Add GDExtension support to Script

* Ability to create script languages from GDExtension
* Some additions to gdnative_extension.h to make this happen
* Moved the GDExtension binder to core

This now allows creating scripting languages from GDExtension, with the same ease as if it was a module. It replaces the old PluginScript from Godot 3.x.
Warning: GodotCPP will need to be updated to support this (it may be a bit of work as ScriptInstance needs to be created over there again).

11 files changed, 1291 insertions, 48 deletions

diff --git a/core/core_bind.cpp b/core/core_bind.cpp
index 7150459d84..8b060b09f9 100644
--- a/core/core_bind.cpp
+++ b/core/core_bind.cpp
@@ -2296,6 +2296,18 @@ Vector<String> Engine::get_singleton_list() const {
 	return ret;
 }
 
+void Engine::register_script_language(ScriptLanguage *p_language) {
+	ScriptServer::register_language(p_language);
+}
+
+int Engine::get_script_language_count() {
+	return ScriptServer::get_language_count();
+}
+
+ScriptLanguage *Engine::get_script_language(int p_index) const {
+	return ScriptServer::get_language(p_index);
+}
+
 void Engine::set_editor_hint(bool p_enabled) {
 	::Engine::get_singleton()->set_editor_hint(p_enabled);
 }
@@ -2347,6 +2359,10 @@ void Engine::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("unregister_singleton", "name"), &Engine::unregister_singleton);
 	ClassDB::bind_method(D_METHOD("get_singleton_list"), &Engine::get_singleton_list);
 
+	ClassDB::bind_method(D_METHOD("register_script_language", "language"), &Engine::register_script_language);
+	ClassDB::bind_method(D_METHOD("get_script_language_count"), &Engine::get_script_language_count);
+	ClassDB::bind_method(D_METHOD("get_script_language", "index"), &Engine::get_script_language);
+
 	ClassDB::bind_method(D_METHOD("is_editor_hint"), &Engine::is_editor_hint);
 
 	ClassDB::bind_method(D_METHOD("set_print_error_messages", "enabled"), &Engine::set_print_error_messages);
diff --git a/core/core_bind.h b/core/core_bind.h
index a0fdf26dff..2942f54a15 100644
--- a/core/core_bind.h
+++ b/core/core_bind.h
@@ -38,6 +38,7 @@
 #include "core/io/image.h"
 #include "core/io/resource_loader.h"
 #include "core/io/resource_saver.h"
+#include "core/object/script_language.h"
 #include "core/os/os.h"
 #include "core/os/semaphore.h"
 #include "core/os/thread.h"
@@ -664,6 +665,10 @@ public:
 	void unregister_singleton(const StringName &p_name);
 	Vector<String> get_singleton_list() const;
 
+	void register_script_language(ScriptLanguage *p_language);
+	int get_script_language_count();
+	ScriptLanguage *get_script_language(int p_index) const;
+
 	void set_editor_hint(bool p_enabled);
 	bool is_editor_hint() const;
 
diff --git a/core/extension/SCsub b/core/extension/SCsub
index a3a54250c1..23727c1b76 100644
--- a/core/extension/SCsub
+++ b/core/extension/SCsub
@@ -2,6 +2,12 @@
 
 Import("env")
 
+import make_wrappers
+from platform_methods import run_in_subprocess
+
+env.CommandNoCache(["ext_wrappers.gen.inc"], "make_wrappers.py", run_in_subprocess(make_wrappers.run))
+
+
 env_extension = env.Clone()
 
 env_extension.add_source_files(env.core_sources, "*.cpp")
diff --git a/core/extension/gdnative_interface.cpp b/core/extension/gdnative_interface.cpp
index d0461611ec..b5b340731d 100644
--- a/core/extension/gdnative_interface.cpp
+++ b/core/extension/gdnative_interface.cpp
@@ -32,6 +32,7 @@
 
 #include "core/config/engine.h"
 #include "core/object/class_db.h"
+#include "core/object/script_language_extension.h"
 #include "core/os/memory.h"
 #include "core/variant/variant.h"
 #include "core/version.h"
@@ -864,6 +865,13 @@ static GDObjectInstanceID gdnative_object_get_instance_id(const GDNativeObjectPt
 	return (GDObjectInstanceID)o->get_instance_id();
 }
 
+static GDNativeScriptInstancePtr gdnative_script_instance_create(const GDNativeExtensionScriptInstanceInfo *p_info, GDNativeExtensionScriptInstanceDataPtr p_instance_data) {
+	ScriptInstanceExtension *script_instance_extension = memnew(ScriptInstanceExtension);
+	script_instance_extension->instance = p_instance_data;
+	script_instance_extension->native_info = p_info;
+	return reinterpret_cast<GDNativeScriptInstancePtr>(script_instance_extension);
+}
+
 static GDNativeMethodBindPtr gdnative_classdb_get_method_bind(const char *p_classname, const char *p_methodname, GDNativeInt p_hash) {
 	MethodBind *mb = ClassDB::get_method(StringName(p_classname), StringName(p_methodname));
 	ERR_FAIL_COND_V(!mb, nullptr);
@@ -1032,6 +1040,10 @@ void gdnative_setup_interface(GDNativeInterface *p_interface) {
 	gdni.object_get_instance_from_id = gdnative_object_get_instance_from_id;
 	gdni.object_get_instance_id = gdnative_object_get_instance_id;
 
+	/* SCRIPT INSTANCE */
+
+	gdni.script_instance_create = gdnative_script_instance_create;
+
 	/* CLASSDB */
 
 	gdni.classdb_construct_object = gdnative_classdb_construct_object;
diff --git a/core/extension/gdnative_interface.h b/core/extension/gdnative_interface.h
index cc2957ec56..50c747a7b4 100644
--- a/core/extension/gdnative_interface.h
+++ b/core/extension/gdnative_interface.h
@@ -205,6 +205,17 @@ typedef struct {
 	uint32_t usage;
 } GDNativePropertyInfo;
 
+typedef struct {
+	const char *name;
+	GDNativePropertyInfo return_value;
+	uint32_t flags; // From GDNativeExtensionClassMethodFlags
+	int32_t id;
+	GDNativePropertyInfo *arguments;
+	uint32_t argument_count;
+	GDNativeVariantPtr default_arguments;
+	uint32_t default_argument_count;
+} GDNativeMethodInfo;
+
 typedef const GDNativePropertyInfo *(*GDNativeExtensionClassGetPropertyList)(GDExtensionClassInstancePtr p_instance, uint32_t *r_count);
 typedef void (*GDNativeExtensionClassFreePropertyList)(GDExtensionClassInstancePtr p_instance, const GDNativePropertyInfo *p_list);
 typedef void (*GDNativeExtensionClassNotification)(GDExtensionClassInstancePtr p_instance, int32_t p_what);
@@ -289,6 +300,79 @@ typedef struct {
 	GDNativeVariantPtr *default_arguments;
 } GDNativeExtensionClassMethodInfo;
 
