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)