformation()
       .setFunctionName('gdjs.dialogueTree.setVariable');
 
@@ -242,8 +242,8 @@ module.exports = {
         'JsPlatform/Extensions/yarn32.png',
         'JsPlatform/Extensions/yarn32.png'
       )
-      .addParameter('string', _('State Variable Name'), '', false)
-      .addParameter('expression', _('Variable number value'), '', true)
+      .addParameter('string', _('State variable name'), '', false)
+      .addParameter('expression', _('New value'), '', true)
       .getCodeExtraInformation()
       .setFunctionName('gdjs.dialogueTree.setVariable');
 
@@ -259,8 +259,8 @@ module.exports = {
         'JsPlatform/Extensions/yarn32.png',
         'JsPlatform/Extensions/yarn32.png'
       )
-      .addParameter('string', _('State Variable Name'), '', false)
-      .addParameter('trueorfalse', _('Variable boolean value'), '', false)
+      .addParameter('string', _('State variable name'), '', false)
+      .addParameter('trueorfalse', _('New value'), '', false)
       .getCodeExtraInformation()
       .setFunctionName('gdjs.dialogueTree.setVariable');
 
@@ -336,9 +336,9 @@ module.exports = {
     extension
       .addStrExpression(
         'Option',
-        _('Get the text of an option from an Options line type'),
+        _('Get the text of an option from an options line type'),
         _(
-          "Get the text of an option from an Options line type, using the option's Number. The numbers start from 0."
+          "Get the text of an option from an options line type, using the option's Number. The numbers start from 0."
         ),
         '',
         'JsPlatform/Extensions/yarn32.png'
@@ -350,9 +350,9 @@ module.exports = {
     extension
       .addStrExpression(
         'HorizontalOptionsList',
-        _('Get a Horizontal list of options from the Options line type'),
+        _('Get a Horizontal list of options from the options line type'),
         _(
-          "Get the text of all available options from an Options line type as a horizontal list. You can also pass the selected option's cursor string, which by default is ->"
+          "Get the text of all available options from an options line type as a horizontal list. You can also pass the selected option's cursor string, which by default is ->"
         ),
         '',
         'JsPlatform/Extensions/yarn32.png'
@@ -365,9 +365,9 @@ module.exports = {
     extension
       .addStrExpression(
         'VerticalOptionsList',
-        _('Get a Vertical list of options from the Options line type'),
+        _('Get a Vertical list of options from the options line type'),
         _(
-          "Get the text of all available options from an Options line type as a vertical list. You can also pass the selected option's cursor string, which by default is ->"
+          "Get the text of all available options from an options line type as a vertical list. You can also pass the selected option's cursor string, which by default is ->"
         ),
         '',
         'JsPlatform/Extensions/yarn32.png'
@@ -507,14 +507,26 @@ module.exports = {
     extension
       .addExpression(
         'Variable',
-        _('Get dialogue state value'),
-        _('Get dialogue state value'),
+        _('Get the number stored in a dialogue state variable'),
+        _('Get the number stored in a dialogue state variable'),
         '',
         'JsPlatform/Extensions/yarn32.png'
       )
-      .addParameter('string', _('Variable Name'), '', false)
+      .addParameter('string', _('Dialogue state variable name'), '', false)
       .getCodeExtraInformation()
-      .setFunctionName('gdjs.dialogueTree.getVariable');
+      .setFunctionName('gdjs.dialogueTree.getVariableAsNumber');
+
+    extension
+      .addStrExpression(
+        'VariableString',
+        _('Get the string stored in a dialogue state variable'),
+        _('Get the string stored in a dialogue state variable'),
+        '',
+        'JsPlatform/Extensions/yarn32.png'
+      )
+      .addParameter('string', _('Dialogue state variable name'), '', false)
+      .getCodeExtraInformation()
+      .setFunctionName('gdjs.dialogueTree.getVariableAsString');
 