+/* SCRIPT INSTANCE EXTENSION */
+
+typedef void *GDNativeExtensionScriptInstanceDataPtr; // Pointer to custom ScriptInstance native implementation
+
+typedef GDNativeBool (*GDNativeExtensionScriptInstanceSet)(GDNativeExtensionScriptInstanceDataPtr p_instance, const GDNativeStringNamePtr p_name, const GDNativeVariantPtr p_value);
+typedef GDNativeBool (*GDNativeExtensionScriptInstanceGet)(GDNativeExtensionScriptInstanceDataPtr p_instance, const GDNativeStringNamePtr p_name, GDNativeVariantPtr r_ret);
+typedef const GDNativePropertyInfo *(*GDNativeExtensionScriptInstanceGetPropertyList)(GDNativeExtensionScriptInstanceDataPtr p_instance, uint32_t *r_count);
+typedef void (*GDNativeExtensionScriptInstanceFreePropertyList)(GDNativeExtensionScriptInstanceDataPtr p_instance, const GDNativePropertyInfo *p_list);
+typedef GDNativeVariantType (*GDNativeExtensionScriptInstanceGetPropertyType)(GDNativeExtensionScriptInstanceDataPtr p_instance, const GDNativeStringNamePtr p_name, GDNativeBool *r_is_valid);
+
+typedef GDNativeObjectPtr (*GDNativeExtensionScriptInstanceGetOwner)(GDNativeExtensionScriptInstanceDataPtr p_instance);
+typedef void (*GDNativeExtensionScriptInstancePropertyStateAdd)(const GDNativeStringNamePtr p_name, const GDNativeVariantPtr p_value, void *p_userdata);
+typedef void (*GDNativeExtensionScriptInstanceGetPropertyState)(GDNativeExtensionScriptInstanceDataPtr p_instance, GDNativeExtensionScriptInstancePropertyStateAdd p_add_func, void *p_userdata);
+
+typedef const GDNativeMethodInfo *(*GDNativeExtensionScriptInstanceGetMethodList)(GDNativeExtensionScriptInstanceDataPtr p_instance, uint32_t *r_count);
+typedef void (*GDNativeExtensionScriptInstanceFreeMethodList)(GDNativeExtensionScriptInstanceDataPtr p_instance, const GDNativeMethodInfo *p_list);
+
+typedef GDNativeBool (*GDNativeExtensionScriptInstanceHasMethod)(GDNativeExtensionScriptInstanceDataPtr p_instance, const GDNativeStringNamePtr p_name);
+
+typedef void (*GDNativeExtensionScriptInstanceCall)(GDNativeExtensionScriptInstanceDataPtr p_self, const GDNativeStringNamePtr p_method, const GDNativeVariantPtr *p_args, const GDNativeInt p_argument_count, GDNativeVariantPtr r_return, GDNativeCallError *r_error);
+typedef void (*GDNativeExtensionScriptInstanceNotification)(GDNativeExtensionScriptInstanceDataPtr p_instance, int32_t p_what);
+typedef const char *(*GDNativeExtensionScriptInstanceToString)(GDNativeExtensionScriptInstanceDataPtr p_instance, GDNativeBool *r_is_valid);
+
+typedef void (*GDNativeExtensionScriptInstanceRefCountIncremented)(GDNativeExtensionScriptInstanceDataPtr p_instance);
+typedef GDNativeBool (*GDNativeExtensionScriptInstanceRefCountDecremented)(GDNativeExtensionScriptInstanceDataPtr p_instance);
+
+typedef GDNativeObjectPtr (*GDNativeExtensionScriptInstanceGetScript)(GDNativeExtensionScriptInstanceDataPtr p_instance);
+typedef GDNativeBool (*GDNativeExtensionScriptInstanceIsPlaceholder)(GDNativeExtensionScriptInstanceDataPtr p_instance);
+
+typedef void *GDNativeExtensionScriptLanguagePtr;
+
+typedef GDNativeExtensionScriptLanguagePtr (*GDNativeExtensionScriptInstanceGetLanguage)(GDNativeExtensionScriptInstanceDataPtr p_instance);
+
+typedef void (*GDNativeExtensionScriptInstanceFree)(GDNativeExtensionScriptInstanceDataPtr p_instance);
+
+typedef void *GDNativeScriptInstancePtr; // Pointer to ScriptInstance.
+
+typedef struct {
+	GDNativeExtensionScriptInstanceSet set_func;
+	GDNativeExtensionScriptInstanceGet get_func;
+	GDNativeExtensionScriptInstanceGetPropertyList get_property_list_func;
+	GDNativeExtensionScriptInstanceFreePropertyList free_property_list_func;
+	GDNativeExtensionScriptInstanceGetPropertyType get_property_type_func;
+
+	GDNativeExtensionScriptInstanceGetOwner get_owner_func;
+	GDNativeExtensionScriptInstanceGetPropertyState get_property_state_func;
+
+	GDNativeExtensionScriptInstanceGetMethodList get_method_list_func;
+	GDNativeExtensionScriptInstanceFreeMethodList free_method_list_func;
+
+	GDNativeExtensionScriptInstanceHasMethod has_method_func;
+
+	GDNativeExtensionScriptInstanceCall call_func;
+	GDNativeExtensionScriptInstanceNotification notification_func;
+
+	GDNativeExtensionScriptInstanceToString to_string_func;
+
+	GDNativeExtensionScriptInstanceRefCountIncremented refcount_incremented_func;
+	GDNativeExtensionScriptInstanceRefCountDecremented refcount_decremented_func;
+
+	GDNativeExtensionScriptInstanceGetScript get_script_func;
+
+	GDNativeExtensionScriptInstanceIsPlaceholder is_placeholder_func;
+
+	GDNativeExtensionScriptInstanceSet set_fallback_func;
+	GDNativeExtensionScriptInstanceGet get_fallback_func;
+
+	GDNativeExtensionScriptInstanceGetLanguage get_language_func;
+
+	GDNativeExtensionScriptInstanceFree free_func;
+
+} GDNativeExtensionScriptInstanceInfo;
+
 /* INTERFACE */
 
 typedef struct {
@@ -441,6 +525,10 @@ typedef struct {
 	GDNativeObjectPtr (*object_get_instance_from_id)(GDObjectInstanceID p_instance_id);
 	GDObjectInstanceID (*object_get_instance_id)(const GDNativeObjectPtr p_object);
 
+	/* SCRIPT INSTANCE */
+
+	GDNativeScriptInstancePtr (*script_instance_create)(const GDNativeExtensionScriptInstanceInfo *p_info, GDNativeExtensionScriptInstanceDataPtr p_instance_data);
+
 	/* CLASSDB */
 	GDNativeObjectPtr (*classdb_construct_object)(const char *p_classname); /* The passed class must be a built-in godot class, or an already-registered extension class. In both case, object_set_instance should be called to fully initialize the object. */
 	GDNativeMethodBindPtr (*classdb_get_method_bind)(const char *p_classname, const char *p_methodname, GDNativeInt p_hash);
diff --git a/core/extension/make_wrappers.py b/core/extension/make_wrappers.py
new file mode 100644
index 0000000000..862d313fba
--- /dev/null
+++ b/core/extension/make_wrappers.py
@@ -0,0 +1,93 @@
+proto = """
+#define EXBIND$VER($RETTYPE m_name$ARG) \\
+GDVIRTUAL$VER($RETTYPE_##m_name$ARG)\\
+virtual $RETVAL m_name($FUNCARGS) $CONST override { \\
+    $RETPRE\\
+    GDVIRTUAL_REQUIRED_CALL(_##m_name$CALLARGS$RETREF);\\
+    $RETPOST\\
+}
+"""
+
+
+def generate_version(argcount, const=False, returns=False):
+    s = proto
+    sproto = str(argcount)
+    method_info = ""
+    if returns:
+        sproto += "R"
+        s = s.replace("$RETTYPE", "m_ret, ")
+        s = s.replace("$RETVAL", "m_ret")
+        s = s.replace("$RETPRE", "m_ret ret; ZeroInitializer<m_ret>::initialize(ret);\\\n")
+        s = s.replace("$RETPOST", "return ret;\\\n")
+
+    else:
+        s = s.replace("$RETTYPE", "")
+        s = s.replace("$RETVAL", "void")
+        s = s.replace("$RETPRE", "")
+        s = s.replace("$RETPOST", "return;")
+
+    if const:
+        sproto += "C"
+        s = s.replace("$CONST", "const")
+    else:
+        s = s.replace("$CONST", "")
+
+    s = s.replace("$VER", sproto)
+    argtext = ""
+    funcargs = ""
+    callargs = ""
+
+    for i in range(argcount):
+        if i > 0:
+            funcargs += ", "
+
+        argtext += ", m_type" + str(i + 1)
+        funcargs += "m_type" + str(i + 1) + " arg" + str(i + 1)
+        callargs += ", arg" + str(i + 1)
+
+    if argcount:
+        s = s.replace("$ARG", argtext)
+        s = s.replace("$FUNCARGS", funcargs)
+        s = s.replace("$CALLARGS", callargs)
+    else:
+        s = s.replace("$ARG", "")
+        s = s.replace("$FUNCARGS", funcargs)
+        s = s.replace("$CALLARGS", callargs)
+
+    if returns:
+        s = s.replace("$RETREF", ", ret")
+    else:
+        s = s.replace("$RETREF", "")
+
+    return s
+
+
+def run(target, source, env):
+
+    max_versions = 12
+
+    txt = """
+#ifndef GDEXTENSION_WRAPPERS_GEN_H
+#define GDEXTENSION_WRAPPERS_GEN_H
+
+
+"""
+
+    for i in range(max_versions + 1):
+
+        txt += "/* " + str(i) + " Arguments */\n\n"
+        txt += generate_version(i, False, False)
+        txt += generate_version(i, False, True)
+        txt += generate_version(i, True, False)
+        txt += generate_version(i, True, True)
+
+    txt += "#endif"
+
+    with open(target[0], "w") as f:
+        f.write(txt)
+
+
+if __name__ == "__main__":
+    from platform_methods import subprocess_main
+
+    subprocess_main(globals())
diff --git a/core/object/class_db.cpp b/core/object/class_db.cpp
index e09c6cb97c..51ca06d9d2 100644
--- a/core/object/class_db.cpp
+++ b/core/object/class_db.cpp
@@ -1485,9 +1485,10 @@ void ClassDB::add_virtual_method(const StringName &p_class, const MethodInfo &p_
 	if (p_object_core) {
 		mi.flags |= METHOD_FLAG_OBJECT_CORE;
 	}
-	if (p_arg_names.size()) {
+
+	if (!p_object_core) {
 		if (p_arg_names.size() != mi.arguments.size()) {
-			WARN_PRINT("Mismatch argument name count for virtual function: " + String(p_class) + "::" + p_method.name);
+			WARN_PRINT("Mismatch argument name count for virtual method: " + String(p_class) + "::" + p_method.name);
 		} else {
 			for (int i = 0; i < p_arg_names.size(); i++) {
 				mi.arguments[i].name = p_arg_names[i];
@@ -1495,6 +1496,10 @@ void ClassDB::add_virtual_method(const StringName &p_class, const MethodInfo &p_
 		}
 	}
 
