v26.5.1

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Stable style

• Fix unstable formatting of annotated assignments whose subscript annotation contains
  an inline comment (e.g. x: list[ # pyright: ignore[...]) (#​5130)
• Preserve inline comments (including # type: ignore) immediately before a
  # fmt: skip line, avoiding AST equivalence failures (#​5139)

Packaging

• Correct the version in the published executables (#​5137)

Documentation

• Add Neovim integration guide covering conform.nvim, ALE, and simple command approaches
  (#​5124)

v26.5.0

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Highlights

• Add support for unpacking in comprehensions (PEP 798) and for lazy imports (PEP 810),
  both new syntactic features in Python 3.15 (#​5048)
• Python 3.15 is now supported. Compiled wheels are not yet provided for Python 3.15, so
  performance may be slower than on existing Python versions. Wheels will be provided
  once Python 3.15 is later in its release cycle. (#​5127)

Stable style

• Fix # fmt: skip being ignored in nested if expressions with parenthesized in
  clauses (#​4903)
• Add syntactic support for Python 3.15 (#​5048)
• Fix crash when an f-string follows a # fmt: off comment inside brackets (#​5097)
• Preserve multiline compound statement headers when # fmt: skip is placed on the
  colon line (#​5117)

Preview style

• Improve heuristics around whether blank lines should appear before, within and after
  groups of same-name decorated functions (such as @overload groups) in .pyi stub
  files (#​5021)
• Fix blank lines being removed between a function and a decorated class in .pyi stub
  files (#​5092)
• Prevent string merger from creating unsplittable long lines when a pragma comment
  (e.g. # type: ignore) follows the closing bracket (#​5096)

Packaging

• Run CI on 3.15 (#​5127)

Output

• Improve parse error readability by showing multi-line output with an error pointer.
  (#​5068)
• Add SourceASTParseError to distinguish source parse failures from internal safety
  errors, improving error reporting when Black's lenient parser accepts input that
  ast.parse() rejects (#​5080)

Blackd

• Return HTTP 400 (Bad Request) for source parse failures instead of HTTP 500, keeping
  HTTP 500 only for genuine internal safety errors (#​5080)

Integrations

• Added documentation for doctest formatting tools and updated the integrations index to
  match (#​4916)

Documentation

• Use "Version X.Y.Z" headings in changelog for stable permalink anchors on ReadTheDocs
  (#​5063)
• Note in the editor integrations that the SublimeText sublack plugin is archived and
  unmaintained (#​5082)

v26.3.1

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Stable style

• Prevent Jupyter notebook magic masking collisions from corrupting cells by using
  exact-length placeholders for short magics and aborting if a placeholder can no longer
  be unmasked safely (#​5038)

Configuration

• Always hash cache filename components derived from --python-cell-magics so custom
  magic names cannot affect cache paths (#​5038)

Blackd

• Disable browser-originated requests by default, add configurable origin allowlisting
  and request body limits, and bound executor submissions to improve backpressure
  (#​5039)

v26.3.0

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Stable style

• Don't double-decode input, causing non-UTF-8 files to be corrupted (#​4964)
• Fix crash on standalone comment in lambda default arguments (#​4993)
• Preserve parentheses when # type: ignore comments would be merged with other
  comments on the same line, preventing AST equivalence failures (#​4888)

Preview style

• Fix bug where if guards in case blocks were incorrectly split when the pattern had
  a trailing comma (#​4884)
• Fix string_processing crashing on unassigned long string literals with trailing
  commas (one-item tuples) (#​4929)
• Simplify implementation of the power operator "hugging" logic (#​4918)

Packaging

• Fix shutdown errors in PyInstaller builds on macOS by disabling multiprocessing in
  frozen environments (#​4930)

Performance

• Introduce winloop for windows as an alternative to uvloop (#​4996)
• Remove deprecated function uvloop.install() in favor of uvloop.new_event_loop()
  (#​4996)
• Rename maybe_install_uvloop function to maybe_use_uvloop to simplify loop
  installation and creation of either a uvloop/winloop evenloop or default eventloop
  (#​4996)

Output

• Emit a clear warning when the target Python version is newer than the running Python
  version, since AST safety checks cannot parse newer syntax. Also replace the
  misleading "INTERNAL ERROR" message with an actionable error explaining the version
  mismatch (#​4983)

Blackd

• Introduce winloop to be used when windows in use which enables blackd to run faster on
  windows when winloop is installed. (#​4996)

Integrations

• Remove unused gallery script (#​5030)
• Harden parsing of black requirements in the GitHub Action when use_pyproject is
  enabled so that only version specifiers are accepted and direct references such as
  black @​ https://... are rejected. Users should upgrade to the latest version of the
  action as soon as possible. This update is received automatically when using
  psf/black@stable, and is independent of the version of Black installed by the
  action. (#​5031)

Documentation

• Expand preview style documentation with detailed examples for wrap_comprehension_in,
  simplify_power_operator_hugging, and wrap_long_dict_values_in_parens features
  (#​4987)
• Add detailed documentation for formatting Jupyter Notebooks (#​5009)