Request: Detect redundant overload with keyword-only params
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- Dominant language
- Python
- Stars
- 20.6k
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Description
Feature
I'd like mypy to raise a "overload won't be matched" or "is redundant" or similar for the following two cases:
@overload
def foo(a: str, b: str, c: str): ...
@overload
def foo(a: str, *, b: str, c: str): ... # I believe this is redundant
@overload
def foo(a: str, *, b: str, c: str): ... # I believe this is redundant
@overload
def foo(a: str, b: str, c: str): ...
Pitch
Redundant or unreachable overloads are a code smell revealing either an error that slipped by or a misunderstanding of overloads. This is already raised with simpler signatures.
Example from a typeshed PR where a redundant overload was accidentally left in: https://github.com/python/typeshed/pull/10706#discussion_r1334910025
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
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- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Run the two overload examples through mypy and trace the existing redundant or unreachable overload diagnostic path, noting how keyword-only parameters are handled. Done means both ordering variants receive an appropriate diagnostic when the later overload cannot be matched.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- compilers, devtools
- Issue type
- Feature
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 48/100