     extension
       .addCondition(

Extensions/DialogueTree/dialoguetools.ts

@@ -362,7 +362,15 @@ namespace gdjs {
       this.commandCalls = [];
       try {
         this.dialogueData.select(this.selectedOption);
-        this.dialogueData = this.dialogue.next().value;
+        try {
+          this.dialogueData = this.dialogue.next().value;
+        } catch (error) {
+          logger.error(
+            'Error while confirming in the dialogue tree. Verify if there is a syntax error? Full error is: ',
+            error
+          );
+          return;
+        }
         gdjs.dialogueTree.goToNextDialogueLine();
       } catch (error) {
         logger.error(
@@ -511,13 +519,29 @@ namespace gdjs {
     this.optionsCount = 0;
     this.options = [];
     this.tagParameters = [];
-    this.dialogue = this.runner.run(startDialogueNode);
+    try {
+      this.dialogue = this.runner.run(startDialogueNode);
+    } catch (error) {
+      logger.error(
+        'Error while setting up the dialogue tree. Verify if there is a syntax error? Full error is: ',
+        error
+      );
+      return;
+    }
     this.dialogueText = '';
     this.clipTextEnd = 0;
     this.commandCalls = [];
     this.commandParameters = [];
     this.pauseScrolling = false;
-    this.dialogueData = this.dialogue.next().value;
+    try {
+      this.dialogueData = this.dialogue.next().value;
+    } catch (error) {
+      logger.error(
+        'Error while starting the dialogue tree. Verify if there is a syntax error? Full error is: ',
+        error
+      );
+      return;
+    }
     this.dialogueBranchTags = this.dialogueData.data.tags;
     this.dialogueBranchTitle = this.dialogueData.data.title;
     this.dialogueBranchBody = this.dialogueData.data.body;
@@ -583,7 +607,15 @@ namespace gdjs {
         this.dialogueBranchBody = this.dialogueData.data.body;
         this.lineNum = this.dialogueData.lineNum;
         this.dialogueDataType = 'text';
-        this.dialogueData = this.dialogue.next().value;
+        try {
+          this.dialogueData = this.dialogue.next().value;
+        } catch (error) {
+          logger.error(
+            'Error while progressing the dialogue tree. Verify if there is a syntax error? Full error is: ',
+            error
+          );
+          return;
+        }
       } else {
         if (gdjs.dialogueTree._isLineTypeOptions()) {
           this.commandCalls = [];
@@ -609,7 +641,15 @@ namespace gdjs {
               params: command,
               time: this.dialogueText.length + offsetTime,
             });
-            this.dialogueData = this.dialogue.next().value;
+            try {
+              this.dialogueData = this.dialogue.next().value;
+            } catch (error) {
+              logger.error(
+                'Error while progressing the dialogue tree. Verify if there is a syntax error? Full error is: ',
+                error
+              );
+              return;
+            }
             gdjs.dialogueTree.goToNextDialogueLine();
           } else {
             this.dialogueDataType = 'unknown';
@@ -734,16 +774,45 @@ namespace gdjs {
   };
 
   /**
-   * Get the value of a variable that was created by the Dialogue parses.
-   * @param key The name of the variable you want to get the value of
+   * Get the value of a variable stored in the dialogue state.
+   * @param key The variable name
    */
-  gdjs.dialogueTree.getVariable = function (key: string) {
+  gdjs.dialogueTree.getVariable = function (
+    key: string
+  ): string | float | boolean {
     if (this.runner.variables && key in this.runner.variables.data) {
       return this.runner.variables.get(key);
     }
     return '';
   };
 
+  /**
+   * Get the value of a variable stored in the dialogue state.
+   * @param key The variable name
+   */
+  gdjs.dialogueTree.getVariableAsNumber = function (key: string): float {
+    if (this.runner.variables && key in this.runner.variables.data) {
+      const value = this.runner.variables.get(key);
+      if (typeof value !== 'number') {
+        return parseFloat(value) || 0;
+      }
+
+      return isFinite(value) ? value : 0;
+    }
+    return 0;
+  };
+
+  /**
+   * Get the value of a variable stored in the dialogue state.
+   * @param key The variable name
+   */
+  gdjs.dialogueTree.getVariableAsString = function (key: string): string {
+    if (this.runner.variables && key in this.runner.variables.data) {
+      return '' + this.runner.variables.get(key);
+    }
+    return '';
+  };
+
   /**
    * Check if a specific variable created by the Dialogue parses exists and is equal to a specific value.
    * @param key The name of the variable you want to check the value of

