dict.update has incorrect variance for one of its overloads
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stubs: false positive
- Dominant language
- Python
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Description
from typing import Dict, Union
d: Dict[Union[str, int], None] = {}
e: Dict[str, None] = {}
# not ok
d.update(e)
# ok
d.update(e.items())
# ok
for key, value in e.items():
d[key] = value
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First steps
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- Open a pull request that references the issue number.
Research direction
Start with the dict.update overloads in the Python stubs and reproduce the supplied example with a static type checker. Compare the rejected d.update(e) call with the accepted items() and assignment forms; done when the overload accepts the intended compatible mapping without weakening the other forms.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- tooling
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100