⬆️ Update dependency black to v26

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
black (changelog)	25.1.0 → 26.1.0

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Release Notes

psf/black (black)

v26.1.0

Compare Source

Highlights

Introduces the 2026 stable style (#​4892), stabilizing the following changes:

• always_one_newline_after_import: Always force one blank line after import
  statements, except when the line after the import is a comment or an import statement
  (#​4489)
• fix_fmt_skip_in_one_liners: Fix # fmt: skip behavior on one-liner declarations,
  such as def foo(): return "mock" # fmt: skip, where previously the declaration would
  have been incorrectly collapsed (#​4800)
• fix_module_docstring_detection: Fix module docstrings being treated as normal
  strings if preceded by comments (#​4764)
• fix_type_expansion_split: Fix type expansions split in generic functions (#​4777)
• multiline_string_handling: Make expressions involving multiline strings more compact
  (#​1879)
• normalize_cr_newlines: Add \r style newlines to the potential newlines to
  normalize file newlines both from and to (#​4710)
• remove_parens_around_except_types: Remove parentheses around multiple exception
  types in except and except* without as (#​4720)
• remove_parens_from_assignment_lhs: Remove unnecessary parentheses from the left-hand
  side of assignments while preserving magic trailing commas and intentional multiline
  formatting (#​4865)
• standardize_type_comments: Format type comments which have zero or more spaces
  between # and type: or between type: and value to # type: (value) (#​4645)

The following change was not in any previous stable release:

• Regenerated the _width_table.py and added tests for the Khmer language (#​4253)

This release alo bumps pathspec to v1 and fixes inconsistencies with Git's
.gitignore logic (#​4958). Now, files will be ignored if a pattern matches them, even
if the parent directory is directly unignored. For example, Black would previously
format exclude/not_this/foo.py with this .gitignore:

exclude/
!exclude/not_this/

Now, exclude/not_this/foo.py will remain ignored. To ensure exclude/not_this/ and
all of it's children are included in formatting (and in Git), use this .gitignore:

*/exclude/*
!*/exclude/not_this/

This new behavior matches Git. The leading */ are only necessary if you wish to ignore
matching subdirectories (like the previous behavior did), and not just matching root
directories.

Output

• Explicitly shutdown the multiprocessing manager when run in diff mode too (#​4952)

Integrations

• Upgraded PyPI upload workflow to use Trusted Publishing (#​4611)

v25.12.0

Compare Source

Highlights

• Black no longer supports running with Python 3.9 (#​4842)

Stable style

• Fix bug where comments preceding # fmt: off/# fmt: on blocks were incorrectly
  removed, particularly affecting Jupytext's # %% [markdown] comments (#​4845)
• Fix crash when multiple # fmt: skip comments are used in a multi-part if-clause, on
  string literals, or on dictionary entries with long lines (#​4872)
• Fix possible crash when fmt: directives aren't on the top level (#​4856)

Preview style

• Fix fmt: skip skipping the line after instead of the line it's on (#​4855)
• Remove unnecessary parentheses from the left-hand side of assignments while preserving
  magic trailing commas and intentional multiline formatting (#​4865)
• Fix fix_fmt_skip_in_one_liners crashing on with statements (#​4853)
• Fix fix_fmt_skip_in_one_liners crashing on annotated parameters (#​4854)
• Fix new lines being added after imports with # fmt: skip on them (#​4894)

Packaging

• Releases now include arm64 Windows binaries and wheels (#​4814)

Integrations

• Add output-file input to GitHub Action psf/black to write formatter output to a
  file for artifact capture and log cleanliness (#​4824)

v25.11.0

Compare Source

Highlights

• Enable base 3.14 support (#​4804)
• Add support for the new Python 3.14 t-string syntax introduced by PEP 750 (#​4805)

Stable style

• Fix bug where comments between # fmt: off and # fmt: on were reformatted (#​4811)
• Comments containing fmt directives now preserve their exact formatting instead of
  being normalized (#​4811)

