v2.17.2

False Positives Fixed

• invalid-name now allows for integers in typealias names:

  • now valid: Good2Name, GoodName2.
  • still invalid: _1BadName.

  Closes #8485

• No longer consider Union as type annotation as type alias for naming
  checks.

  Closes #8487

• unnecessary-lambda no longer warns on lambdas which use its parameters in
  their body (other than the final arguments), e.g.
  lambda foo: (bar if foo else baz)(foo).

  Closes #8496

Other Bug Fixes

• Fix a crash in pyreverse when "/" characters are used in the output filename
  e.g pyreverse -o png -p name/ path/to/project.

  Closes #8504

v3.0.0a6

3.0.0a6 is an alpha release, other breaking changes will be added before the official 3.0.0 release. We're including the new features and false negative fixes that will be in 3.0.0, so it's the latest current version of pylint.

Breaking Changes

• pyreverse now uses a new default color palette that is more colorblind
  friendly.
  The color scheme is taken from Paul Tol's Notes.
  If you prefer other colors, you can use the --color-palette option to
  specify custom colors.

  Closes #8251

• Everything related to the __implements__ construct was removed. It was
  based on PEP245
  that was proposed in 2001 and rejected in 2006.

  The capability from pyreverse to take __implements__ into account when
  generating diagrams
  was also removed.

  Refs #8404

• pyreverse: Support for the .vcg output format (Visualaization of
  Compiler Graphs) has been dropped.

  Closes #8416

• The warning when the now useless old pylint cache directory (pylint.d) was
  found was removed. The cache dir is documented in
  the
  FAQ.

  Refs #8462

Changes requiring user actions

• epylint was removed. It now lives at:
  https://github.com/emacsorphanage/pylint.

  Refs #7737

• The 'overgeneral-exceptions' option now only takes fully qualified name
  into account (builtins.Exception not Exception). If you overrode
  this option, you need to use the fully qualified name now.

  There's still a warning, but it will be removed in 3.1.0.

  Refs #8411

• Following a deprecation period, it's no longer possible to use MASTER
  or master as configuration section in setup.cfg or tox.ini. It's
  bad practice
  to not start sections titles with the tool name. Please use pylint.main
  instead.

  Refs #8465

New Features

• Add new option (--show-stdlib, -L) to pyreverse.
  This is similar to the behavior of --show-builtin in that standard
  library
  modules are now not included by default, and this option will include them.

  Closes #8181

False Positives Fixed

• Adds asyncSetUp to the default defining-attr-methods list to silence
  attribute-defined-outside-init warning when using
  unittest.IsolatedAsyncioTestCase.

  Refs #8403

• invalid-name now allows for integers in typealias names:

  • now valid: Good2Name, GoodName2.
  • still invalid: _1BadName.

  Closes #8485

• No longer consider Union as type annotation as type alias for naming
  checks.

  Closes #8487

• unnecessary-lambda no longer warns on lambdas which use its parameters in
  their body (other than the final arguments), e.g.
  lambda foo: (bar if foo else baz)(foo).

  Closes #8496

Other Bug Fixes

• --clear-cache-post-run now also clears LRU caches for pylint utilities
  holding references to AST nodes.

  Closes #8361

• Fix a crash when TYPE_CHECKING is used without importing it.

  Closes #8434

• Fix a used-before-assignment false positive when imports
  are made under the TYPE_CHECKING else if branch.

  Closes #8437

• Fix a regression of preferred-modules where a partial match was used
  instead of the required full match.

  Closes #8453

Other Changes

• Pylint now exposes its type annotations.

  Closes #5488 and #2079

• All code related to the optparse config parsing has been removed.

  Refs #8405

Internal Changes

• get_message_definition was removed from the base checker API. You can
  access
  message definitions through the MessageStore.

  Refs #8401

• Everything related to the __implements__ construct was removed. It was
  based on PEP245
  that was proposed in 2001 and rejected in 2006.

  All the classes inheriting Interface in pylint.interfaces were
  removed.
  Checker should only inherit BaseChecker or any of the other checker
  types
  from pylint.checkers. Reporter should only inherit BaseReporter.

  Refs #8404

• modname and msg_store are now required to be given in FileState.
  collect_block_lines has also been removed. Pylinter.current_name
  cannot be null anymore.

