v3.2.4

What's new in Pylint 3.2.4?

Release date: 2024-06-26

False Positives Fixed

• Prevent emitting possibly-used-before-assignment when relying on names
  only potentially not defined in conditional blocks guarded by functions
  annotated with typing.Never or typing.NoReturn.

  Closes #9674

Other Bug Fixes

• Fixed a crash when the lineno of a variable used as an annotation wasn't available for undefined-variable.

  Closes #8866

• Fixed a crash when the start value in an enumerate was non-constant and impossible to infer
  (like inenumerate(apples, start=int(random_apple_index)) for unnecessary-list-index-lookup.

  Closes #9078

• Fixed a crash in symilar when the -d or -i short option were not properly recognized.
  It's still impossible to do -d=1 (you must do -d 1).

  Closes #9343

v3.2.3

False Positives Fixed

• Classes with only an Ellipsis (...) in their body do not trigger 'multiple-statements'
  anymore if they are inlined (in accordance with black's 2024 style).

  Closes #9398

• Fix a false positive for redefined-outer-name when there is a name defined in an exception-handling block which shares the same name as a local variable that has been defined in a function body.

  Closes #9671

• Fix a false positive for use-yield-from when using the return value from the yield atom.

  Closes #9696

v3.2.2

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

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

  Closes #9625

v3.2.1

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

• 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

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

  Closes #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

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

  Closes #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

• 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

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

v3.2.0

What's new in Pylint 3.2.0?

Release date: 2024-05-14

Of note: a github reporter, two new checks (possibly-used-before-assignment and contextmanager-generator-missing-cleanup), performance improvements, and an astroid upgrade providing support for @overload and .pyi stubs.

New Features

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

  Closes #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.

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

• Checks for generators that use contextmanagers that don't handle cleanup properly.
  Is meant to raise visibilty 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

False Negatives Fixed

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

  Closes #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

False Positives Fixed

• pylint now understands the @overload decorator return values better.

  Closes #4696
  Refs #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

• 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.

• 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.

v3.1.1

What's new in Pylint 3.1.1?

Release date: 2024-05-13

False Positives Fixed

• Treat attrs.define and attrs.frozen as dataclass decorators in
  too-few-public-methods check.

  Closes #9345

• Fix a false positive with singledispatchmethod-function when a method is decorated with both functools.singledispatchmethod and staticmethod.

  Closes #9531

• Fix a false positive for consider-using-dict-items when iterating using keys() and then deleting an item using the key as a lookup.

  Closes #9554

v3.1.0

Two new checks--use-yield-from, deprecated-attribute-- and a smattering of bug fixes.

New Features

• Skip consider-using-join check for non-empty separators if an suggest-join-with-non-empty-separator option is set to no.

  Closes #8701

• Discover .pyi files when linting.

  These can be ignored with the ignore-patterns setting.

  Closes #9097

• Check TypeAlias and TypeVar (PEP 695) nodes for invalid-name.

  Refs #9196

• Support for resolving external toml files named pylintrc.toml and .pylintrc.toml.

  Closes #9228

• Check for .clear, .discard, .pop and remove methods being called on a set while it is being iterated over.

  Closes #9334

New Checks

• New message use-yield-from added to the refactoring checker. This message is emitted when yielding from a loop can be replaced by yield from.

  Closes #9229.

• Added a deprecated-attribute message to check deprecated attributes in the stdlib.

  Closes #8855

False Positives Fixed

• Fixed false positive for inherit-non-class for generic Protocols.

  Closes #9106

• Exempt TypedDict from typing_extensions from too-many-ancestor checks.

  Refs #9167

False Negatives Fixed

• Extend broad-exception-raised and broad-exception-caught to except*.

  Closes #8827

• Fix a false-negative for unnecessary if blocks using a different than expected ordering of arguments.

  Closes #8947.

Other Bug Fixes

• Improve the message provided for wrong-import-order check. Instead of the import statement ("import x"), the message now specifies the import that is out of order and which imports should come after it. As reported in the issue, this is particularly helpful if there are multiple imports on a single line that do not follow the PEP8 convention.

  The message will report imports as follows:
  For "import X", it will report "(standard/third party/first party/local) import X"
  For "import X.Y" and "from X import Y", it will report "(standard/third party/first party/local) import X.Y"
  The import category is specified to provide explanation as to why pylint has issued the message and guidence to the developer on how to fix the problem.

  Closes #8808

Other Changes

• Print how many files were checked in verbose mode.

  Closes #8935

• Fix a crash when an enum class which is also decorated with a dataclasses.dataclass decorator is defined.

  Closes #9100

Internal Changes

• Update astroid version to 3.1.0.

  Refs #9457

v3.0.4

False Positives Fixed

• used-before-assignment is no longer emitted when using a name in a loop and
  depending on an earlier name assignment in an except block paired with
  else: continue.

  Closes #6804

• Avoid false positives for no-member involving function
  attributes supplied by decorators.

  Closes #9246

• Fixed false positive nested-min-max for nested lists.

  Closes #9307

• Fix false positive for used-before-assignment in a finally block
  when assignments took place in both the try block and each exception handler.

  Closes #9451

Other Bug Fixes

• Catch incorrect ValueError "generator already executing" for Python 3.12.0 - 3.12.2.
  This is fixed upstream in Python 3.12.3.

  Closes #9138

v3.0.3

What's new in Pylint 3.0.3?

Release date: 2023-12-11

False Positives Fixed

• Fixed false positive for unnecessary-lambda when the call has keyword arguments but not the lambda.

  Closes #9148

• Fixed incorrect suggestion for shallow copy in unnecessary-comprehension

  Example of the suggestion:
  #pylint: disable=missing-module-docstring
  a = [1, 2, 3]
  b = [x for x in a]
  b[0] = 0
  print(a) # [1, 2, 3]

  After changing b = [x for x in a] to b = a based on the suggestion, the script now prints [0, 2, 3]. The correct suggestion should be use list(a) to preserve the original behavior.

  Closes #9172

• Fix false positives for undefined-variable and unused-argument for
  classes and functions using Python 3.12 generic type syntax.

  Closes #9193

• Fixed pointless-string-statement false positive for docstrings
  on Python 3.12 type aliases.

  Closes #9268

• Fix false positive for invalid-exception-operation when concatenating tuples
  of exception types.

  Closes #9288

Other Bug Fixes

• Fix a bug where pylint was unable to walk recursively through a directory if the
  directory has an __init__.py file.

  Closes #9210

v3.0.2

False Positives Fixed

• Fix used-before-assignment false positive for generic type syntax (PEP 695, Python 3.12).

  Closes #9110

Other Bug Fixes

• Escape special symbols and newlines in messages.

  Closes #7874

• Fixes suggestion for nested-min-max for expressions with additive operators, list and dict comprehensions.

  Closes #8524

• Fixes ignoring conditional imports with ignore-imports=y.

  Closes #8914

• Emit inconsistent-quotes for f-strings with 3.12 interpreter only if targeting pre-3.12 versions.

  Closes #9113