+	if (classes[p_class].virtual_methods_map.has(p_method.name)) {
+		// overloading not supported
+		ERR_FAIL_MSG("Virtual method already bound '" + String(p_class) + "::" + p_method.name + "'.");
+	}
 	classes[p_class].virtual_methods.push_back(mi);
 	classes[p_class].virtual_methods_map[p_method.name] = mi;
 
diff --git a/core/object/script_language.h b/core/object/script_language.h
index 2122f785b6..6161a0fc0f 100644
--- a/core/object/script_language.h
+++ b/core/object/script_language.h
@@ -132,7 +132,7 @@ public:
 	virtual Error reload(bool p_keep_state = false) = 0;
 
 #ifdef TOOLS_ENABLED
-	virtual const Vector<DocData::ClassDoc> &get_documentation() const = 0;
+	virtual Vector<DocData::ClassDoc> get_documentation() const = 0;
 #endif // TOOLS_ENABLED
 
 	virtual bool has_method(const StringName &p_method) const = 0;
@@ -212,44 +212,12 @@ public:
 	virtual void property_set_fallback(const StringName &p_name, const Variant &p_value, bool *r_valid);
 	virtual Variant property_get_fallback(const StringName &p_name, bool *r_valid);
 
-	virtual const Vector<Multiplayer::RPCConfig> get_rpc_methods() const = 0;
+	virtual const Vector<Multiplayer::RPCConfig> get_rpc_methods() const { return get_script()->get_rpc_methods(); }
 
 	virtual ScriptLanguage *get_language() = 0;
 	virtual ~ScriptInstance();
 };
 
-struct ScriptCodeCompletionOption {
-	/* Keep enum in Sync with:                               */
-	/* /scene/gui/code_edit.h - CodeEdit::CodeCompletionKind */
-	enum Kind {
-		KIND_CLASS,
-		KIND_FUNCTION,
-		KIND_SIGNAL,
-		KIND_VARIABLE,
-		KIND_MEMBER,
-		KIND_ENUM,
-		KIND_CONSTANT,
-		KIND_NODE_PATH,
-		KIND_FILE_PATH,
-		KIND_PLAIN_TEXT,
-	};
-	Kind kind = KIND_PLAIN_TEXT;
-	String display;
-	String insert_text;
-	Color font_color;
-	RES icon;
-	Variant default_value;
-	Vector<Pair<int, int>> matches;
-
-	ScriptCodeCompletionOption() {}
-
-	ScriptCodeCompletionOption(const String &p_text, Kind p_kind) {
-		display = p_text;
-		insert_text = p_text;
-		kind = p_kind;
-	}
-};
-
 class ScriptCodeCompletionCache {
 	static ScriptCodeCompletionCache *singleton;
 
@@ -261,7 +229,8 @@ public:
 	virtual ~ScriptCodeCompletionCache() {}
 };
 
-class ScriptLanguage {
+class ScriptLanguage : public Object {
+	GDCLASS(ScriptLanguage, Object)
 public:
 	virtual String get_name() const = 0;
 
@@ -326,19 +295,55 @@ public:
 	virtual Error open_in_external_editor(const Ref<Script> &p_script, int p_line, int p_col) { return ERR_UNAVAILABLE; }
 	virtual bool overrides_external_editor() { return false; }
 
-	virtual Error complete_code(const String &p_code, const String &p_path, Object *p_owner, List<ScriptCodeCompletionOption> *r_options, bool &r_force, String &r_call_hint) { return ERR_UNAVAILABLE; }
+	/* Keep enum in Sync with:                               */
+	/* /scene/gui/code_edit.h - CodeEdit::CodeCompletionKind */
+	enum CodeCompletionKind {
+		CODE_COMPLETION_KIND_CLASS,
+		CODE_COMPLETION_KIND_FUNCTION,
+		CODE_COMPLETION_KIND_SIGNAL,
+		CODE_COMPLETION_KIND_VARIABLE,
+		CODE_COMPLETION_KIND_MEMBER,
+		CODE_COMPLETION_KIND_ENUM,
+		CODE_COMPLETION_KIND_CONSTANT,
+		CODE_COMPLETION_KIND_NODE_PATH,
+		CODE_COMPLETION_KIND_FILE_PATH,
+		CODE_COMPLETION_KIND_PLAIN_TEXT,
+		CODE_COMPLETION_KIND_MAX
+	};
+
+	struct CodeCompletionOption {
+		CodeCompletionKind kind = CODE_COMPLETION_KIND_PLAIN_TEXT;
+		String display;
+		String insert_text;
+		Color font_color;
+		RES icon;
+		Variant default_value;
+		Vector<Pair<int, int>> matches;
+
+		CodeCompletionOption() {}
+
+		CodeCompletionOption(const String &p_text, CodeCompletionKind p_kind) {
+			display = p_text;
+			insert_text = p_text;
+			kind = p_kind;
+		}
+	};
+
+	virtual Error complete_code(const String &p_code, const String &p_path, Object *p_owner, List<CodeCompletionOption> *r_options, bool &r_force, String &r_call_hint) { return ERR_UNAVAILABLE; }
+
+	enum LookupResultType {
+		LOOKUP_RESULT_SCRIPT_LOCATION,
+		LOOKUP_RESULT_CLASS,
+		LOOKUP_RESULT_CLASS_CONSTANT,
+		LOOKUP_RESULT_CLASS_PROPERTY,
+		LOOKUP_RESULT_CLASS_METHOD,
+		LOOKUP_RESULT_CLASS_ENUM,
+		LOOKUP_RESULT_CLASS_TBD_GLOBALSCOPE,
+		LOOKUP_RESULT_MAX
+	};
 
