v25.1.0

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Highlights

This release introduces the new 2025 stable style (#​4558), stabilizing
the following changes:

• Normalize casing of Unicode escape characters in strings to lowercase (#​2916)
• Fix inconsistencies in whether certain strings are detected as docstrings (#​4095)
• Consistently add trailing commas to typed function parameters (#​4164)
• Remove redundant parentheses in if guards for case blocks (#​4214)
• Add parentheses to if clauses in case blocks when the line is too long (#​4269)
• Whitespace before # fmt: skip comments is no longer normalized (#​4146)
• Fix line length computation for certain expressions that involve the power operator (#​4154)
• Check if there is a newline before the terminating quotes of a docstring (#​4185)
• Fix type annotation spacing between * and more complex type variable tuple (#​4440)

The following changes were not in any previous release:

• Remove parentheses around sole list items (#​4312)
• Generic function definitions are now formatted more elegantly: parameters are
  split over multiple lines first instead of type parameter definitions (#​4553)

Stable style

• Fix formatting cells in IPython notebooks with magic methods and starting or trailing
  empty lines (#​4484)
• Fix crash when formatting with statements containing tuple generators/unpacking
  (#​4538)

Preview style

• Fix/remove string merging changing f-string quotes on f-strings with internal quotes
  (#​4498)
• Collapse multiple empty lines after an import into one (#​4489)
• Prevent string_processing and wrap_long_dict_values_in_parens from removing
  parentheses around long dictionary values (#​4377)
• Move wrap_long_dict_values_in_parens from the unstable to preview style (#​4561)

Packaging

• Store license identifier inside the License-Expression metadata field, see
  PEP 639. (#​4479)

Performance

• Speed up the is_fstring_start function in Black's tokenizer (#​4541)

Integrations

• If using stdin with --stdin-filename set to a force excluded path, stdin won't be
  formatted. (#​4539)

v24.10.0

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Highlights

• Black is now officially tested with Python 3.13 and provides Python 3.13
  mypyc-compiled wheels. (#​4436) (#​4449)
• Black will issue an error when used with Python 3.12.5, due to an upstream memory
  safety issue in Python 3.12.5 that can cause Black's AST safety checks to fail. Please
  use Python 3.12.6 or Python 3.12.4 instead. (#​4447)
• Black no longer supports running with Python 3.8 (#​4452)

Stable style

• Fix crashes involving comments in parenthesised return types or X | Y style unions.
  (#​4453)
• Fix skipping Jupyter cells with unknown %% magic (#​4462)

Preview style

• Fix type annotation spacing between * and more complex type variable tuple (i.e. def fn(*args: *tuple[*Ts, T]) -> None: pass) (#​4440)

Caching

• Fix bug where the cache was shared between runs with and without --unstable (#​4466)

Packaging

• Upgrade version of mypyc used to 1.12 beta (#​4450) (#​4449)
• blackd now requires a newer version of aiohttp. (#​4451)

Output

• Added Python target version information on parse error (#​4378)
• Add information about Black version to internal error messages (#​4457)