(🐞) Confusing error message in `.format` call with union
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bug
- Dominant language
- Python
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- 20.6k
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Description
from datetime import date
d: date | None
"{:%d}".format(d) # error: Unrecognized format specification "%d" [str-format]
What this error really means is that None doesn't define a __format__ method.
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Research direction
Reproduce the .format example from the issue and trace the str-format diagnostic for a union containing None. The change is done when the reported error explains that None lacks a __format__ method rather than attributing the problem to the %d format specification.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- devtools
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100