diff --git a/core/script_language.h b/core/script_language.h
index b2dab666c4f7..b0c60b4e904f 100644
--- a/core/script_language.h
+++ b/core/script_language.h
@@ -250,7 +250,7 @@ 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_base_path, Object *p_owner, List<String> *r_options, bool &r_force, String &r_call_hint) { return ERR_UNAVAILABLE; }
+	virtual Error complete_code(const String &p_code, const String &p_path, Object *p_owner, List<String> *r_options, bool &r_force, String &r_call_hint) { return ERR_UNAVAILABLE; }
 
 	struct LookupResult {
 		enum Type {
@@ -269,7 +269,7 @@ public:
 		int location;
 	};
 
-	virtual Error lookup_code(const String &p_code, const String &p_symbol, const String &p_base_path, Object *p_owner, LookupResult &r_result) { return ERR_UNAVAILABLE; }
+	virtual Error lookup_code(const String &p_code, const String &p_symbol, const String &p_path, Object *p_owner, LookupResult &r_result) { return ERR_UNAVAILABLE; }
 
 	virtual void auto_indent_code(String &p_code, int p_from_line, int p_to_line) const = 0;
 	virtual void add_global_constant(const StringName &p_variable, const Variant &p_value) = 0;
diff --git a/editor/plugins/script_text_editor.cpp b/editor/plugins/script_text_editor.cpp
index f66ae0465fe4..1fe4ac1372ed 100644
--- a/editor/plugins/script_text_editor.cpp
+++ b/editor/plugins/script_text_editor.cpp
@@ -735,7 +735,7 @@ void ScriptTextEditor::_code_complete_script(const String &p_code, List<String>
 		base = _find_node_for_script(base, base, script);
 	}
 	String hint;
-	Error err = script->get_language()->complete_code(p_code, script->get_path().get_base_dir(), base, r_options, r_force, hint);
+	Error err = script->get_language()->complete_code(p_code, script->get_path(), base, r_options, r_force, hint);
 	if (err == OK && hint != "") {
 		code_editor->get_text_edit()->set_code_hint(hint);
 	}
@@ -766,7 +766,7 @@ void ScriptTextEditor::_lookup_symbol(const String &p_symbol, int p_row, int p_c
 			EditorNode::get_singleton()->load_resource(p_symbol);
 		}
 
-	} else if (script->get_language()->lookup_code(code_editor->get_text_edit()->get_text_for_lookup_completion(), p_symbol, script->get_path().get_base_dir(), base, result) == OK) {
+	} else if (script->get_language()->lookup_code(code_editor->get_text_edit()->get_text_for_lookup_completion(), p_symbol, script->get_path(), base, result) == OK) {
 
 		_goto_line(p_row);
 
@@ -1447,7 +1447,7 @@ void ScriptTextEditor::_text_edit_gui_input(const Ref<InputEvent> &ev) {
 					base = _find_node_for_script(base, base, script);
 				}
 				ScriptLanguage::LookupResult result;
-				if (script->get_language()->lookup_code(code_editor->get_text_edit()->get_text_for_lookup_completion(), word_at_mouse, script->get_path().get_base_dir(), base, result) == OK) {
+				if (script->get_language()->lookup_code(code_editor->get_text_edit()->get_text_for_lookup_completion(), word_at_mouse, script->get_path(), base, result) == OK) {
 					open_docs = true;
 				}
 			}
diff --git a/modules/gdnative/include/pluginscript/godot_pluginscript.h b/modules/gdnative/include/pluginscript/godot_pluginscript.h
index 968f91ae9f85..a9e83d15244a 100644
--- a/modules/gdnative/include/pluginscript/godot_pluginscript.h
+++ b/modules/gdnative/include/pluginscript/godot_pluginscript.h
@@ -136,7 +136,7 @@ typedef struct {
 	godot_bool (*validate)(godot_pluginscript_language_data *p_data, const godot_string *p_script, int *r_line_error, int *r_col_error, godot_string *r_test_error, const godot_string *p_path, godot_pool_string_array *r_functions);
 	int (*find_function)(godot_pluginscript_language_data *p_data, const godot_string *p_function, const godot_string *p_code); // Can be NULL
 	godot_string (*make_function)(godot_pluginscript_language_data *p_data, const godot_string *p_class, const godot_string *p_name, const godot_pool_string_array *p_args);
-	godot_error (*complete_code)(godot_pluginscript_language_data *p_data, const godot_string *p_code, const godot_string *p_base_path, godot_object *p_owner, godot_array *r_options, godot_bool *r_force, godot_string *r_call_hint);
+	godot_error (*complete_code)(godot_pluginscript_language_data *p_data, const godot_string *p_code, const godot_string *p_path, godot_object *p_owner, godot_array *r_options, godot_bool *r_force, godot_string *r_call_hint);
 	void (*auto_indent_code)(godot_pluginscript_language_data *p_data, godot_string *p_code, int p_from_line, int p_to_line);
 