 	struct LookupResult {
-		enum Type {
-			RESULT_SCRIPT_LOCATION,
-			RESULT_CLASS,
-			RESULT_CLASS_CONSTANT,
-			RESULT_CLASS_PROPERTY,
-			RESULT_CLASS_METHOD,
-			RESULT_CLASS_ENUM,
-			RESULT_CLASS_TBD_GLOBALSCOPE
-		};
-		Type type;
+		LookupResultType type;
 		Ref<Script> script;
 		String class_name;
 		String class_member;
diff --git a/core/object/script_language_extension.cpp b/core/object/script_language_extension.cpp
new file mode 100644
index 0000000000..bf0966c803
--- /dev/null
+++ b/core/object/script_language_extension.cpp
@@ -0,0 +1,175 @@
+/*************************************************************************/
+/*  script_language_extension.cpp                                        */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "script_language_extension.h"
+
+void ScriptExtension::_bind_methods() {
+	GDVIRTUAL_BIND(_editor_can_reload_from_file);
+	GDVIRTUAL_BIND(_placeholder_erased, "placeholder");
+
+	GDVIRTUAL_BIND(_can_instantiate);
+	GDVIRTUAL_BIND(_get_base_script);
+	GDVIRTUAL_BIND(_inherits_script, "script");
+
+	GDVIRTUAL_BIND(_get_instance_base_type);
+	GDVIRTUAL_BIND(_instance_create, "for_object");
+	GDVIRTUAL_BIND(_placeholder_instance_create, "for_object");
+
+	GDVIRTUAL_BIND(_instance_has, "object");
+
+	GDVIRTUAL_BIND(_has_source_code);
+	GDVIRTUAL_BIND(_get_source_code);
+
+	GDVIRTUAL_BIND(_set_source_code, "code");
+	GDVIRTUAL_BIND(_reload, "keep_state");
+
+	GDVIRTUAL_BIND(_get_documentation);
+
+	GDVIRTUAL_BIND(_has_method, "method");
+	GDVIRTUAL_BIND(_get_method_info, "method");
+
+	GDVIRTUAL_BIND(_is_tool);
+	GDVIRTUAL_BIND(_is_valid);
+	GDVIRTUAL_BIND(_get_language);
+
+	GDVIRTUAL_BIND(_has_script_signal, "signal");
+	GDVIRTUAL_BIND(_get_script_signal_list);
+
+	GDVIRTUAL_BIND(_get_property_default_value, "property");
+
+	GDVIRTUAL_BIND(_update_exports);
+	GDVIRTUAL_BIND(_get_script_method_list);
+	GDVIRTUAL_BIND(_get_script_property_list);
+
+	GDVIRTUAL_BIND(_get_member_line, "member");
+
+	GDVIRTUAL_BIND(_get_constants);
+	GDVIRTUAL_BIND(_get_members);
+	GDVIRTUAL_BIND(_is_placeholder_fallback_enabled);
+
+	GDVIRTUAL_BIND(_get_rpc_methods);
+}
+
+void ScriptLanguageExtension::_bind_methods() {
+	GDVIRTUAL_BIND(_get_name);
+	GDVIRTUAL_BIND(_init);
+	GDVIRTUAL_BIND(_get_type);
+	GDVIRTUAL_BIND(_get_extension);
+	GDVIRTUAL_BIND(_execute_file, "path");
+	GDVIRTUAL_BIND(_finish);
+
+	GDVIRTUAL_BIND(_get_reserved_words);
+	GDVIRTUAL_BIND(_is_control_flow_keyword, "keyword");
+	GDVIRTUAL_BIND(_get_comment_delimiters);
+	GDVIRTUAL_BIND(_get_string_delimiters);
+	GDVIRTUAL_BIND(_make_template, "template", "class_name", "base_class_name");
+	GDVIRTUAL_BIND(_get_built_in_templates, "object");
+	GDVIRTUAL_BIND(_is_using_templates);
+	GDVIRTUAL_BIND(_validate, "script", "path", "validate_functions", "validate_errors", "validate_warnings", "validate_safe_lines");
+
+	GDVIRTUAL_BIND(_validate_path, "path");
+	GDVIRTUAL_BIND(_create_script);
+	GDVIRTUAL_BIND(_has_named_classes);
+	GDVIRTUAL_BIND(_supports_builtin_mode);
+	GDVIRTUAL_BIND(_supports_documentation);
+	GDVIRTUAL_BIND(_can_inherit_from_file);
+	GDVIRTUAL_BIND(_find_function, "class_name", "function_name");
+	GDVIRTUAL_BIND(_make_function, "class_name", "function_name", "function_args");
+	GDVIRTUAL_BIND(_open_in_external_editor, "script", "line", "column");
+	GDVIRTUAL_BIND(_overrides_external_editor);
+
+	GDVIRTUAL_BIND(_complete_code, "code", "path", "owner");
+	GDVIRTUAL_BIND(_lookup_code, "code", "symbol", "path", "owner");
+	GDVIRTUAL_BIND(_auto_indent_code, "code", "from_line", "to_line");
+
+	GDVIRTUAL_BIND(_add_global_constant, "name", "value");
+	GDVIRTUAL_BIND(_add_named_global_constant, "name", "value");
+	GDVIRTUAL_BIND(_remove_named_global_constant, "name");
+
+	GDVIRTUAL_BIND(_thread_enter);
+	GDVIRTUAL_BIND(_thread_exit);
+	GDVIRTUAL_BIND(_debug_get_error);
+	GDVIRTUAL_BIND(_debug_get_stack_level_count);
+
+	GDVIRTUAL_BIND(_debug_get_stack_level_line, "level");
+	GDVIRTUAL_BIND(_debug_get_stack_level_function, "level");
+	GDVIRTUAL_BIND(_debug_get_stack_level_locals, "level", "max_subitems", "max_depth");
+	GDVIRTUAL_BIND(_debug_get_stack_level_members, "level", "max_subitems", "max_depth");
+	GDVIRTUAL_BIND(_debug_get_stack_level_instance, "level");
+	GDVIRTUAL_BIND(_debug_get_globals, "max_subitems", "max_depth");
+	GDVIRTUAL_BIND(_debug_parse_stack_level_expression, "level", "expression", "max_subitems", "max_depth");
+
+	GDVIRTUAL_BIND(_debug_get_current_stack_info);
+
+	GDVIRTUAL_BIND(_reload_all_scripts);
+	GDVIRTUAL_BIND(_reload_tool_script, "script", "soft_reload");
+
+	GDVIRTUAL_BIND(_get_recognized_extensions);
+	GDVIRTUAL_BIND(_get_public_functions);
+	GDVIRTUAL_BIND(_get_public_constants);
+
+	GDVIRTUAL_BIND(_profiling_start);
+	GDVIRTUAL_BIND(_profiling_stop);
+
+	GDVIRTUAL_BIND(_profiling_get_accumulated_data, "info_array", "info_max");
+	GDVIRTUAL_BIND(_profiling_get_frame_data, "info_array", "info_max");
+
+	GDVIRTUAL_BIND(_alloc_instance_binding_data, "object");
+	GDVIRTUAL_BIND(_free_instance_binding_data, "data");
+
+	GDVIRTUAL_BIND(_refcount_incremented_instance_binding, "object");
+	GDVIRTUAL_BIND(_refcount_decremented_instance_binding, "object");
+
+	GDVIRTUAL_BIND(_frame);
+
+	GDVIRTUAL_BIND(_handles_global_class_type, "type");
+	GDVIRTUAL_BIND(_get_global_class_name, "path");
+
+	BIND_ENUM_CONSTANT(LOOKUP_RESULT_SCRIPT_LOCATION);
+	BIND_ENUM_CONSTANT(LOOKUP_RESULT_CLASS);
+	BIND_ENUM_CONSTANT(LOOKUP_RESULT_CLASS_CONSTANT);
+	BIND_ENUM_CONSTANT(LOOKUP_RESULT_CLASS_PROPERTY);
+	BIND_ENUM_CONSTANT(LOOKUP_RESULT_CLASS_METHOD);
+	BIND_ENUM_CONSTANT(LOOKUP_RESULT_CLASS_ENUM);
+	BIND_ENUM_CONSTANT(LOOKUP_RESULT_CLASS_TBD_GLOBALSCOPE);
+	BIND_ENUM_CONSTANT(LOOKUP_RESULT_MAX);
+
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_CLASS);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_FUNCTION);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_SIGNAL);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_VARIABLE);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_MEMBER);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_ENUM);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_CONSTANT);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_NODE_PATH);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_FILE_PATH);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_PLAIN_TEXT);
+	BIND_ENUM_CONSTANT(CODE_COMPLETION_KIND_MAX);
+}
diff --git a/core/object/script_language_extension.h b/core/object/script_language_extension.h
new file mode 100644
index 0000000000..b9ec79da26
--- /dev/null
+++ b/core/object/script_language_extension.h
@@ -0,0 +1,832 @@
+/*************************************************************************/
+/*  script_language_extension.h                                          */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef SCRIPT_LANGUAGE_EXTENSION_H
+#define SCRIPT_LANGUAGE_EXTENSION_H
+
+#include "core/extension/ext_wrappers.gen.inc"
+#include "core/object/gdvirtual.gen.inc"
+#include "core/object/script_language.h"
+#include "core/variant/native_ptr.h"
+#include "core/variant/typed_array.h"
+
+class ScriptExtension : public Script {
+	GDCLASS(ScriptExtension, Script)
+
+protected:
+	EXBIND0R(bool, editor_can_reload_from_file)
+
+	GDVIRTUAL1(_placeholder_erased, GDNativePtr<void>)
+	virtual void _placeholder_erased(PlaceHolderScriptInstance *p_placeholder) override {
