Repository navigation
mypy doesn't catch inheritance of outer class #18393
Description
Bug Report
Inheriting from an outer class raises NameError at runtime, but mypy doesn't catch this.
To Reproduce
class Foo:
class Bar(Foo):
passExpected Behavior
Actual Behavior
Success: no issues found in 1 source file
Your Environment
- Mypy version used: 1.14.0
- Python version used: 3.13
Activity
ahmedkhan1 commentedon Oct 6, 2026
Fixed in #22125. The semantic analyzer now reports an undefined-name error when a nested class directly inherits from its still-executing enclosing class, matching CPython's runtime NameError. The regression, self-check, lint, mypy-primer, and full CI matrix are green.