Type checking for table classes?

[jenskutilek]

I'm using VSCode which does live type checking. In projects involving FontTools, it generates a lot of noise because it can't check the attributes of SFNT table classes.

E.g.

glyf = font["glyf"]
print(sorted(glyf.keys())

Cannot access member keys for "DefaultTable": Member "keys" is unknown.

I've tried adding stubs for the TTFont object, but how can I define that specific keys return specific table classes?

def __getitem__(self, tag: str) -> DefaultTable: ...

BTW I've added the stubs I have so far to this new repo.

[justvanrossum]

TTFont partially behaves like a dict, so I'd expect we should do something like typing.TypedDict, but I'm not sure how to do that for a class implementing the (Mutable)Mapping protocol.

If it's just about suppressing the noise, perhaps use typing.Any instead of DefaultTable.