Extensions/JsExtensionTypes.d.ts

@@ -14,9 +14,12 @@ class RenderedInstance {
   _associatedObjectConfiguration: gd.ObjectConfiguration;
   _pixiContainer: PIXI.Container;
   _pixiResourcesLoader: Class<PixiResourcesLoader>;
-  _pixiObject: PIXI.DisplayObject;
+  _pixiObject: PIXI.DisplayObject | null;
   wasUsed: boolean;
 
+  /** Set to true when onRemovedFromScene is called. Allows to cancel promises/asynchronous operations (notably: waiting for a resource load). */
+  _wasDestroyed: boolean;
+
   constructor(
     project: gdProject,
     instance: gdInitialInstance,
@@ -89,10 +92,13 @@ class Rendered3DInstance {
   _pixiContainer: PIXI.Container;
   _threeGroup: THREE.Group;
   _pixiResourcesLoader: Class<PixiResourcesLoader>;
-  _pixiObject: PIXI.DisplayObject;
+  _pixiObject: PIXI.DisplayObject | null;
   _threeObject: THREE.Object3D | null;
   wasUsed: boolean;
 
+  /** Set to true when onRemovedFromScene is called. Allows to cancel promises/asynchronous operations (notably: waiting for a resource load). */
+  _wasDestroyed: boolean;
+
   constructor(
     project: gdProject,
     instance: gdInitialInstance,

Extensions/Leaderboards/leaderboardstools.ts

@@ -588,7 +588,7 @@ namespace gdjs {
             break;
           case 'openPlayerAuthentication':
             gdjs.playerAuthentication
-              .openAuthenticationWindow(runtimeScene)
+              .openAuthenticationWindow(runtimeScene, event.data.options)
               .promise.then(({ status }) => {
                 if (
                   !_leaderboardViewIframe ||

Extensions/Multiplayer/JsExtension.js

@@ -882,6 +882,11 @@ module.exports = {
       )
       .addCodeOnlyParameter('currentScene', '')
       .addParameter('variable', _('Variable'), '', false)
+      .setParameterLongDescription(
+        _(
+          'Only root variables can change ownership. Arrays and structures children are synchronized with their parent.'
+        )
+      )
       .useStandardParameters(
         'number',
         gd.ParameterOptions.makeNewOptions().setDescription(_('Player number'))
@@ -916,6 +921,11 @@ module.exports = {
       )
       .addCodeOnlyParameter('currentScene', '')
       .addParameter('variable', _('Variable'), '', false)
+      .setParameterLongDescription(
+        _(
+          'Only root variables can change ownership. Arrays and structures children are synchronized with their parent.'
+        )
+      )
       .setHelpPath('/all-features/multiplayer')
       .getCodeExtraInformation()
       .setIncludeFile('Extensions/Multiplayer/peer.js')
@@ -947,6 +957,11 @@ module.exports = {
       )
       .addCodeOnlyParameter('currentScene', '')
       .addParameter('variable', _('Variable'), '', false)
+      .setParameterLongDescription(
+        _(
+          'Only root variables can change ownership. Arrays and structures children are synchronized with their parent.'
+        )
+      )
       .setHelpPath('/all-features/multiplayer')
       .getCodeExtraInformation()
       .setIncludeFile('Extensions/Multiplayer/peer.js')

Extensions/Multiplayer/messageManager.ts

@@ -917,12 +917,12 @@ namespace gdjs {
               // As we are the host, we do not cancel the message if it times out.
               shouldCancelMessageIfTimesOut: false,
             });
-            for (const peerId of otherPeerIds) {
-              debugLogger.info(
-                `Relaying ownership change of variable with Id ${variableNetworkId} to ${peerId}.`
-              );
-              sendDataTo(otherPeerIds, messageName, messageData);
-            }
+            debugLogger.info(
+              `Relaying ownership change of variable with Id ${variableNetworkId} to ${otherPeerIds.join(
+                ', '
+              )}.`
+            );
+            sendDataTo(otherPeerIds, messageName, messageData);
           }
         });
       });
@@ -1361,6 +1361,11 @@ namespace gdjs {
               // As we are the host, we do not cancel the message if it times out.
               shouldCancelMessageIfTimesOut: false,
             });
+            debugLogger.info(
+              `Relaying instance destroyed message for object ${objectName} with instance network ID ${instanceNetworkId} to ${otherPeerIds.join(
+                ', '
+              )}.`
+            );
             sendDataTo(otherPeerIds, messageName, messageData);
           }
         });

