Correct types for setuptools.setup

[max-muoto]

Fixes #12752

[brianschubert]

Should this be marked @type_check_only? There seems to be some precedence for using it on some similar typeddicts, e.g.

typeshed/stdlib/_locale.pyi

Lines 5 to 6 in 7ccc587

	@type_check_only
	class _LocaleConv(TypedDict):

Also, to bikeshed the name, I see setuptools internally calls this structure a build_info in a few places, so maybe _BuildInfo would be a good fit?

[max-muoto]

Interesting, I wasn't aware of it, but likely what we want here. Thanks for the callout. Agree that's a better name here.

[max-muoto]

f0d929f

[Avasam]

Normally I'd prefer defining such types close to where their implementation stands (so with the appropriate Command or Distribution) but in this case it'd end up in distutils and/or setuptools/_distutils so I guess in setuptools.__init__.py is fine.

I do have a concern using a type-only TypedDict with required members as a parameter: It makes it annoying to use a non-literal dict. Maybe that's ok in setuptools due to the nature of it looking like a config file, it shouldn't be much more complex than my example below?

It's possible, but requires a private type-only import, which isn't great:

from typing import cast, TYPE_CHECKING
if TYPE_CHECKING:
    from setuptools import _BuildInfo

libs = [
    ("lib1", {"sources": []}),
    ("lib2", {"sources": []}),
]
setup(libraries=libs)  # Type error in both mypy and pyright due to missing "sources"
# Ok, but must quote type to avoid runtime error
setup(libraries=cast(list[tuple[str, "_BuildInfo"]], libs))
# Ok
setup(libraries=[("literal", {"sources": []})])
# Ok
libs_annotated: list[tuple[str, "_BuildInfo"]] = [ # Must quote type or use from __future__ import annotations
    ("lib1", {"sources": []}),
    ("lib2", {"sources": []}),
]
setup(libraries=libs_annotated)

[max-muoto]

Yeah, perhaps it's not ideal but I'm not seeing a great alternative, obviously passing things in-line solves this problem, or just:

libs: "list[tuple[str, _BuildInfo]]" = [
    ("lib1", {"sources": []}),
    ("lib2", {"sources": []}),
]
setup(libraries=libs)

Which would work without quotes given deferred annotations.

[Avasam]

At the same time, the kind of people to type-check their setup.py are probably the same going all out on typing (looking at myself here ^^)

[JelleZijlstra]

Are you sure this isn't tuple[str, ...]? In other words, is this really always a one-tuple? (A few more times below.)

[Avasam]

You're right, I also glanced over that...
(same for all definitions below)

[max-muoto]

The one tuple for macros is correct, but the others were a mistake: 2bb4ed4

[Avasam]

Oops, I also glanced over this: tuple[str] means a single-item tuple, we want tuple[str, ...]
https://github.com/python/typeshed/pull/12791/files#r1797961597

[max-muoto]

Oops, I also glanced over this: tuple[str] means a single-item tuple, we want tuple[str, ...] https://github.com/python/typeshed/pull/12791/files#r1797961597

Yep, I assumed they were actually one-tuples from the original issue but it looks like macros is the only one that should be: https://github.com/python/typeshed/pull/12791/files#r1798508136

[max-muoto]

Oops, I also glanced over this: tuple[str] means a single-item tuple, we want tuple[str, ...] https://github.com/python/typeshed/pull/12791/files#r1797961597

Additionally the second value in the tuple can be None: 82ad6cb

Here's a good example of what the types are allowed to be at runtime.

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