  Refs #8407

• 'Reporter.set_output' was removed in favor of 'reporter.out = stream'.

  Refs #8408

• A number of old utility functions and classes have been removed:

  MapReduceMixin: To make a checker reduce map data simply implement
  get_map_data and reduce_map_data.

  is_inside_lambda: Use utils.get_node_first_ancestor_of_type(x, nodes.Lambda)

  check_messages: Use utils.only_required_for_messages

  is_class_subscriptable_pep585_with_postponed_evaluation_enabled: Use
  is_postponed_evaluation_enabled(node) and
  is_node_in_type_annotation_context(node)

  get_python_path: assumption that there's always an init.py is not
  true since
  python 3.3 and is causing problems, particularly with PEP 420. Use
  discover_package_path
  and pass source root(s).

  fix_import_path: Use augmented_sys_path and pass additional
  sys.path
  entries as an argument obtained from discover_package_path.

  get_global_option: Use checker.linter.config to get all global
  options.

  Related private objects have been removed as well.

  Refs #8409

• colorize_ansi now only accept a MessageStyle object.

  Refs #8412

• The following utilities are deprecated in favor of the more robust
  in_type_checking_block
  and will be removed in pylint 3.0:

  • is_node_in_guarded_import_block
  • is_node_in_typing_guarded_import_block
  • is_typing_guard

  is_sys_guard is still available, which was part of
  is_node_in_guarded_import_block.

  Refs #8433

• Following a deprecation period, Pylinter.check now only work with
  sequences of strings, not strings.

  Refs #8463

• Following a deprecation period, ColorizedTextReporter only accepts
  ColorMappingDict.

  Refs #8464

• Following a deprecation period, MessageTest's end_line and
  end_col_offset
  must be accurate in functional tests (for python 3.8 or above on cpython, and
  for
  python 3.9 or superior on pypy).

  Refs #8466

• Following a deprecation period, the do_exit argument of the Run class
  (and of the _Run
  class in testutils) were removed.

  Refs #8472

• Following a deprecation period, the py_version argument of the
  MessageDefinition.may_be_emitted function is now required. The most
  likely solution
  is to use 'linter.config.py_version' if you need to keep using this
  function, or to use 'MessageDefinition.is_message_enabled' instead.

  Refs #8473

• Following a deprecation period, the OutputLine class now requires
  the right number of argument all the time. The functional output can be
  regenerated automatically to achieve that easily.

  Refs #8474

• Following a deprecation period, is_typing_guard,
  is_node_in_typing_guarded_import_block and
  is_node_in_guarded_import_block: from pylint.utils were removed: use
  a combination of
  is_sys_guard and in_type_checking_block instead.

  Refs #8475

• Following a deprecation period, the location argument of the
  Message class must now be a MessageLocationTuple.

  Refs #8477

• Following a deprecation period, the check_single_file function of the
  Pylinter is replaced by Pylinter.check_single_file_item.

  Refs #8478

v2.17.1

False Positives Fixed

• Adds asyncSetUp to the default defining-attr-methods list to silence
  attribute-defined-outside-init warning when using
  unittest.IsolatedAsyncioTestCase.

  Refs #8403

Other Bug Fixes

• --clear-cache-post-run now also clears LRU caches for pylint utilities
  holding references to AST nodes.

  Closes #8361

• Fix a crash when TYPE_CHECKING is used without importing it.

  Closes #8434

• Fix a regression of preferred-modules where a partial match was used
  instead of the required full match.

  Closes #8453

Internal Changes

• The following utilities are deprecated in favor of the more robust
  in_type_checking_block
  and will be removed in pylint 3.0:

  • is_node_in_guarded_import_block
  • is_node_in_typing_guarded_import_block
  • is_typing_guard

  is_sys_guard is still available, which was part of
  is_node_in_guarded_import_block.

  Refs #8433

v2.17.0

2.17 is a small release that is the first to support python 3.11 officially
with the addition of TryStar nodes.

There's still two new default checks: bad-chained-comparison and
implicit-flag-alias, one of them already fixed a previously undetected
bug in sentry.

Thanks to the community effort our documentation is almost complete,
and almost all messages should have a proper documentation now.
A big thank you to everyone who participated !

The next release is going to be 3.0.0, bring breaking changes and
enact long announced deprecations. There's going to be frequent beta
releases, before the official releases, everyone is welcome to try the betas
so we find problems before the actual release.

