What's New in Pylint 3.2





Summary -- Release highlights

What's new in Pylint 3.2.2?

Release date: TBA

No significant changes.

What's new in Pylint 3.2.2?

Release date: 2024-05-20

False Positives Fixed

  • Fix multiple false positives for generic class syntax added in Python 3.12 (PEP 695).

    Closes #9406 (#9406)

  • Exclude context manager without cleanup from contextmanager-generator-missing-cleanup checks.

    Closes #9625 (#9625)

What's new in Pylint 3.2.1?

Release date: 2024-05-18

False Positives Fixed

  • Exclude if/else branches containing terminating functions (e.g. sys.exit()) from possibly-used-before-assignment checks.

    Closes #9627 (#9627)

  • Don't emit typevar-name-incorrect-variance warnings for PEP 695 style TypeVars. The variance is inferred automatically by the type checker. Adding _co or _contra suffix can help to reason about TypeVar.

    Refs #9638 (#9638)

  • Fix a false positive for possibly-used-before-assignment when using typing.assert_never() (3.11+) to indicate exhaustiveness.

    Closes #9643 (#9643)

Other Bug Fixes

  • Fix a false negative for --ignore-patterns when the directory to be linted is specified using a dot(.) and all files are ignored instead of only the files whose name begin with a dot.

    Closes #9273 (#9273)

  • Restore "errors / warnings by module" section to report output (with -ry).

    Closes #9145 (#9145)

  • trailing-comma-tuple should now be correctly emitted when it was disabled globally but enabled via local message control, after removal of an over-optimisation.

    Refs #9608. (#9608)

  • Add --prefer-stubs=yes option to opt-in to the astroid 3.2 feature that prefers .pyi stubs over same-named .py files. This has the potential to reduce no-member errors but at the cost of more errors such as not-an-iterable from function bodies appearing as ....

    Defaults to no.

    Closes #9626 Closes #9623 (#9626)

Internal Changes

  • Update astroid version to 3.2.1. This solves some reports of RecursionError and also makes the prefer .pyi stubs feature in astroid 3.2.0 opt-in with the aforementioned --prefer-stubs=y option.

    Refs #9139 (#9139)

What's new in Pylint 3.2.0?

Release date: 2024-05-14

New Features

  • Understand six.PY2 and six.PY3 for conditional imports.

    Closes #3501 (#3501)

  • A new github reporter has been added. This reporter returns the output of pylint in a format that Github can use to automatically annotate code. Use it with pylint --output-format=github on your Github Workflows.

    Closes #9443. (#9443)

New Checks

  • Add check possibly-used-before-assignment when relying on names after an if/else switch when one branch failed to define the name, raise, or return.

    Closes #1727 (#1727)

  • Checks for generators that use contextmanagers that don't handle cleanup properly. Is meant to raise visibility on the case that a generator is not fully exhausted and the contextmanager is not cleaned up properly. A contextmanager must yield a non-constant value and not handle cleanup for GeneratorExit. The using generator must attempt to use the yielded context value with x() as y and not just with x().

    Closes #2832 (#2832)

False Negatives Fixed

  • If and Try nodes are now checked for useless return statements as well.

    Closes #9449. (#9449)

  • Fix false negative for property-with-parameters in the case of parameters which are positional-only, keyword-only, variadic positional or variadic keyword.

    Closes #9584 (#9584)

False Positives Fixed

pylint now understands the @overload decorator return values better.

Closes #4696 (#4696) Refs #9606 (#9606)

Performance Improvements

  • Ignored modules are now not checked at all, instead of being checked and then ignored. This should speed up the analysis of large codebases which have ignored modules.

    Closes #9442 (#9442) (#9442)

  • ImportChecker's logic has been modified to avoid context files when possible. This makes it possible to cache module searches on astroid and reduce execution times.

    Refs #9310. (#9310)

  • An internal check for trailing-comma-tuple being enabled for a file or not is now done once per file instead of once for each token.

    Refs #9608. (#9608)