What's New in astroid 4.1.2?

Release date: 2026-03-22

• Fix crash accessing property fset in generic classes with type annotations.
  Closes #2996

• Fix infinite recursion caused by cyclic inference in Constraint.

• Fix RecursionError in _compute_mro() when circular class hierarchies
  are created through runtime name rebinding. Circular bases are now resolved
  to the original class instead of recursing.

  Closes #2967
  Closes pylint-dev/pylint#10821

• Fix DuplicateBasesError crash in dataclass transform when a class has
  duplicate bases in its MRO (e.g., Protocol appearing both directly and
  indirectly). Catch MroError at .mro() call sites in
  brain_dataclasses.py, consistent with the existing pattern elsewhere.

  Closes #2628

• Fix FunctionModel returning descriptor attributes for builtin functions.

  Closes #2743

• Catch MemoryError when inferring f-strings with extremely large format
  widths (e.g. f'{0:11111111111}') so that inference yields Uninferable
  instead of crashing.

  Closes #2762

• Fix ValueError in __str__/repr and error messages when nodes have
  extreme values (very long identifiers or large integers). Clamp pprint width
  to a minimum of 1 and truncate oversized values in error messages.

  Closes #2764