What's new in Pylint 2.17.0?

Release date: 2023-03-08

New Features

• pyreverse now supports custom color palettes with the --color-palette
  option.

  Closes #6738

• Add invalid-name check for TypeAlias names.

  Closes #7081

• Accept values of the form <class name>.<attribute name> for the
  exclude-protected list.

  Closes #7343

• Add --version option to pyreverse.

  Refs #7851

• Adds new functionality with preferred-modules configuration to detect
  submodules.

  Refs #7957

• Support implicit namespace packages (PEP 420).

  Closes #8154

• Add globbing pattern support for --source-roots.

  Closes #8290

• Support globbing pattern when defining which file/directory/module to lint.

  Closes #8310

• pylint now supports TryStar nodes from Python 3.11 and should be fully
  compatible with Python 3.11.

  Closes #8387

New Checks

• Add a bad-chained-comparison check that emits a warning when
  there is a chained comparison where one expression is semantically
  incompatible with the other.

  Closes #6559

• Adds an implicit-flag-alias check that emits a warning when a class
  derived from enum.IntFlag assigns distinct integer values that share
  common bit positions.

  Refs #8102

False Positives Fixed

• Fix various false positives for functions that return directly from
  structural pattern matching cases.

  Closes #5288

• Fix false positive for used-before-assignment when
  typing.TYPE_CHECKING is used with if/elif/else blocks.

  Closes #7574

• Fix false positive for isinstance-second-argument-not-valid-type with union
  types.

  Closes #8205

• Fix false positive for used-before-assignment for named expressions
  appearing after the first element in a list, tuple, or set.

  Closes #8252

• Fix false positive for wrong-spelling-in-comment with class names in a
  python 2 type comment.

  Closes #8370

False Negatives Fixed

• Fix a false negative for 'missing-parentheses-for-call-in-test' when
  inference
  failed for the internal of the call as we did not need that information to
  raise
  correctly.

  Refs #8185

• Fix false negative for inconsistent-returns with while-loops.

  Closes #8280

Other Bug Fixes

• Fix used-before-assignment false positive when the walrus operator
  is used with a ternary operator in dictionary key/value initialization.

  Closes #8125

• Fix no-name-in-module false positive raised when a package defines a
  variable with the
  same name as one of its submodules.

  Closes #8148

• Fix a crash happening for python interpreter < 3.9 following a failed typing
  update.

  Closes #8161

• Fix nested-min-max suggestion message to indicate it's possible to splat
  iterable objects.

  Closes #8168

• Fix a crash happening when a class attribute was negated in the start
  argument of an enumerate.

  Closes #8207

• Prevent emitting invalid-name for the line on which a global
  statement is declared.

  Closes #8307

Other Changes

• Update explanation for global-variable-not-assigned and add confidence.

  Closes #5073

• The governance model and the path to become a maintainer have been documented
  as part of our effort to guarantee that the software supply chain in which pylint is included is secure.

  Refs #8329

v2.16.4

False Positives Fixed

• Fix false positive for isinstance-second-argument-not-valid-type with union
  types.

  Closes #8205

v2.16.3

False Positives Fixed

• Fix false positive for wrong-spelling-in-comment with class names in a
  python 2 type comment.

  Closes #8370

Other Bug Fixes

• Prevent emitting invalid-name for the line on which a global
  statement is declared.

  Closes #8307

v2.16.2

New Features

• Add --version option to pyreverse.

  Refs #7851

False Positives Fixed

• Fix false positive for used-before-assignment when
  typing.TYPE_CHECKING is used with if/elif/else blocks.

  Closes #7574

• Fix false positive for used-before-assignment for named expressions
  appearing after the first element in a list, tuple, or set.

  Closes #8252

Other Bug Fixes

• Fix used-before-assignment false positive when the walrus operator
  is used with a ternary operator in dictionary key/value initialization.

  Closes #8125

• Fix no-name-in-module false positive raised when a package defines a
  variable with the same name as one of its submodules.

  Closes #8148

• Fix nested-min-max suggestion message to indicate it's possible to splat
  iterable objects.

  Closes #8168

• Fix a crash happening when a class attribute was negated in the start
  argument of an enumerate.