Preview style

• Move multiline_string_handling from --unstable to --preview (#​4760)
• Fix bug where module docstrings would be treated as normal strings if preceded by
  comments (#​4764)
• Fix bug where python 3.12 generics syntax split line happens weirdly (#​4777)
• Standardize type comments to form # type: <value> (#​4645)
• Fix fix_fmt_skip_in_one_liners preview feature to respect # fmt: skip for compound
  statements with semicolon-separated bodies (#​4800)

Configuration

• Add no_cache option to control caching behavior. (#​4803)

Packaging

• Releases now include arm64 Linux binaries (#​4773)

Output

• Write unchanged content to stdout when excluding formatting from stdin using pipes
  (#​4610)

Blackd

• Implemented BlackDClient. This simple python client allows to easily send formatting
  requests to blackd (#​4774)

Integrations

• Enable 3.14 base CI (#​4804)
• Enhance GitHub Action psf/black to support the required-version major-version-only
  "stability" format when using pyproject.toml (#​4770)
• Improve error message for vim plugin users. It now handles independently vim version
• Vim: Warn on unsupported Vim and Python versions independently (#​4772)
• Vim: Print the import paths when importing black fails (#​4675)
• Vim: Fix handling of virtualenvs that have a different Python version (#​4675)

v25.9.0

Compare Source

Highlights

• Remove support for pre-python 3.7 await/async as soft keywords/variable names
  (#​4676)

Stable style

• Fix crash while formatting a long del statement containing tuples (#​4628)
• Fix crash while formatting expressions using the walrus operator in complex with
  statements (#​4630)
• Handle # fmt: skip followed by a comment at the end of file (#​4635)
• Fix crash when a tuple appears in the as clause of a with statement (#​4634)
• Fix crash when tuple is used as a context manager inside a with statement (#​4646)
• Fix crash when formatting a \ followed by a \r followed by a comment (#​4663)
• Fix crash on a \\r\n (#​4673)
• Fix crash on await ... (where ... is a literal Ellipsis) (#​4676)
• Fix crash on parenthesized expression inside a type parameter bound (#​4684)
• Fix crash when using line ranges excluding indented single line decorated items
  (#​4670)

Preview style

• Fix a bug where one-liner functions/conditionals marked with # fmt: skip would still
  be formatted (#​4552)
• Improve multiline_string_handling with ternaries and dictionaries (#​4657)
• Fix a bug where string_processing would not split f-strings directly after
  expressions (#​4680)
• Wrap the in clause of comprehensions across lines if necessary (#​4699)
• Remove parentheses around multiple exception types in except and except* without
  as. (#​4720)
• Add \r style newlines to the potential newlines to normalize file newlines both from
  and to (#​4710)

Parser

• Rewrite tokenizer to improve performance and compliance (#​4536)
• Fix bug where certain unusual expressions (e.g., lambdas) were not accepted in type
  parameter bounds and defaults. (#​4602)

Performance

• Avoid using an extra process when running with only one worker (#​4734)

Integrations

• Fix the version check in the vim file to reject Python 3.8 (#​4567)
• Enhance GitHub Action psf/black to read Black version from an additional section in
  pyproject.toml: [project.dependency-groups] (#​4606)
• Build gallery docker image with python3-slim and reduce image size (#​4686)

Documentation

• Add FAQ entry for windows emoji not displaying (#​4714)

---

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⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

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The artifact failure details are included below:

File name: poetry.lock

Updating dependencies
Resolving dependencies...

Creating virtualenv pure-protobuf-9DAEHxhI-py3.14 in /home/ubuntu/.cache/pypoetry/virtualenvs

The current project's supported Python range (>=3.9.0,<4.0.0) is not compatible with some of the required packages Python requirement:
  - black requires Python >=3.10, so it will not be installable for Python >=3.9.0,<3.10

Because pure-protobuf depends on black (26.1.0) which requires Python >=3.10, version solving failed.

  * Check your dependencies Python requirement: The Python requirement can be specified via the `python` or `markers` properties

    For black, a possible solution would be to set the `python` property to ">=3.10,<4.0.0"

    https://python-poetry.org/docs/dependency-specification/#python-restricted-dependencies,
    https://python-poetry.org/docs/dependency-specification/#using-environment-markers