Keep a weak reference to orphan subclasses to reuse on class reload

1 files changed, 48 insertions, 3 deletions

diff --git a/modules/gdscript/gdscript.cpp b/modules/gdscript/gdscript.cpp
index 8abf2ee7ca..8030837cd4 100644
--- a/modules/gdscript/gdscript.cpp
+++ b/modules/gdscript/gdscript.cpp
@@ -915,14 +915,43 @@ GDScript::GDScript() :
 #endif
 }
 
+void GDScript::_save_orphaned_subclasses() {
+	struct ClassRefWithName {
+		ObjectID id;
+		String fully_qualified_name;
+	};
+	Vector<ClassRefWithName> weak_subclasses;
+	// collect subclasses ObjectID and name
+	for (Map<StringName, Ref<GDScript> >::Element *E = subclasses.front(); E; E = E->next()) {
+		E->get()->_owner = NULL; //bye, you are no longer owned cause I died
+		ClassRefWithName subclass;
+		subclass.id = E->get()->get_instance_id();
+		subclass.fully_qualified_name = E->get()->fully_qualified_name;
+		weak_subclasses.push_back(subclass);
+	}
+
+	// clear subclasses to allow unused subclasses to be deleted
+	subclasses.clear();
+	// subclasses are also held by constants, clear those as well
+	constants.clear();
+
+	// keep orphan subclass only for subclasses that are still in use
+	for (int i = 0; i < weak_subclasses.size(); i++) {
+		ClassRefWithName subclass = weak_subclasses[i];
+		Object *obj = ObjectDB::get_instance(subclass.id);
+		if (!obj)
+			continue;
+		// subclass is not released
+		GDScriptLanguage::get_singleton()->add_orphan_subclass(subclass.fully_qualified_name, subclass.id);
+	}
+}
+
 GDScript::~GDScript() {
 	for (Map<StringName, GDScriptFunction *>::Element *E = member_functions.front(); E; E = E->next()) {
 		memdelete(E->get());
 	}
 
-	for (Map<StringName, Ref<GDScript> >::Element *E = subclasses.front(); E; E = E->next()) {
-		E->get()->_owner = NULL; //bye, you are no longer owned cause I died
-	}
+	_save_orphaned_subclasses();
 
 #ifdef DEBUG_ENABLED
 	if (GDScriptLanguage::get_singleton()->lock) {
@@ -2176,6 +2205,22 @@ GDScriptLanguage::~GDScriptLanguage() {
 	singleton = NULL;
 }
 
+void GDScriptLanguage::add_orphan_subclass(const String &p_qualified_name, const ObjectID &p_subclass) {
+	orphan_subclasses[p_qualified_name] = p_subclass;
+}
+
+Ref<GDScript> GDScriptLanguage::get_orphan_subclass(const String &p_qualified_name) {
+	Map<String, ObjectID>::Element *orphan_subclass_element = orphan_subclasses.find(p_qualified_name);
+	if (!orphan_subclass_element)
+		return Ref<GDScript>();
+	ObjectID orphan_subclass = orphan_subclass_element->get();
+	Object *obj = ObjectDB::get_instance(orphan_subclass);
+	orphan_subclasses.erase(orphan_subclass_element);
+	if (!obj)
+		return Ref<GDScript>();
+	return Ref<GDScript>(Object::cast_to<GDScript>(obj));
+}
+
 /*************** RESOURCE ***************/
 
 RES ResourceFormatLoaderGDScript::load(const String &p_path, const String &p_original_path, Error *r_error) {