  Closes #8207

v2.16.1

Other Bug Fixes

• Fix a crash happening for python interpreter < 3.9 following a failed typing
  update.

  Closes #8161

v2.16.0

Summary -- Release highlights

In 2.16.0 we added aggregation and composition understanding in pyreverse, and a way to clear
the cache in between run in server mode (originally for the VS Code integration). Apart from the bug
fixes there's also a lot of new checks, and new extensions that have been asked for for a long time
that were implemented.

If you want to benefit from all the new checks load the following plugins::

pylint.extensions.dict_init_mutate,
pylint.extensions.dunder,
pylint.extensions.typing,
pylint.extensions.magic_value,

We still welcome any community effort to help review, integrate, and add good/bad examples to the doc for
#5953. This should be doable without any pylint or astroid
knowledge, so this is the perfect entrypoint if you want to contribute to pylint or open source without
any experience with our code!

Last but not least @clavedeluna and @nickdrozd became triagers, welcome to the team !

What's new in Pylint 2.16.0?

Changes requiring user actions

• The accept-no-raise-doc option related to missing-raises-doc will now
  be correctly taken into account all the time.

  Pylint will no longer raise missing-raises-doc (W9006) when no exceptions are
  documented and accept-no-raise-doc is true (issue #7208).
  If you were expecting missing-raises-doc errors to be raised in that case,
  you
  will now have to add accept-no-raise-doc=no in your configuration to keep
  the same behavior.
  Closes #7208

New Features

• Added the no-header output format. If enabled with
  --output-format=no-header, it will not include the module name in the
  output.
  Closes #5362

• Added configuration option clear-cache-post-run to support server-like
  usage.
  Use this flag if you expect the linted files to be altered between runs.
  Refs #5401

• Add --allow-reexport-from-package option to configure the
  useless-import-alias check not to emit a warning if a name
  is reexported from a package.
  Closes #6006

• Update pyreverse to differentiate between aggregations and compositions.
  pyreverse checks if it's an Instance or a Call of an object via method
  parameters (via type hints)
  to decide if it's a composition or an aggregation.
  Refs #6543

New Checks

• Adds a pointless-exception-statement check that emits a warning when an
  Exception is created and not assigned, raised or returned.
  Refs #3110

• Add a shadowed-import message for aliased imports.
  Closes #4836

• Add new check called unbalanced-dict-unpacking to check for unbalanced
  dict unpacking
  in assignment and for loops.
  Closes #5797

• Add new checker positional-only-arguments-expected to check for cases
  when
  positional-only arguments have been passed as keyword arguments.
  Closes #6489

• Added singledispatch-method which informs that @singledispatch should
  decorate functions and not class/instance methods.
  Added singledispatchmethod-function which informs that
  @singledispatchmethod should decorate class/instance methods and not
  functions.
  Closes #6917

• Rename broad-except to broad-exception-caught and add new checker
  broad-exception-raised
  which will warn if general exceptions BaseException or Exception are
  raised.
  Closes #7494

• Added nested-min-max which flags min(1, min(2, 3)) to simplify to
  min(1, 2, 3).
  Closes #7546

• Extended use-dict-literal to also warn about call to dict() when
  passing keyword arguments.
  Closes #7690

• Add named-expr-without-context check to emit a warning if a named
  expression is used outside a context like if, for, while, or
  a comprehension.
  Refs #7760

• Add invalid-slice-step check to warn about a slice step value of 0
  for common builtin sequences.
  Refs #7762

• Add consider-refactoring-into-while-condition check to recommend
  refactoring when
  a while loop is defined with a constant condition with an immediate if
  statement to check for break condition as a first statement.
  Closes #8015

Extensions

• Add new extension checker dict-init-mutate that flags mutating a
  dictionary immediately
  after the dictionary was created.
  Closes #2876

• Added bad-dunder-name extension check, which flags bad or misspelled
  dunder methods.
  You can use the good-dunder-names option to allow specific dunder names.
  Closes #3038

• Added consider-using-augmented-assign check for CodeStyle extension
  which flags x = x + 1 to simplify to x += 1.
  This check is disabled by default. To use it, load the code style extension
  with load-plugins=pylint.extensions.code_style and add
  consider-using-augmented-assign in the enable option.
  Closes #3391

• Add magic-number plugin checker for comparison with constants instead of
  named constants or enums.
  You can use it with --load-plugins=pylint.extensions.magic_value.
  Closes #7281