+		GDVIRTUAL_CALL(_placeholder_erased, p_placeholder);
+	}
+
+	static void _bind_methods();
+
+public:
+	EXBIND0RC(bool, can_instantiate)
+	EXBIND0RC(Ref<Script>, get_base_script)
+	EXBIND1RC(bool, inherits_script, const Ref<Script> &)
+	EXBIND0RC(StringName, get_instance_base_type)
+
+	GDVIRTUAL1RC(GDNativePtr<void>, _instance_create, Object *)
+	virtual ScriptInstance *instance_create(Object *p_this) override {
+		GDNativePtr<void> ret = nullptr;
+		GDVIRTUAL_REQUIRED_CALL(_instance_create, p_this, ret);
+		return reinterpret_cast<ScriptInstance *>(ret.operator void *());
+	}
+	GDVIRTUAL1RC(GDNativePtr<void>, _placeholder_instance_create, Object *)
+	PlaceHolderScriptInstance *placeholder_instance_create(Object *p_this) override {
+		GDNativePtr<void> ret = nullptr;
+		GDVIRTUAL_REQUIRED_CALL(_placeholder_instance_create, p_this, ret);
+		return reinterpret_cast<PlaceHolderScriptInstance *>(ret.operator void *());
+	}
+
+	EXBIND1RC(bool, instance_has, const Object *)
+	EXBIND0RC(bool, has_source_code)
+	EXBIND0RC(String, get_source_code)
+	EXBIND1(set_source_code, const String &)
+	EXBIND1R(Error, reload, bool)
+
+	GDVIRTUAL0RC(TypedArray<Dictionary>, _get_documentation)
+#ifdef TOOLS_ENABLED
+	virtual Vector<DocData::ClassDoc> get_documentation() const override {
+		TypedArray<Dictionary> doc;
+		GDVIRTUAL_REQUIRED_CALL(_get_documentation, doc);
+
+		Vector<DocData::ClassDoc> class_doc;
+#ifndef _MSC_VER
+#warning missing conversion from documentation to ClassDoc
+#endif
+		return class_doc;
+	}
+#endif // TOOLS_ENABLED
+
+	EXBIND1RC(bool, has_method, const StringName &)
+
+	GDVIRTUAL1RC(Dictionary, _get_method_info, const StringName &)
+	virtual MethodInfo get_method_info(const StringName &p_method) const override {
+		Dictionary mi;
+		GDVIRTUAL_REQUIRED_CALL(_get_method_info, p_method, mi);
+		return MethodInfo::from_dict(mi);
+	}
+
+	EXBIND0RC(bool, is_tool)
+	EXBIND0RC(bool, is_valid)
+
+	EXBIND0RC(ScriptLanguage *, get_language)
+	EXBIND1RC(bool, has_script_signal, const StringName &)
+
+	GDVIRTUAL0RC(TypedArray<Dictionary>, _get_script_signal_list)
+
+	virtual void get_script_signal_list(List<MethodInfo> *r_signals) const override {
+		TypedArray<Dictionary> sl;
+		GDVIRTUAL_REQUIRED_CALL(_get_script_signal_list, sl);
+		for (int i = 0; i < sl.size(); i++) {
+			r_signals->push_back(MethodInfo::from_dict(sl[i]));
+		}
+	}
+
+	GDVIRTUAL1RC(bool, _has_property_default_value, const StringName &)
+	GDVIRTUAL1RC(Variant, _get_property_default_value, const StringName &)
+
+	virtual bool get_property_default_value(const StringName &p_property, Variant &r_value) const override {
+		bool has_dv = false;
+		if (!GDVIRTUAL_REQUIRED_CALL(_has_property_default_value, p_property, has_dv) || !has_dv) {
+			return false;
+		}
+		Variant ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_property_default_value, p_property, ret);
+		return ret;
+	}
+
+	EXBIND0(update_exports)
+
+	GDVIRTUAL0RC(TypedArray<Dictionary>, _get_script_method_list)
+
+	virtual void get_script_method_list(List<MethodInfo> *r_methods) const override {
+		TypedArray<Dictionary> sl;
+		GDVIRTUAL_REQUIRED_CALL(_get_script_method_list, sl);
+		for (int i = 0; i < sl.size(); i++) {
+			r_methods->push_back(MethodInfo::from_dict(sl[i]));
+		}
+	}
+
+	GDVIRTUAL0RC(TypedArray<Dictionary>, _get_script_property_list)
+
+	virtual void get_script_property_list(List<PropertyInfo> *r_propertys) const override {
+		TypedArray<Dictionary> sl;
+		GDVIRTUAL_REQUIRED_CALL(_get_script_property_list, sl);
+		for (int i = 0; i < sl.size(); i++) {
+			r_propertys->push_back(PropertyInfo::from_dict(sl[i]));
+		}
+	}
+
+	EXBIND1RC(int, get_member_line, const StringName &)
+
+	GDVIRTUAL0RC(Dictionary, _get_constants)
+
+	virtual void get_constants(Map<StringName, Variant> *p_constants) override {
+		Dictionary constants;
+		GDVIRTUAL_REQUIRED_CALL(_get_constants, constants);
+		List<Variant> keys;
+		constants.get_key_list(&keys);
+		for (const Variant &K : keys) {
+			p_constants->insert(K, constants[K]);
+		}
+	}
+	GDVIRTUAL0RC(TypedArray<StringName>, _get_members)
+	virtual void get_members(Set<StringName> *p_members) override {
+		TypedArray<StringName> members;
+		GDVIRTUAL_REQUIRED_CALL(_get_members, members);
+		for (int i = 0; i < members.size(); i++) {
+			p_members->insert(members[i]);
+		}
+	}
+
+	EXBIND0RC(bool, is_placeholder_fallback_enabled)
+
+	GDVIRTUAL0RC(TypedArray<Dictionary>, _get_rpc_methods)
+
+	virtual const Vector<Multiplayer::RPCConfig> get_rpc_methods() const override {
+		TypedArray<Dictionary> ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_rpc_methods, ret);
+		Vector<Multiplayer::RPCConfig> rpcret;
+		for (int i = 0; i < ret.size(); i++) {
+			Dictionary d = ret[i];
+			Multiplayer::RPCConfig rpc;
+			ERR_CONTINUE(!d.has("name"));
+			rpc.name = d["name"];
+			ERR_CONTINUE(!d.has("rpc_mode"));
+			rpc.rpc_mode = Multiplayer::RPCMode(int(d["rpc_mode"]));
+			ERR_CONTINUE(!d.has("call_local"));
+			rpc.call_local = d["call_local"];
+			ERR_CONTINUE(!d.has("transfer_mode"));
+			rpc.transfer_mode = Multiplayer::TransferMode(int(d["transfer_mode"]));
+			ERR_CONTINUE(!d.has("channel"));
+			rpc.channel = d["channel"];
+			rpcret.push_back(rpc);
+		}
+		return rpcret;
+	}
+
+	ScriptExtension() {}
+};
+
+typedef ScriptLanguage::ProfilingInfo ScriptLanguageExtensionProfilingInfo;
+
+GDVIRTUAL_NATIVE_PTR(ScriptLanguageExtensionProfilingInfo)
+
+class ScriptLanguageExtension : public ScriptLanguage {
+	GDCLASS(ScriptLanguageExtension, ScriptLanguage)
+protected:
+	static void _bind_methods();
+
+public:
+	EXBIND0RC(String, get_name)
+
+	EXBIND0(init)
+	EXBIND0RC(String, get_type)
+	EXBIND0RC(String, get_extension)
+	EXBIND1R(Error, execute_file, const String &)
+	EXBIND0(finish)
+
+	/* EDITOR FUNCTIONS */
+
+	GDVIRTUAL0RC(Vector<String>, _get_reserved_words)
+
+	virtual void get_reserved_words(List<String> *p_words) const override {
+		Vector<String> ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_reserved_words, ret);
+		for (int i = 0; i < ret.size(); i++) {
+			p_words->push_back(ret[i]);
+		}
+	}
+	EXBIND1RC(bool, is_control_flow_keyword, String)
+
+	GDVIRTUAL0RC(Vector<String>, _get_comment_delimiters)
+
+	virtual void get_comment_delimiters(List<String> *p_words) const override {
+		Vector<String> ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_comment_delimiters, ret);
+		for (int i = 0; i < ret.size(); i++) {
+			p_words->push_back(ret[i]);
+		}
+	}
+
+	GDVIRTUAL0RC(Vector<String>, _get_string_delimiters)
+
+	virtual void get_string_delimiters(List<String> *p_words) const override {
+		Vector<String> ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_string_delimiters, ret);
+		for (int i = 0; i < ret.size(); i++) {
+			p_words->push_back(ret[i]);
+		}
+	}
+
+	EXBIND3RC(Ref<Script>, make_template, const String &, const String &, const String &)
+
+	GDVIRTUAL1RC(TypedArray<Dictionary>, _get_built_in_templates, StringName)
+
+	virtual Vector<ScriptTemplate> get_built_in_templates(StringName p_object) override {
+		TypedArray<Dictionary> ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_built_in_templates, p_object, ret);
+		Vector<ScriptTemplate> stret;
+		for (int i = 0; i < ret.size(); i++) {
+			Dictionary d = ret[i];
+			ScriptTemplate st;
+			ERR_CONTINUE(!d.has("inherit"));
+			st.inherit = d["inherit"];
