no error for `collections.abc.MutableMapping` is not subscriptable
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bug
topic-runtime-semantics
- Dominant language
- Python
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- 20.6k
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Description
from collections.abc import MutableMapping
MutableMapping[int, int]
mypy python-version 3.6 test.py: Success: no issues found in 1 source file
python test.py:
TypeError: 'ABCMeta' object is not subscriptable
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Research direction
Reproduce the example from test.py with mypy configured for Python 3.6, then trace how subscriptions of collections.abc.MutableMapping are analyzed. Done means the shown code no longer receives a clean Success result when the runtime raises the reported TypeError.
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Assessment
- Tech stack
- python
- Domain
- tooling
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 35/100