Add cli paramerter --check-only for script parsing

main/main.cpp

@@ -263,6 +263,7 @@ void Main::print_help(const char *p_binary) {
 
 	OS::get_singleton()->print("Standalone tools:\n");
 	OS::get_singleton()->print("  -s, --script <script>            Run a script.\n");
+	OS::get_singleton()->print("  --check-only                     Only parse for errors and quit (use with --script).\n");
 #ifdef TOOLS_ENABLED
 	OS::get_singleton()->print("  --export <target>                Export the project using the given export target. Export only main pack if path ends with .pck or .zip'.\n");
 	OS::get_singleton()->print("  --export-debug <target>          Like --export, but use debug template.\n");
@@ -1239,6 +1240,7 @@ bool Main::start() {
 	String test;
 	String _export_preset;
 	bool export_debug = false;
+	bool check_only = false;
 
 	main_timer_sync.init(OS::get_singleton()->get_ticks_usec());
 
@@ -1261,6 +1263,8 @@ bool Main::start() {
 			bool parsed_pair = true;
 			if (args[i] == "-s" || args[i] == "--script") {
 				script = args[i + 1];
+			} else if (args[i] == "--check-only") {
+				check_only = true;
 			} else if (args[i] == "--test") {
 				test = args[i + 1];
 #ifdef TOOLS_ENABLED
@@ -1383,6 +1387,10 @@ bool Main::start() {
 		ERR_EXPLAIN("Can't load script: " + script);
 		ERR_FAIL_COND_V(script_res.is_null(), false);
 
+		if (check_only) {
+			return false;
+		}
+
 		if (script_res->can_instance() /*&& script_res->inherits_from("SceneTreeScripted")*/) {
 
 			StringName instance_type = script_res->get_instance_base_type();