+			ERR_CONTINUE(!d.has("name"));
+			st.name = d["name"];
+			ERR_CONTINUE(!d.has("description"));
+			st.description = d["description"];
+			ERR_CONTINUE(!d.has("content"));
+			st.content = d["content"];
+			ERR_CONTINUE(!d.has("id"));
+			st.id = d["id"];
+			ERR_CONTINUE(!d.has("origin"));
+			st.origin = TemplateLocation(int(d["origin"]));
+			stret.push_back(st);
+		}
+		return stret;
+	}
+
+	EXBIND0R(bool, is_using_templates)
+
+	GDVIRTUAL6RC(Dictionary, _validate, const String &, const String &, bool, bool, bool, bool)
+	virtual bool validate(const String &p_script, const String &p_path = "", List<String> *r_functions = nullptr, List<ScriptError> *r_errors = nullptr, List<Warning> *r_warnings = nullptr, Set<int> *r_safe_lines = nullptr) const override {
+		Dictionary ret;
+		GDVIRTUAL_REQUIRED_CALL(_validate, p_script, p_path, r_functions != nullptr, r_errors != nullptr, r_warnings != nullptr, r_safe_lines != nullptr, ret);
+		if (!ret.has("valid")) {
+			return false;
+		}
+		if (r_functions != nullptr && ret.has("functions")) {
+			Vector<String> functions = ret["functions"];
+			for (int i = 0; i < functions.size(); i++) {
+				r_functions->push_back(functions[i]);
+			}
+		}
+		if (r_errors != nullptr && ret.has("errors")) {
+			Array errors = ret["errors"];
+			for (int i = 0; i < errors.size(); i++) {
+				Dictionary err = errors[i];
+				ERR_CONTINUE(!err.has("line"));
+				ERR_CONTINUE(!err.has("column"));
+				ERR_CONTINUE(!err.has("message"));
+
+				ScriptError serr;
+				serr.line = err["line"];
+				serr.column = err["column"];
+				serr.message = err["message"];
+
+				r_errors->push_back(serr);
+			}
+		}
+		if (r_warnings != nullptr && ret.has("warnings")) {
+			ERR_FAIL_COND_V(!ret.has("warnings"), false);
+			Array warnings = ret["warnings"];
+			for (int i = 0; i < warnings.size(); i++) {
+				Dictionary warn = warnings[i];
+				ERR_CONTINUE(!warn.has("start_line"));
+				ERR_CONTINUE(!warn.has("end_line"));
+				ERR_CONTINUE(!warn.has("leftmost_column"));
+				ERR_CONTINUE(!warn.has("rightmost_column"));
+				ERR_CONTINUE(!warn.has("code"));
+				ERR_CONTINUE(!warn.has("string_code"));
+				ERR_CONTINUE(!warn.has("message"));
+
+				Warning swarn;
+				swarn.start_line = warn["start_line"];
+				swarn.end_line = warn["end_line"];
+				swarn.leftmost_column = warn["leftmost_column"];
+				swarn.rightmost_column = warn["rightmost_column"];
+				swarn.code = warn["code"];
+				swarn.string_code = warn["string_code"];
+				swarn.message = warn["message"];
+
+				r_warnings->push_back(swarn);
+			}
+		}
+		if (r_safe_lines != nullptr && ret.has("safe_lines")) {
+			PackedInt32Array safe_lines = ret["safe_lines"];
+			for (int i = 0; i < safe_lines.size(); i++) {
+				r_safe_lines->insert(safe_lines[i]);
+			}
+		}
+		return ret["valid"];
+	}
+
+	EXBIND1RC(String, validate_path, const String &)
+	GDVIRTUAL0RC(Object *, _create_script)
+	Script *create_script() const override {
+		Object *ret = nullptr;
+		GDVIRTUAL_REQUIRED_CALL(_create_script, ret);
+		return Object::cast_to<Script>(ret);
+	}
+	EXBIND0RC(bool, has_named_classes)
+	EXBIND0RC(bool, supports_builtin_mode)
+	EXBIND0RC(bool, supports_documentation)
+	EXBIND0RC(bool, can_inherit_from_file)
+
+	EXBIND2RC(int, find_function, const String &, const String &)
+	EXBIND3RC(String, make_function, const String &, const String &, const PackedStringArray &)
+	EXBIND3R(Error, open_in_external_editor, const Ref<Script> &, int, int)
+	EXBIND0R(bool, overrides_external_editor)
+
+	GDVIRTUAL3RC(Dictionary, _complete_code, const String &, const String &, Object *)
+
+	virtual Error complete_code(const String &p_code, const String &p_path, Object *p_owner, List<CodeCompletionOption> *r_options, bool &r_force, String &r_call_hint) override {
+		Dictionary ret;
+		GDVIRTUAL_REQUIRED_CALL(_complete_code, p_code, p_path, p_owner, ret);
+		if (!ret.has("result")) {
+			return ERR_UNAVAILABLE;
+		}
+
+		if (r_options != nullptr && ret.has("options")) {
+			Array options = ret["options"];
+			for (int i = 0; i < options.size(); i++) {
+				Dictionary op = options[i];
+				CodeCompletionOption option;
+				ERR_CONTINUE(!op.has("kind"));
+				option.kind = CodeCompletionKind(int(op["kind"]));
+				ERR_CONTINUE(!op.has("display"));
+				option.display = op["display"];
+				ERR_CONTINUE(!op.has("insert_text"));
+				option.insert_text = op["insert_text"];
+				ERR_CONTINUE(!op.has("font_color"));
+				option.font_color = op["font_color"];
+				ERR_CONTINUE(!op.has("icon"));
+				option.icon = op["icon"];
+				ERR_CONTINUE(!op.has("default_value"));
+				option.default_value = op["default_value"];
+				if (op.has("matches")) {
+					PackedInt32Array matches = op["matches"];
+					ERR_CONTINUE(matches.size() & 1);
+					for (int j = 0; j < matches.size(); j += 2) {
+						option.matches.push_back(Pair<int, int>(matches[j], matches[j + 1]));
+					}
+				}
+				r_options->push_back(option);
+			}
+		}
+
+		ERR_FAIL_COND_V(!ret.has("force"), ERR_UNAVAILABLE);
+		r_force = ret["force"];
+		ERR_FAIL_COND_V(!ret.has("call_hint"), ERR_UNAVAILABLE);
+		r_call_hint = ret["call_hint"];
+		ERR_FAIL_COND_V(!ret.has("result"), ERR_UNAVAILABLE);
+		Error result = Error(int(ret["result"]));
+
+		return result;
+	}
+
+	GDVIRTUAL4RC(Dictionary, _lookup_code, const String &, const String &, const String &, Object *)
+
+	virtual Error lookup_code(const String &p_code, const String &p_symbol, const String &p_path, Object *p_owner, LookupResult &r_result) override {
+		Dictionary ret;
+		GDVIRTUAL_REQUIRED_CALL(_lookup_code, p_code, p_symbol, p_path, p_owner, ret);
+		if (!ret.has("result")) {
+			return ERR_UNAVAILABLE;
+		}
+
+		ERR_FAIL_COND_V(!ret.has("type"), ERR_UNAVAILABLE);
+		r_result.type = LookupResultType(int(ret["type"]));
+		ERR_FAIL_COND_V(!ret.has("script"), ERR_UNAVAILABLE);
+		r_result.script = ret["script"];
+		ERR_FAIL_COND_V(!ret.has("class_name"), ERR_UNAVAILABLE);
+		r_result.class_name = ret["class_name"];
+		ERR_FAIL_COND_V(!ret.has("class_path"), ERR_UNAVAILABLE);
+		r_result.class_path = ret["class_path"];
+		ERR_FAIL_COND_V(!ret.has("location"), ERR_UNAVAILABLE);
+		r_result.location = ret["location"];
+
+		Error result = Error(int(ret["result"]));
+
+		return result;
+	}
+
+	GDVIRTUAL3RC(String, _auto_indent_code, const String &, int, int)
+	virtual void auto_indent_code(String &p_code, int p_from_line, int p_to_line) const override {
+		String ret;
+		GDVIRTUAL_REQUIRED_CALL(_auto_indent_code, p_code, p_from_line, p_to_line, ret);
+		p_code = ret;
+	}
+	EXBIND2(add_global_constant, const StringName &, const Variant &)
+	EXBIND2(add_named_global_constant, const StringName &, const Variant &)
+	EXBIND1(remove_named_global_constant, const StringName &)
+
+	/* MULTITHREAD FUNCTIONS */
+
+	//some VMs need to be notified of thread creation/exiting to allocate a stack
+	EXBIND0(thread_enter)
+	EXBIND0(thread_exit)
+
+	EXBIND0RC(String, debug_get_error)
+	EXBIND0RC(int, debug_get_stack_level_count)
+	EXBIND1RC(int, debug_get_stack_level_line, int)
+	EXBIND1RC(String, debug_get_stack_level_function, int)
+	EXBIND1RC(String, debug_get_stack_level_source, int)
+
+	GDVIRTUAL3R(Dictionary, _debug_get_stack_level_locals, int, int, int)
+	virtual void debug_get_stack_level_locals(int p_level, List<String> *p_locals, List<Variant> *p_values, int p_max_subitems = -1, int p_max_depth = -1) override {
