Repository: godot
Issue: Export Variable's category and grouping (Advanced Exports) with _get_property_list() are not working in Visual Script
Labels: bug,topic:editor,confirmed,topic:visualscript

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https://github.com/godotengine/godot/issues?q=is%3Aissue
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**Godot version:**
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- Godot 3.2.3-stable
- Godot 3.2.4-beta3
- Godot 4 @ [d834789](https://github.com/godotengine/godot/commit/d834789f475d431b10dcaef8804cd75dcd8b47dd)


**OS/device including version:**
<!-- Specify GPU model, drivers, and the backend (GLES2, GLES3, Vulkan) if graphics-related. -->
![Screenshot 2020-12-06 201810](https://user-images.githubusercontent.com/1403194/101296122-793b0a80-3800-11eb-8989-88dcd5dce8fe.jpg)
![Screenshot 2020-12-06 201955](https://user-images.githubusercontent.com/1403194/101296126-7fc98200-3800-11eb-81ac-b5dfbebb91d5.jpg)


**Issue description:**
<!-- What happened, and what was expected. -->
I tried to add categories and groups for my export variables with the __get_property_list()_ function as documented [here](https://docs.godotengine.org/en/stable/getting_started/scripting/gdscript/gdscript_exports.html). I can do it in GDScript but not in Visual Script with the exact same code.

_In Godot 3.2.3-stable and 3.2.4-beta3:_
It's not working at all. And when I closed and reopened the project again, the "make tool" button in the Visual Script editor which was previously set to on would always be off after I reopened the project. I can't add any node to the Visual Script editor unless I disconnected the script from the scene node. Otherwise, it will give me this error:
![Screenshot 2020-12-05 224842a](https://user-images.githubusercontent.com/1403194/101296440-63c6e000-3802-11eb-8f84-ddba39473ca8.jpg)

_In Godot 4 @ [d834789](https://github.com/godotengine/godot/commit/d834789f475d431b10dcaef8804cd75dcd8b47dd):_
It works partially as the variable shows up in the inspector tab. However, the category and group don't show up at all:
![Screenshot 2020-12-06 201034](https://user-images.githubusercontent.com/1403194/101297413-b1921700-3807-11eb-88ad-cc7ad040c229.jpg)

I expect it to work like GDScript and doesn't give me errors:
![Screenshot 2020-12-06 172752](https://user-images.githubusercontent.com/1403194/101297459-e4d4a600-3807-11eb-914f-2651b076a9b0.jpg)


**Steps to reproduce:**

1. Open the script.
2. Add the _get_property_list() function.
3. Calling the functions to add categories, groups, and desired properties (variables) to the inspector tab according to the document [here](https://docs.godotengine.org/en/stable/getting_started/scripting/gdscript/gdscript_exports.html).
4. Check the inspector tab.


**Minimal reproduction project:**
<!-- A small Godot project which reproduces the issue. Drag and drop a zip archive to upload it. -->
For Godot 3:
[test3.zip](https://github.com/godotengine/godot/files/5649828/test3.zip)

For Godot 4 (since some codes have been changed - tool >>> @ tool):
[test4.zip](https://github.com/godotengine/godot/files/5649830/test4.zip)

Edited: Add a new reproduction project for Godot 4 as the old one doesn't compatible with the latest Godot 4 version - v4.0.alpha2.official [79077e6c1] (the engine would crash with the old project file):

[Test4New.zip](https://github.com/godotengine/godot/files/8094461/Test4New.zip)