Using EditorSyntaxHighlighter in TextEdit crashes the project.

[kitbdev]

Godot version

Godot v4.2.rc (ad72de5)

System information

Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2070 (NVIDIA; 31.0.15.3598) - Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz (12 Threads)

Issue description

The running project crashes without error message if a TextEdit (or CodeEdit) has EditorSyntaxHighlighter set for its syntax_highlighter.

Attaching a debugger to the running project says:

ERROR: Class 'EditorSyntaxHighlighter' can only be instantiated by editor.
   at: ClassDB::instantiate (core\object\class_db.cpp:364)
core\object\class_db.cpp:364 - Class 'EditorSyntaxHighlighter' can only be instantiated by editor.
ERROR: res://addons/eval_command/run_script.tscn:5 - Parse Error: Can't create sub resource of type: EditorSyntaxHighlighter
   at: ResourceLoaderText::load (scene\resources\resource_format_text.cpp:551)
scene\resources\resource_format_text.cpp:551 - res://addons/eval_command/run_script.tscn:5 - Parse Error: Can't create sub resource of type: EditorSyntaxHighlighter
ERROR: Failed loading resource: res://addons/eval_command/run_script.tscn. Make sure resources have been imported by opening the project in the editor at least once.
   at: (core\io\resource_loader.cpp:275)
Failed loading resource: res://addons/eval_command/run_script.tscn. Make sure resources have been imported by opening the project in the editor at least once.
ERROR: Failed loading scene: res://addons/eval_command/run_script.tscn.
   at: (main\main.cpp:3433)
Failed loading scene: res://addons/eval_command/run_script.tscn.

EditorSyntaxHighlighter should probably not be available to select.
Or if EditorSyntaxHighlighter is useful for plugins or something, there should be an error printed when attempting to use it when not in the editor.

Steps to reproduce

Add a TextEdit or a CodeEdit.
Set Highlighting > syntax_highlighter to a new EditorSyntaxHighlighter.
Run the current Scene.
The Scene tries to load and immediately closes.

Minimal reproduction project

N/A

[jsjtxietian]

Yes comfirmed. The error message is pretty clear, what should we do about this? at least it shouldn't crash.

[AThousandShips]

This doesn't crash, it fails to load the main scene, which is unrecoverable, it happens when you can't load other classes as well, I'd say it's to be expected, how would we gracefully recover from this otherwise?

I'm not even sure I'd call this a bug, this is user error

[kitbdev]

It makes sense that it doesn't work, but I think there should be an error message in the Output so it is obvious why.

[AThousandShips]

There is? It says it can't load the scene, if call that obvious:

godot/main/main.cpp

Line 3794 in 655e93d

ERR_FAIL_NULL_V_MSG(scene, EXIT_FAILURE, "Failed loading scene: " + local_game_path + ".");

Maybe we could make it even more obvious to say "exiting game" but it says what is happening

[kitbdev]

Only when there is a console on the running project, nothing is shown in the editor.

[AThousandShips]

That's unrelated to this, that's because the debugger hasn't had a chance to connect yet, that's tracked elsewhere, can't remember the actual issue right now