+		Dictionary ret;
+		GDVIRTUAL_REQUIRED_CALL(_debug_get_stack_level_locals, p_level, p_max_subitems, p_max_depth, ret);
+		if (ret.size() == 0) {
+			return;
+		}
+		if (p_locals != nullptr && ret.has("locals")) {
+			PackedStringArray strings = ret["locals"];
+			for (int i = 0; i < strings.size(); i++) {
+				p_locals->push_back(strings[i]);
+			}
+		}
+		if (p_values != nullptr && ret.has("values")) {
+			Array values = ret["values"];
+			for (int i = 0; i < values.size(); i++) {
+				p_values->push_back(values[i]);
+			}
+		}
+	}
+	GDVIRTUAL3R(Dictionary, _debug_get_stack_level_members, int, int, int)
+	virtual void debug_get_stack_level_members(int p_level, List<String> *p_members, List<Variant> *p_values, int p_max_subitems = -1, int p_max_depth = -1) override {
+		Dictionary ret;
+		GDVIRTUAL_REQUIRED_CALL(_debug_get_stack_level_members, p_level, p_max_subitems, p_max_depth, ret);
+		if (ret.size() == 0) {
+			return;
+		}
+		if (p_members != nullptr && ret.has("members")) {
+			PackedStringArray strings = ret["members"];
+			for (int i = 0; i < strings.size(); i++) {
+				p_members->push_back(strings[i]);
+			}
+		}
+		if (p_values != nullptr && ret.has("values")) {
+			Array values = ret["values"];
+			for (int i = 0; i < values.size(); i++) {
+				p_values->push_back(values[i]);
+			}
+		}
+	}
+	GDVIRTUAL1R(GDNativePtr<void>, _debug_get_stack_level_instance, int)
+
+	virtual ScriptInstance *debug_get_stack_level_instance(int p_level) override {
+		GDNativePtr<void> ret = nullptr;
+		GDVIRTUAL_REQUIRED_CALL(_debug_get_stack_level_instance, p_level, ret);
+		return reinterpret_cast<ScriptInstance *>(ret.operator void *());
+	}
+	GDVIRTUAL2R(Dictionary, _debug_get_globals, int, int)
+	virtual void debug_get_globals(List<String> *p_globals, List<Variant> *p_values, int p_max_subitems = -1, int p_max_depth = -1) override {
+		Dictionary ret;
+		GDVIRTUAL_REQUIRED_CALL(_debug_get_globals, p_max_subitems, p_max_depth, ret);
+		if (ret.size() == 0) {
+			return;
+		}
+		if (p_globals != nullptr && ret.has("globals")) {
+			PackedStringArray strings = ret["globals"];
+			for (int i = 0; i < strings.size(); i++) {
+				p_globals->push_back(strings[i]);
+			}
+		}
+		if (p_values != nullptr && ret.has("values")) {
+			Array values = ret["values"];
+			for (int i = 0; i < values.size(); i++) {
+				p_values->push_back(values[i]);
+			}
+		}
+	}
+
+	EXBIND4R(String, debug_parse_stack_level_expression, int, const String &, int, int)
+
+	GDVIRTUAL0R(TypedArray<Dictionary>, _debug_get_current_stack_info)
+	virtual Vector<StackInfo> debug_get_current_stack_info() override {
+		TypedArray<Dictionary> ret;
+		GDVIRTUAL_REQUIRED_CALL(_debug_get_current_stack_info, ret);
+		Vector<StackInfo> sret;
+		for (int i = 0; i < ret.size(); i++) {
+			StackInfo si;
+			Dictionary d = ret[i];
+			ERR_CONTINUE(!d.has("file"));
+			ERR_CONTINUE(!d.has("func"));
+			ERR_CONTINUE(!d.has("line"));
+			si.file = d["file"];
+			si.func = d["func"];
+			si.line = d["line"];
+			sret.push_back(si);
+		}
+		return sret;
+	}
+
+	EXBIND0(reload_all_scripts)
+	EXBIND2(reload_tool_script, const Ref<Script> &, bool)
+	/* LOADER FUNCTIONS */
+
+	GDVIRTUAL0RC(PackedStringArray, _get_recognized_extensions)
+
+	virtual void get_recognized_extensions(List<String> *p_extensions) const override {
+		PackedStringArray ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_recognized_extensions, ret);
+		for (int i = 0; i < ret.size(); i++) {
+			p_extensions->push_back(ret[i]);
+		}
+	}
+
+	GDVIRTUAL0RC(TypedArray<Dictionary>, _get_public_functions)
+	virtual void get_public_functions(List<MethodInfo> *p_functions) const override {
+		TypedArray<Dictionary> ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_public_functions, ret);
+		for (int i = 0; i < ret.size(); i++) {
+			MethodInfo mi = MethodInfo::from_dict(ret[i]);
+			p_functions->push_back(mi);
+		}
+	}
+	GDVIRTUAL0RC(Dictionary, _get_public_constants)
+	virtual void get_public_constants(List<Pair<String, Variant>> *p_constants) const override {
+		Dictionary ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_public_constants, ret);
+		for (int i = 0; i < ret.size(); i++) {
+			Dictionary d = ret[i];
+			ERR_CONTINUE(!d.has("name"));
+			ERR_CONTINUE(!d.has("value"));
+			p_constants->push_back(Pair<String, Variant>(d["name"], d["value"]));
+		}
+	}
+
+	EXBIND0(profiling_start)
+	EXBIND0(profiling_stop)
+
+	GDVIRTUAL2R(int, _profiling_get_accumulated_data, GDNativePtr<ScriptLanguageExtensionProfilingInfo>, int)
+
+	virtual int profiling_get_accumulated_data(ProfilingInfo *p_info_arr, int p_info_max) override {
+		int ret = 0;
+		GDVIRTUAL_REQUIRED_CALL(_profiling_get_accumulated_data, p_info_arr, p_info_max, ret);
+		return ret;
+	}
+
+	GDVIRTUAL2R(int, _profiling_get_frame_data, GDNativePtr<ScriptLanguageExtensionProfilingInfo>, int)
+
+	virtual int profiling_get_frame_data(ProfilingInfo *p_info_arr, int p_info_max) override {
+		int ret = 0;
+		GDVIRTUAL_REQUIRED_CALL(_profiling_get_accumulated_data, p_info_arr, p_info_max, ret);
+		return ret;
+	}
+
+	GDVIRTUAL1R(GDNativePtr<void>, _alloc_instance_binding_data, Object *)
+
+	virtual void *alloc_instance_binding_data(Object *p_object) override {
+		GDNativePtr<void> ret = nullptr;
+		GDVIRTUAL_REQUIRED_CALL(_alloc_instance_binding_data, p_object, ret);
+		return ret.operator void *();
+	}
+
+	GDVIRTUAL1(_free_instance_binding_data, GDNativePtr<void>)
+
+	virtual void free_instance_binding_data(void *p_data) override {
+		GDVIRTUAL_REQUIRED_CALL(_free_instance_binding_data, p_data);
+	}
+
+	EXBIND1(refcount_incremented_instance_binding, Object *)
+	EXBIND1R(bool, refcount_decremented_instance_binding, Object *)
+
+	EXBIND0(frame)
+
+	EXBIND1RC(bool, handles_global_class_type, const String &)
+
+	GDVIRTUAL1RC(Dictionary, _get_global_class_name, const String &)
+
+	virtual String get_global_class_name(const String &p_path, String *r_base_type = nullptr, String *r_icon_path = nullptr) const override {
+		Dictionary ret;
+		GDVIRTUAL_REQUIRED_CALL(_get_global_class_name, p_path, ret);
+		if (!ret.has("name")) {
+			return String();
+		}
+		if (r_base_type != nullptr && ret.has("base_type")) {
+			*r_base_type = ret["base_type"];
+		}
+		if (r_icon_path != nullptr && ret.has("icon_path")) {
+			*r_icon_path = ret["icon_path"];
+		}
+		return ret["name"];
+	}
+};
+
+VARIANT_ENUM_CAST(ScriptLanguageExtension::LookupResultType)
+VARIANT_ENUM_CAST(ScriptLanguageExtension::CodeCompletionKind)
+
+class ScriptInstanceExtension : public ScriptInstance {
+public:
+	const GDNativeExtensionScriptInstanceInfo *native_info;
+	GDNativeExtensionScriptInstanceDataPtr instance = nullptr;
+
+// There should not be warnings on explicit casts.
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wignored-qualifiers"
+#endif
+
+	virtual bool set(const StringName &p_name, const Variant &p_value) override {
+		if (native_info->set_func) {
+			return native_info->set_func(instance, (const GDNativeStringNamePtr)&p_name, (const GDNativeVariantPtr)&p_value);
+		}
+		return false;
+	}
+	virtual bool get(const StringName &p_name, Variant &r_ret) const override {
+		if (native_info->get_func) {
+			return native_info->get_func(instance, (const GDNativeStringNamePtr)&p_name, (GDNativeVariantPtr)&r_ret);
+		}
+		return false;
+	}
