Ensure subtyping works with erased typevartuples in callables #18408
+44
−4
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅ |
A5rocks
commented
Jan 2, 2025
| ) | ||
| else: | ||
| trivial_varargs = False | ||
|
|
||
| if ( | ||
| right.arg_kinds == [ARG_STAR] | ||
| and isinstance(get_proper_type(right.arg_types[0]), AnyType) |
There was a problem hiding this comment.
I'm pretty sure this check is redundant. It would require updating above to just handle *args: Any and handling tuple[Any, ...] here:
Lines 2164 to 2168 in e05770d
I'm just not sure because the comment says the form isn't constructed by mypy but it's the constructed form of any erased typevartuple? I also don't like treating any given *args: Any as finite length, but I think that ship has sailed.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Fixes #18407
Ironically this is logic directly taken from my other PR #17512. I present this as a seperate PR because now I have a test case for the easier logic -- I'm not pleased with the rest and I think it can be done better (once I have time to think about how to work with constraint logic for a more general solution).
The reason behind these subtyping changes are to allow this subtyping check to pass:
mypy/mypy/constraints.py
Lines 424 to 427 in e05770d
After this, everything works as is typical. I'm pretty sure the reason this passes without the union is because constraints with a callable template don't check subtyping.