Fix replace node deleting Node properties.

Update editor/scene_tree_dock.cpp

Co-Authored-By: Hugo Locurcio <hugo.locurcio@hugo.pro>

editor/plugins/gpu_particles_2d_editor_plugin.cpp

@@ -115,11 +115,8 @@ void GPUParticles2DEditorPlugin::_menu_callback(int p_idx) {
 
 			EditorUndoRedoManager *ur = EditorUndoRedoManager::get_singleton();
 			ur->create_action(TTR("Convert to CPUParticles2D"));
-			ur->add_do_method(SceneTreeDock::get_singleton(), "replace_node", particles, cpu_particles, true, false);
-			ur->add_do_reference(cpu_particles);
-			ur->add_undo_method(SceneTreeDock::get_singleton(), "replace_node", cpu_particles, particles, false, false);
-			ur->add_undo_reference(particles);
-			ur->commit_action();
+			SceneTreeDock::get_singleton()->replace_node(particles, cpu_particles);
+			ur->commit_action(false);
 
 		} break;
 		case MENU_RESTART: {

editor/plugins/gpu_particles_3d_editor_plugin.cpp

@@ -276,11 +276,8 @@ void GPUParticles3DEditor::_menu_option(int p_option) {
 
 			EditorUndoRedoManager *ur = EditorUndoRedoManager::get_singleton();
 			ur->create_action(TTR("Convert to CPUParticles3D"));
-			ur->add_do_method(SceneTreeDock::get_singleton(), "replace_node", node, cpu_particles, true, false);
-			ur->add_do_reference(cpu_particles);
-			ur->add_undo_method(SceneTreeDock::get_singleton(), "replace_node", cpu_particles, node, false, false);
-			ur->add_undo_reference(node);
-			ur->commit_action();
+			SceneTreeDock::get_singleton()->replace_node(node, cpu_particles);
+			ur->commit_action(false);
 
 		} break;
 		case MENU_OPTION_RESTART: {

editor/plugins/sprite_2d_editor_plugin.cpp

@@ -346,11 +346,8 @@ void Sprite2DEditor::_convert_to_mesh_2d_node() {
 
 	EditorUndoRedoManager *ur = EditorUndoRedoManager::get_singleton();
 	ur->create_action(TTR("Convert to MeshInstance2D"));
-	ur->add_do_method(SceneTreeDock::get_singleton(), "replace_node", node, mesh_instance, true, false);
-	ur->add_do_reference(mesh_instance);
-	ur->add_undo_method(SceneTreeDock::get_singleton(), "replace_node", mesh_instance, node, false, false);
-	ur->add_undo_reference(node);
-	ur->commit_action();
+	SceneTreeDock::get_singleton()->replace_node(node, mesh_instance);
+	ur->commit_action(false);
 }
 
 void Sprite2DEditor::_convert_to_polygon_2d_node() {
@@ -404,11 +401,8 @@ void Sprite2DEditor::_convert_to_polygon_2d_node() {
 
 	EditorUndoRedoManager *ur = EditorUndoRedoManager::get_singleton();
 	ur->create_action(TTR("Convert to Polygon2D"));
-	ur->add_do_method(SceneTreeDock::get_singleton(), "replace_node", node, polygon_2d_instance, true, false);
-	ur->add_do_reference(polygon_2d_instance);
-	ur->add_undo_method(SceneTreeDock::get_singleton(), "replace_node", polygon_2d_instance, node, false, false);
-	ur->add_undo_reference(node);
-	ur->commit_action();
+	SceneTreeDock::get_singleton()->replace_node(node, polygon_2d_instance);
+	ur->commit_action(false);
 }
 
 void Sprite2DEditor::_create_collision_polygon_2d_node() {

editor/scene_tree_dock.cpp

@@ -2357,16 +2357,12 @@ void SceneTreeDock::_create() {
 			Variant c = create_dialog->instantiate_selected();
 