Extensions/Multiplayer/multiplayerobjectruntimebehavior.ts

@@ -120,10 +120,11 @@ namespace gdjs {
 
     private _isOwnerAsPlayerOrHost() {
       const currentPlayerNumber = gdjs.multiplayer.getCurrentPlayerNumber();
+      const isHost = gdjs.multiplayer.isCurrentPlayerHost();
 
       const isOwnerOfObject =
         currentPlayerNumber === this.playerNumber || // Player as owner.
-        (currentPlayerNumber === 1 && this.playerNumber === 0); // Host as owner.
+        (isHost && this.playerNumber === 0); // Host as owner.
 
       return isOwnerOfObject;
     }
@@ -253,6 +254,7 @@ namespace gdjs {
       // If game is running and the object belongs to a player who is not connected, destroy the object.
       // As the game may create objects before the lobby game starts, we don't want to destroy them if it's not running.
       if (
+        this.actionOnPlayerDisconnect !== 'DoNothing' && // Should not delete if flagged as such.
         this.playerNumber !== 0 && // Host is always connected.
         !gdjs.multiplayerMessageManager.isPlayerConnected(this.playerNumber)
       ) {
@@ -455,8 +457,8 @@ namespace gdjs {
 
       // Before sending the destroy message, we set up the object representing the peers
       // that we need an acknowledgment from.
-      // If we are player 1, we are connected to everyone, so we expect an acknowledgment from everyone.
-      // If we are another player, we are only connected to player 1, so we expect an acknowledgment from player 1.
+      // If we are the host, we are connected to everyone, so we expect an acknowledgment from everyone.
+      // If we are another player, we are only connected to the host, so we expect an acknowledgment from the host.
       // In both cases, this represents the list of peers the current user is connected to.
       const otherPeerIds = gdjs.multiplayerPeerJsHelper.getAllPeers();
       const {
@@ -508,7 +510,7 @@ namespace gdjs {
 
       // Update the ownership locally, so the object can be used immediately.
       // This is a prediction to allow snappy interactions.
-      // If we are player 1 or host, we will have the ownership immediately anyway.
+      // If we are host, we will have the ownership immediately anyway.
       // If we are another player, we will have the ownership as soon as the host acknowledges the change.
       // If the host does not send an acknowledgment, we will revert the ownership.
       const previousObjectPlayerNumber = this.playerNumber;
@@ -564,8 +566,8 @@ namespace gdjs {
       });
       // Before sending the changeOwner message, if we are becoming the new owner,
       // we want to ensure this message is acknowledged, by everyone we're connected to.
-      // If we are player 1, we are connected to everyone, so we expect an acknowledgment from everyone.
-      // If we are another player, we are only connected to player 1, so we expect an acknowledgment from player 1.
+      // If we are the host, we are connected to everyone, so we expect an acknowledgment from everyone.
+      // If we are another player, we are only connected to the host, so we expect an acknowledgment from the host.
       // In both cases, this represents the list of peers the current user is connected to.
       if (newObjectPlayerNumber === currentPlayerNumber) {
         const otherPeerIds = gdjs.multiplayerPeerJsHelper.getAllPeers();
@@ -581,7 +583,7 @@ namespace gdjs {
           expectedMessageName: changeOwnerAcknowledgedMessageName,
           otherPeerIds,
           // If we are not the host, we should revert the ownership if the host does not acknowledge the change.
-          shouldCancelMessageIfTimesOut: currentPlayerNumber !== 1,
+          shouldCancelMessageIfTimesOut: !gdjs.multiplayer.isCurrentPlayerHost(),
         });
       }
 

Extensions/Multiplayer/multiplayertools.ts

@@ -770,6 +770,7 @@ namespace gdjs {
 
       // When the countdown starts, if we are player number 1, we are chosen as the host.
       // We then send the peerId to others so they can connect via P2P.
+      // TODO: this should be sent by the backend, in case the lobby starts without a player 1.
       if (getCurrentPlayerNumber() === 1) {
         sendPeerId();
       }