dmypy suggest should not suggest for abstract methods?
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Description
Bug Report
with --no-errors the suggestions from dmypy suggest for abstract methods can lead to type errors
To Reproduce
import abc
class C:
@abc.abstractmethod
def get_key(self): pass
class D(C):
def get_key(self):
return 'key'
Expected Behavior
either no suggestion or () -> str for t.C.get_key
Actual Behavior
$ dmypy run t.py
...
$ dmypy suggest t.D.get_key
() -> str
$ dmypy suggest t.C.get_key
() -> None
applying both of these suggestions results in a type error:
$ mypy t.py
t.py:8: error: Return type "str" of "get_key" incompatible with return type "None" in supertype "C" [override]
Found 1 error in 1 file (checked 1 source file)
Your Environment
- Mypy version used: 1.15.0
- Mypy command-line flags: see above
- Mypy configuration options from
mypy.ini(and other config files): n/a - Python version used: 3.13.1
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the dmypy suggest entry point and reproduce the example using dmypy run t.py, then compare suggestions for t.D.get_key and t.C.get_key. The fix is done when an abstract method does not produce a conflicting None return suggestion, and the example passes mypy without an override error.
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
- Clearly specified
- Newbie friendliness
- 50/100