 			ERR_FAIL_COND(!c);
-			Node *newnode = Object::cast_to<Node>(c);
-			ERR_FAIL_COND(!newnode);
-
-			ur->add_do_method(this, "replace_node", n, newnode, true, false);
-			ur->add_do_reference(newnode);
-			ur->add_undo_method(this, "replace_node", newnode, n, false, false);
-			ur->add_undo_reference(n);
+			Node *new_node = Object::cast_to<Node>(c);
+			ERR_FAIL_COND(!new_node);
+			replace_node(n, new_node);
 		}
 
-		ur->commit_action();
+		ur->commit_action(false);
 	} else if (current_option == TOOL_REPARENT_TO_NEW_NODE) {
 		List<Node *> selection = editor_selection->get_selected_node_list();
 		ERR_FAIL_COND(selection.size() <= 0);
@@ -2420,7 +2416,25 @@ void SceneTreeDock::_create() {
 	scene_tree->get_scene_tree()->grab_focus();
 }
 
-void SceneTreeDock::replace_node(Node *p_node, Node *p_by_node, bool p_keep_properties, bool p_remove_old) {
+void SceneTreeDock::replace_node(Node *p_node, Node *p_by_node) {
+	EditorUndoRedoManager *ur = EditorUndoRedoManager::get_singleton();
+	ur->create_action(TTR("Change type of node(s)"), UndoRedo::MERGE_DISABLE, p_node);
+
+	ur->add_do_method(this, "replace_node", p_node, p_by_node, true, false);
+	ur->add_do_reference(p_by_node);
+
+	_replace_node(p_node, p_by_node, true, false);
+
+	ur->add_undo_method(this, "replace_node", p_by_node, p_node, false, false);
+	ur->add_undo_reference(p_node);
+
+	perform_node_replace(nullptr, p_node, p_by_node);
+
+	ur->commit_action(false);
+}
+
+void SceneTreeDock::_replace_node(Node *p_node, Node *p_by_node, bool p_keep_properties, bool p_remove_old) {
+	ERR_FAIL_COND_MSG(!p_node->is_inside_tree(), "_replace_node() can't be called on a node outside of tree. You might have called it twice.");
 	Node *n = p_node;
 	Node *newnode = p_by_node;
 
@@ -2493,6 +2507,84 @@ void SceneTreeDock::replace_node(Node *p_node, Node *p_by_node, bool p_keep_prop
 	}
 }
 
+void SceneTreeDock::perform_node_replace(Node *p_base, Node *p_node, Node *p_by_node) {
+	if (!p_base) {
+		p_base = edited_scene;
+	}
+
+	if (!p_base) {
+		return;
+	}
+
+	// Renaming node used in node properties.
+	List<PropertyInfo> properties;
+	p_base->get_property_list(&properties);
+
+	for (const PropertyInfo &E : properties) {
+		if (!(E.usage & (PROPERTY_USAGE_STORAGE | PROPERTY_USAGE_EDITOR))) {
+			continue;
+		}
+		String propertyname = E.name;
+		Variant old_variant = p_base->get(propertyname);
+		Variant updated_variant = old_variant;
+		String warn_message;
+
+		if (_check_node_recursive(updated_variant, p_node, p_by_node, E.hint_string, warn_message)) {
+			EditorUndoRedoManager *undo_redo = EditorUndoRedoManager::get_singleton();
+			undo_redo->add_do_property(p_base, propertyname, updated_variant);
+			undo_redo->add_undo_property(p_base, propertyname, old_variant);
+			p_base->set(propertyname, updated_variant);
+			if (!warn_message.is_empty()) {
+				String node_path = (String(edited_scene->get_name()) + "/" + String(edited_scene->get_path_to(p_base))).trim_suffix("/.");
+				WARN_PRINT(warn_message + vformat(TTR("Removing the node from variable \"%s\" on node \"%s\"."), propertyname, node_path));
+			}
+		}
+	}
+
+	for (int i = 0; i < p_base->get_child_count(); i++) {
+		perform_node_replace(p_base->get_child(i), p_node, p_by_node);
+	}
+}
+
+bool SceneTreeDock::_check_node_recursive(Variant &r_variant, Node *p_node, Node *p_by_node, const String type_hint, String &r_warn_message) {
+	switch (r_variant.get_type()) {
+		case Variant::OBJECT: {
+			if (p_node == r_variant) {
+				if (p_by_node->is_class(type_hint) || EditorNode::get_singleton()->is_object_of_custom_type(p_by_node, type_hint)) {
+					r_variant = p_by_node;
+				} else {
+					r_variant = memnew(Object);
+					r_warn_message = vformat(TTR("The node's new type is incompatible with an exported variable (expected %s, but type is %s)."), type_hint, p_by_node->get_class());
+				}
+				return true;
+			}
+		} break;
+
+		case Variant::ARRAY: {
+			Array a = r_variant;
+			bool updated = false;
+			for (int i = 0; i < a.size(); i++) {
+				Variant value = a[i];
+				if (_check_node_recursive(value, p_node, p_by_node, type_hint.get_slice(":", 1), r_warn_message)) {
+					if (!updated) {
+						a = a.duplicate(); // Need to duplicate for undo-redo to work.
+						updated = true;
+					}
+					a[i] = value;
+				}
+			}
+			if (updated) {
+				r_variant = a;
+				return true;
+			}
+		} break;
+		default: {
+		}
+	}
+
+	return false;
+}
+
 void SceneTreeDock::set_edited_scene(Node *p_scene) {
 	edited_scene = p_scene;
 }
@@ -3636,7 +3728,7 @@ void SceneTreeDock::_bind_methods() {
 