+	virtual void get_property_list(List<PropertyInfo> *p_list) const override {
+		if (native_info->get_property_list_func) {
+			uint32_t pcount;
+			const GDNativePropertyInfo *pinfo = native_info->get_property_list_func(instance, &pcount);
+			for (uint32_t i = 0; i < pcount; i++) {
+				p_list->push_back(PropertyInfo(Variant::Type(pinfo[i].type), pinfo[i].class_name, PropertyHint(pinfo[i].hint), pinfo[i].hint_string, pinfo[i].usage, pinfo[i].class_name));
+			}
+			if (native_info->free_property_list_func) {
+				native_info->free_property_list_func(instance, pinfo);
+			}
+		}
+	}
+	virtual Variant::Type get_property_type(const StringName &p_name, bool *r_is_valid = nullptr) const override {
+		if (native_info->get_property_type_func) {
+			GDNativeBool is_valid = 0;
+			GDNativeVariantType type = native_info->get_property_type_func(instance, (const GDNativeStringNamePtr)&p_name, &is_valid);
+			if (r_is_valid) {
+				*r_is_valid = is_valid != 0;
+			}
+
+			return Variant::Type(type);
+		}
+		return Variant::NIL;
+	}
+
+	virtual Object *get_owner() override {
+		if (native_info->get_owner_func) {
+			return (Object *)native_info->get_owner_func(instance);
+		}
+		return nullptr;
+	}
+	static void _add_property_with_state(const GDNativeStringNamePtr p_name, const GDNativeVariantPtr p_value, void *p_userdata) {
+		List<Pair<StringName, Variant>> *state = (List<Pair<StringName, Variant>> *)p_userdata;
+		state->push_back(Pair<StringName, Variant>(*(const StringName *)p_name, *(const Variant *)p_value));
+	}
+	virtual void get_property_state(List<Pair<StringName, Variant>> &state) override {
+		if (native_info->get_property_state_func) {
+			native_info->get_property_state_func(instance, _add_property_with_state, &state);
+		}
+	}
+
+	virtual void get_method_list(List<MethodInfo> *p_list) const override {
+		if (native_info->get_method_list_func) {
+			uint32_t mcount;
+			const GDNativeMethodInfo *minfo = native_info->get_method_list_func(instance, &mcount);
+			for (uint32_t i = 0; i < mcount; i++) {
+				MethodInfo m;
+				m.name = minfo[i].name;
+				m.flags = minfo[i].flags;
+				m.id = minfo[i].id;
+				m.return_val = PropertyInfo(Variant::Type(minfo[i].return_value.type), minfo[i].return_value.class_name, PropertyHint(minfo[i].return_value.hint), minfo[i].return_value.hint_string, minfo[i].return_value.usage, minfo[i].return_value.class_name);
+				for (uint32_t j = 0; j < minfo[i].argument_count; j++) {
+					m.arguments.push_back(PropertyInfo(Variant::Type(minfo[i].arguments[j].type), minfo[i].arguments[j].class_name, PropertyHint(minfo[i].arguments[j].hint), minfo[i].arguments[j].hint_string, minfo[i].arguments[j].usage, minfo[i].arguments[j].class_name));
+				}
+				const Variant *def_values = (const Variant *)minfo[i].default_arguments;
+				for (uint32_t j = 0; j < minfo[i].default_argument_count; j++) {
+					m.default_arguments.push_back(def_values[j]);
+				}
+				p_list->push_back(m);
+			}
+			if (native_info->free_method_list_func) {
+				native_info->free_method_list_func(instance, minfo);
+			}
+		}
+	}
+	virtual bool has_method(const StringName &p_method) const override {
+		if (native_info->has_method_func) {
+			return native_info->has_method_func(instance, (GDNativeStringNamePtr)&p_method);
+		}
+		return false;
+	}
+
+	virtual Variant callp(const StringName &p_method, const Variant **p_args, int p_argcount, Callable::CallError &r_error) override {
+		Variant ret;
+		if (native_info->call_func) {
+			GDNativeCallError ce;
+			native_info->call_func(instance, (const GDNativeStringNamePtr)&p_method, (const GDNativeVariantPtr *)p_args, p_argcount, (GDNativeVariantPtr)&ret, &ce);
+			r_error.error = Callable::CallError::Error(ce.error);
+			r_error.argument = ce.argument;
+			r_error.expected = ce.expected;
+		}
+		return ret;
+	}
+
+	virtual void notification(int p_notification) override {
+		if (native_info->notification_func) {
+			native_info->notification_func(instance, p_notification);
+		}
+	}
+	virtual String to_string(bool *r_valid) override {
+		if (native_info->to_string_func) {
+			GDNativeBool valid;
+			String ret = native_info->to_string_func(instance, &valid);
+			if (r_valid) {
+				*r_valid = valid != 0;
+			}
+			return ret;
+		}
+		return String();
+	}
+
+	virtual void refcount_incremented() override {
+		if (native_info->refcount_incremented_func) {
+			native_info->refcount_incremented_func(instance);
+		}
+	}
+	virtual bool refcount_decremented() override {
+		if (native_info->refcount_decremented_func) {
+			return native_info->refcount_decremented_func(instance);
+		}
+		return false;
+	}
+
+	virtual Ref<Script> get_script() const override {
+		if (native_info->get_script_func) {
+			GDNativeObjectPtr script = native_info->get_script_func(instance);
+			return Ref<Script>(reinterpret_cast<Script *>(script));
+		}
+		return Ref<Script>();
+	}
+
+	virtual bool is_placeholder() const override {
+		if (native_info->is_placeholder_func) {
+			return native_info->is_placeholder_func(instance);
+		}
+		return false;
+	}
+
+	virtual void property_set_fallback(const StringName &p_name, const Variant &p_value, bool *r_valid) override {
+		if (native_info->set_fallback_func) {
+			bool ret = native_info->set_fallback_func(instance, (const GDNativeStringNamePtr)&p_name, (const GDNativeVariantPtr)&p_value);
+			if (r_valid) {
+				*r_valid = ret;
+			}
+		}
+	}
+	virtual Variant property_get_fallback(const StringName &p_name, bool *r_valid) override {
+		Variant ret;
+		if (native_info->get_fallback_func) {
+			bool valid = native_info->get_fallback_func(instance, (const GDNativeStringNamePtr)&p_name, (GDNativeVariantPtr)&ret);
+			if (r_valid) {
+				*r_valid = valid;
+			}
+		}
+		return ret;
+	}
+
+	virtual ScriptLanguage *get_language() override {
+		if (native_info->get_language_func) {
+			GDNativeExtensionScriptLanguagePtr lang = native_info->get_language_func(instance);
+			return reinterpret_cast<ScriptLanguage *>(lang);
+		}
+		return nullptr;
+		;
+	}
+	virtual ~ScriptInstanceExtension() {
+		if (native_info->free_func) {
+			native_info->free_func(instance);
+		}
+	}
+
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
+};
+
+#endif // SCRIPT_LANGUAGE_EXTENSION_H
diff --git a/core/register_core_types.cpp b/core/register_core_types.cpp
index 1a306e88fc..415b56cd83 100644
--- a/core/register_core_types.cpp
+++ b/core/register_core_types.cpp
@@ -71,6 +71,7 @@
 #include "core/multiplayer/multiplayer_api.h"
 #include "core/multiplayer/multiplayer_peer.h"
 #include "core/object/class_db.h"
+#include "core/object/script_language_extension.h"
 #include "core/object/undo_redo.h"
 #include "core/os/main_loop.h"
 #include "core/os/time.h"
@@ -142,6 +143,10 @@ void register_core_types() {
 	GDREGISTER_CLASS(Object);
 
 	GDREGISTER_ABSTRACT_CLASS(Script);
+	GDREGISTER_ABSTRACT_CLASS(ScriptLanguage);
+
+	GDREGISTER_VIRTUAL_CLASS(ScriptExtension);
+	GDREGISTER_VIRTUAL_CLASS(ScriptLanguageExtension);
 
 	GDREGISTER_CLASS(RefCounted);
 	GDREGISTER_CLASS(WeakRef);
@@ -263,6 +268,7 @@ void register_core_types() {
 	_engine_debugger = memnew(core_bind::EngineDebugger);
 
 	GDREGISTER_NATIVE_STRUCT(AudioFrame, "float left;float right");
+	GDREGISTER_NATIVE_STRUCT(ScriptLanguageExtensionProfilingInfo, "StringName signature;uint64_t call_count;uint64_t total_time;uint64_t self_time");
 }
 
 void register_core_settings() {