 	void (*add_global_constant)(godot_pluginscript_language_data *p_data, const godot_string *p_variable, const godot_variant *p_value);
diff --git a/modules/gdnative/pluginscript/pluginscript_language.cpp b/modules/gdnative/pluginscript/pluginscript_language.cpp
index c9d92c09ede2..7cb47ec62397 100644
--- a/modules/gdnative/pluginscript/pluginscript_language.cpp
+++ b/modules/gdnative/pluginscript/pluginscript_language.cpp
@@ -159,13 +159,13 @@ String PluginScriptLanguage::make_function(const String &p_class, const String &
 	return String();
 }
 
-Error PluginScriptLanguage::complete_code(const String &p_code, const String &p_base_path, Object *p_owner, List<String> *r_options, bool &r_force, String &r_call_hint) {
+Error PluginScriptLanguage::complete_code(const String &p_code, const String &p_path, Object *p_owner, List<String> *r_options, bool &r_force, String &r_call_hint) {
 	if (_desc.complete_code) {
 		Array options;
 		godot_error tmp = _desc.complete_code(
 				_data,
 				(godot_string *)&p_code,
-				(godot_string *)&p_base_path,
+				(godot_string *)&p_path,
 				(godot_object *)p_owner,
 				(godot_array *)&options,
 				&r_force,
diff --git a/modules/gdnative/pluginscript/pluginscript_language.h b/modules/gdnative/pluginscript/pluginscript_language.h
index 991be0bf1284..a11e916975a6 100644
--- a/modules/gdnative/pluginscript/pluginscript_language.h
+++ b/modules/gdnative/pluginscript/pluginscript_language.h
@@ -81,7 +81,7 @@ public:
 	virtual bool can_inherit_from_file() { return true; }
 	virtual int find_function(const String &p_function, const String &p_code) const;
 	virtual String make_function(const String &p_class, const String &p_name, const PoolStringArray &p_args) const;
-	virtual Error complete_code(const String &p_code, const String &p_base_path, Object *p_owner, List<String> *r_options, bool &r_force, String &r_call_hint);
+	virtual Error complete_code(const String &p_code, const String &p_path, Object *p_owner, List<String> *r_options, bool &r_force, String &r_call_hint);
 	virtual void auto_indent_code(String &p_code, int p_from_line, int p_to_line) const;
 	virtual void add_global_constant(const StringName &p_variable, const Variant &p_value);
 
diff --git a/modules/gdscript/gdscript.h b/modules/gdscript/gdscript.h
index 716f536e890f..40b773d99f7a 100644
--- a/modules/gdscript/gdscript.h
+++ b/modules/gdscript/gdscript.h
@@ -458,9 +458,9 @@ public:
 	virtual bool can_inherit_from_file() { return true; }
 	virtual int find_function(const String &p_function, const String &p_code) const;
 	virtual String make_function(const String &p_class, const String &p_name, const PoolStringArray &p_args) const;
-	virtual Error complete_code(const String &p_code, const String &p_base_path, Object *p_owner, List<String> *r_options, bool &r_forced, String &r_call_hint);
+	virtual Error complete_code(const String &p_code, const String &p_path, Object *p_owner, List<String> *r_options, bool &r_forced, String &r_call_hint);
 #ifdef TOOLS_ENABLED
-	virtual Error lookup_code(const String &p_code, const String &p_symbol, const String &p_base_path, Object *p_owner, LookupResult &r_result);
+	virtual Error lookup_code(const String &p_code, const String &p_symbol, const String &p_path, Object *p_owner, LookupResult &r_result);
 #endif
 	virtual String _get_indentation() const;
 	virtual void auto_indent_code(String &p_code, int p_from_line, int p_to_line) const;
diff --git a/modules/gdscript/gdscript_editor.cpp b/modules/gdscript/gdscript_editor.cpp
index fa80c31984b0..6c77968f44fe 100644
--- a/modules/gdscript/gdscript_editor.cpp
+++ b/modules/gdscript/gdscript_editor.cpp
@@ -2461,13 +2461,13 @@ static void _find_call_arguments(GDScriptCompletionContext &p_context, const GDS
 	r_forced = r_result.size() > 0;
 }
 
-Error GDScriptLanguage::complete_code(const String &p_code, const String &p_base_path, Object *p_owner, List<String> *r_options, bool &r_forced, String &r_call_hint) {
+Error GDScriptLanguage::complete_code(const String &p_code, const String &p_path, Object *p_owner, List<String> *r_options, bool &r_forced, String &r_call_hint) {
 
 	const String quote_style = EDITOR_DEF("text_editor/completion/use_single_quotes", false) ? "'" : "\"";
 