• Add redundant-typehint-argument message for typing plugin for duplicate
  assign typehints.
  Enable the plugin to enable the message with:
  --load-plugins=pylint.extensions.typing.
  Closes #7636

False Positives Fixed

• Fix false positive for unused-variable and unused-import when a name
  is only used in a string literal type annotation.
  Closes #3299

• Document a known false positive for useless-suppression when disabling
  line-too-long in a module with only comments and no code.
  Closes #3368

• trailing-whitespaces is no longer reported within strings.
  Closes #3822

• Fix false positive for global-variable-not-assigned when a global
  variable is re-assigned via an ImportFrom node.
  Closes #4809

• Fix false positive for use-maxsplit-arg with custom split method.
  Closes #4857

• Fix logging-fstring-interpolation false positive raised when logging and
  f-string with %s formatting.
  Closes #4984

• Fix false-positive for used-before-assignment in pattern matching
  with a guard.
  Closes #5327

• Fix use-sequence-for-iteration when unpacking a set with *.
  Closes #5788

• Fix deprecated-method false positive when alias for method is similar to
  name of deprecated method.
  Closes #5886

• Fix false positive assigning-non-slot when a class attribute is
  re-assigned.
  Closes #6001

• Fix false positive for too-many-function-args when a function call is
  assigned to a class attribute inside the class where the function is defined.
  Closes #6592

• Fixes false positive abstract-method on Protocol classes.
  Closes #7209

• Pylint now understands the kw_only keyword argument for dataclass.
  Closes #7290, closes #6550, closes #5857

• Fix false positive for undefined-loop-variable in for-else loops that
  use a function
  having a return type annotation of NoReturn or Never.
  Closes #7311

• Fix used-before-assignment for functions/classes defined in type checking
  guard.
  Closes #7368

• Fix false positive for unhashable-member when subclassing dict and
  using the subclass as a dictionary key.
  Closes #7501

• Fix the message for unnecessary-dunder-call for __aiter__ and
  __aneext__. Also
  only emit the warning when py-version >= 3.10.
  Closes #7529

• Fix used-before-assignment false positive when else branch calls
  sys.exit or similar terminating functions.
  Closes #7563

• Fix a false positive for used-before-assignment for imports guarded by
  typing.TYPE_CHECKING later used in variable annotations.
  Closes #7609

• Fix a false positive for simplify-boolean-expression when multiple values
  are inferred for a constant.
  Closes #7626

• unnecessary-list-index-lookup will not be wrongly emitted if
  enumerate is called with start.
  Closes #7682

• Don't warn about stop-iteration-return when using next() over
  itertools.cycle.
  Closes #7765

• Fixes used-before-assignment false positive when the walrus operator
  is used in a ternary operator.
  Closes #7779

• Fix missing-param-doc false positive when function parameter has an
  escaped underscore.
  Closes #7827

• Fixes method-cache-max-size-none false positive for methods inheriting
  from Enum.
  Closes #7857

• multiple-statements no longer triggers for function stubs using inlined
  ....
  Closes #7860

• Fix a false positive for used-before-assignment when a name guarded by
  if TYPE_CHECKING: is used as a type annotation in a function body and
  later re-imported in the same scope.
  Closes #7882

• Prevent used-before-assignment when imports guarded by if TYPE_CHECKING
  are guarded again when used.
  Closes #7979

• Fixes false positive for try-except-raise with multiple exceptions in one
  except statement if exception are in different namespace.
  Closes #8051

• Fix invalid-name errors for typing_extension.TypeVar.
  Refs #8089

• Fix no-kwoa false positive for context managers.
  Closes #8100

• Fix a false positive for redefined-variable-type when async methods
  are present.
  Closes #8120

False Negatives Fixed

• Code following a call to quit, exit, sys.exit or os._exit
  will be marked as unreachable.
  Refs #519

• Emit used-before-assignment when function arguments are redefined inside
  an inner function and accessed there before assignment.
  Closes #2374

...

v2.16.0b1

New beta release following a performance fix in the new pointless exception statement checks in #8073 and a false positive fixed in the unreleased consider-using-augmented-assign check in #8088. We're also using the latest version of astroid (2.13.3).

The complete changelog will be published when the actual 2.16.0 is released.