Switch from Sentinel types to Enums

pgjones commented 2 years ago

The latter are much easier to work with when type hinting and can be used successfully with mypyc, whereas the former are sadly very difficult in both aspects.

This loses the nice property of type(NEED_DATA) is NEED_DATA (as expanded on in the deleted docs section). However, I don't think this is widely used in practice.

Closes #153. See also #8 for reasoning behind the introduction of the type property.

@njsmith what do you think about this?

tomchristie commented 2 years ago

This looks to me like a breaking API change that would impact Uvicorn and HTTPX.

I do prefer the API, tho.

Kludex commented 2 years ago

I can check this on Uvicorn tonight. jfyk

tomchristie commented 2 years ago

@Kludex Sure thing. Permalinks to relevant parts of code in the comment above. (Tho I can see that's not obvious.)

Kludex commented 1 year ago

This was merged on httpcore: https://github.com/encode/httpcore/pull/579

Kludex commented 1 year ago

The only problem on uvicorn was:

            event = h11.InformationalResponse(
                status_code=100, headers=[], reason="Continue"
            )

Issue:

uvicorn/protocols/http/h11_impl.py:537: error: Argument "headers" to "InformationalResponse" has incompatible type "List[<nothing>]"; expected "Union[Headers, List[Tuple[bytes, bytes]], List[Tuple[str, str]]]"  [arg-type]
uvicorn/protocols/http/h11_impl.py:537: note: "List" is invariant -- see https://mypy.readthedocs.io/en/stable/common_issues.html#variance
uvicorn/protocols/http/h11_impl.py:537: note: Consider using "Sequence" instead, which is covariant
Found 1 error in 1 file (checked 53 source files)

I've used this branch on uvicorn to check the changes I'd need: https://github.com/encode/uvicorn/pull/1744/files

python-hyper / h11

Switch from Sentinel types to Enums #154