 	GDScriptParser parser;
 
-	parser.parse(p_code, p_base_path, false, "", true);
+	parser.parse(p_code, p_path.get_base_dir(), false, p_path, true);
 	r_forced = false;
 	Set<String> options;
 	GDScriptCompletionContext context;
@@ -2478,7 +2478,7 @@ Error GDScriptLanguage::complete_code(const String &p_code, const String &p_base
 
 	if (!context._class || context._class->owner == NULL) {
 		context.base = p_owner;
-		context.base_path = p_base_path;
+		context.base_path = p_path.get_base_dir();
 	}
 
 	bool is_function = false;
@@ -2884,7 +2884,7 @@ Error GDScriptLanguage::complete_code(const String &p_code, const String &p_base
 
 #else
 
-Error GDScriptLanguage::complete_code(const String &p_code, const String &p_base_path, Object *p_owner, List<String> *r_options, bool &r_forced, String &r_call_hint) {
+Error GDScriptLanguage::complete_code(const String &p_code, const String &p_path, Object *p_owner, List<String> *r_options, bool &r_forced, String &r_call_hint) {
 	return OK;
 }
 
@@ -3155,7 +3155,7 @@ static Error _lookup_symbol_from_base(const GDScriptParser::DataType &p_base, co
 	return ERR_CANT_RESOLVE;
 }
 
-Error GDScriptLanguage::lookup_code(const String &p_code, const String &p_symbol, const String &p_base_path, Object *p_owner, LookupResult &r_result) {
+Error GDScriptLanguage::lookup_code(const String &p_code, const String &p_symbol, const String &p_path, Object *p_owner, LookupResult &r_result) {
 
 	//before parsing, try the usual stuff
 	if (ClassDB::class_exists(p_symbol)) {
@@ -3197,7 +3197,7 @@ Error GDScriptLanguage::lookup_code(const String &p_code, const String &p_symbol
 	}
 
 	GDScriptParser parser;
-	parser.parse(p_code, p_base_path, false, "", true);
+	parser.parse(p_code, p_path.get_base_dir(), false, p_path, true);
 
 	if (parser.get_completion_type() == GDScriptParser::COMPLETION_NONE) {
 		return ERR_CANT_RESOLVE;
@@ -3209,7 +3209,7 @@ Error GDScriptLanguage::lookup_code(const String &p_code, const String &p_symbol
 	context.block = parser.get_completion_block();
 	context.line = parser.get_completion_line();
 	context.base = p_owner;
-	context.base_path = p_base_path;
+	context.base_path = p_path.get_base_dir();
 
 	if (context._class && context._class->extends_class.size() > 0) {
 		bool success = false;
diff --git a/modules/gdscript/gdscript_parser.cpp b/modules/gdscript/gdscript_parser.cpp
index 9590009a5485..922ee395dd01 100644
--- a/modules/gdscript/gdscript_parser.cpp
+++ b/modules/gdscript/gdscript_parser.cpp
@@ -3497,7 +3497,7 @@ void GDScriptParser::_parse_class(ClassNode *p_class) {
 					_set_error("'class_name' is only valid for the main class namespace.");
 					return;
 				}
-				if (self_path.empty()) {
+				if (self_path.begins_with("res://") && self_path.find("::") != -1) {
 					_set_error("'class_name' not allowed in built-in scripts.");
 					return;
 				}
diff --git a/modules/mono/csharp_script.h b/modules/mono/csharp_script.h
index e735e0f74180..5525c0a12125 100644
--- a/modules/mono/csharp_script.h
+++ b/modules/mono/csharp_script.h
@@ -380,7 +380,7 @@ public:
 	virtual bool supports_builtin_mode() const;
 	/* TODO? */ virtual int find_function(const String &p_function, const String &p_code) const { return -1; }
 	virtual String make_function(const String &p_class, const String &p_name, const PoolStringArray &p_args) const;
-	/* TODO? */ Error complete_code(const String &p_code, const String &p_base_path, Object *p_owner, List<String> *r_options, String &r_call_hint) { return ERR_UNAVAILABLE; }
+	/* TODO? */ Error complete_code(const String &p_code, const String &p_path, Object *p_owner, List<String> *r_options, String &r_call_hint) { return ERR_UNAVAILABLE; }
 	virtual String _get_indentation() const;
 	/* TODO? */ virtual void auto_indent_code(String &p_code, int p_from_line, int p_to_line) const {}
 	/* TODO */ virtual void add_global_constant(const StringName &p_variable, const Variant &p_value) {}