String Enum type should be a union of literal instead of str

[JonathanPlasse]

Description about the feature

In Blender API, there are enum string type, currently the type used is str | int and ideally should only be str (c.f. #213).
Even better would be that the type is a union of possible literal string variant.
For example the return type of bpy.types.Operator.execute() is

The type would be Literal["RUNNING_MODAL"] | Literal["CANCELLED"] | Literal["FINISHED"] | Literal["PASS_THROUGH"] | Literal["INTERFACE"].

Are you willing to contribute about this feature. (Yes/No)

Yes

[nutti]

@JonathanPlasse

I assigned this issue to you.
Do you have an idea about this?
I think this is difficult for our approach to realize this.

[JonathanPlasse]

If the RST contain the link to the enum page in the return type (e.g. Operator Return Items), it should be feasible.
Otherwise, it will be difficult.

[nutti]

I think it is difficult to parse other RST files while processing the document.
If you have an idea, I will remain this issue.
Or, I will close this issue.
What do you think? @JonathanPlasse

[JonathanPlasse]

I would like to take a deeper look to implement it.

[JonathanPlasse]

When encountering an rna enum reference we could parse on the fly the corresponding rst file.

I will see if I can make it work.

[nutti]

Thank you.
This needs to support to read related files from somewhere.

I'm wondering this should be done in transformer or analyzer phase.
https://github.com/nutti/fake-bpy-module/tree/master/src/fake_bpy_module/analyzer
https://github.com/nutti/fake-bpy-module/tree/master/src/fake_bpy_module/transformer

I think adding this feature into the transformer phase is much simpler and easy to maintenance in future.