 	ClassDB::bind_method(D_METHOD("instantiate"), &SceneTreeDock::instantiate);
 	ClassDB::bind_method(D_METHOD("get_tree_editor"), &SceneTreeDock::get_tree_editor);
-	ClassDB::bind_method(D_METHOD("replace_node"), &SceneTreeDock::replace_node);
+	ClassDB::bind_method(D_METHOD("replace_node"), &SceneTreeDock::_replace_node);
 
 	ADD_SIGNAL(MethodInfo("remote_tree_selected"));
 	ADD_SIGNAL(MethodInfo("add_node_used"));

editor/scene_tree_dock.h

@@ -282,6 +282,8 @@ class SceneTreeDock : public VBoxContainer {
 
 	bool _update_node_path(Node *p_root_node, NodePath &r_node_path, HashMap<Node *, NodePath> *p_renames) const;
 	bool _check_node_path_recursive(Node *p_root_node, Variant &r_variant, HashMap<Node *, NodePath> *p_renames) const;
+	bool _check_node_recursive(Variant &r_variant, Node *p_node, Node *p_by_node, const String type_hint, String &r_warn_message);
+	void _replace_node(Node *p_node, Node *p_by_node, bool p_keep_properties = true, bool p_remove_old = true);
 
 private:
 	static SceneTreeDock *singleton;
@@ -307,6 +309,7 @@ class SceneTreeDock : public VBoxContainer {
 	void set_selected(Node *p_node, bool p_emit_selected = false);
 	void fill_path_renames(Node *p_node, Node *p_new_parent, HashMap<Node *, NodePath> *p_renames);
 	void perform_node_renames(Node *p_base, HashMap<Node *, NodePath> *p_renames, HashMap<Ref<Animation>, HashSet<int>> *r_rem_anims = nullptr);
+	void perform_node_replace(Node *p_base, Node *p_node, Node *p_by_node);
 	SceneTreeEditor *get_tree_editor() { return scene_tree; }
 	EditorData *get_editor_data() { return editor_data; }
 
@@ -316,7 +319,7 @@ class SceneTreeDock : public VBoxContainer {
 	void show_tab_buttons();
 	void hide_tab_buttons();
 
-	void replace_node(Node *p_node, Node *p_by_node, bool p_keep_properties = true, bool p_remove_old = true);
+	void replace_node(Node *p_node, Node *p_by_node);
 
 	void attach_script_to_selected(bool p_extend);
 	void open_script_dialog(Node *p_for_node, bool p_extend);