[![Black Logo](https://raw.githubusercontent.com/psf/black/main/docs/_static/logo2-readme.png)](https://black.readthedocs.io/en/stable/)

The Uncompromising Code Formatter

> “Any color you like.” _Black_ is the uncompromising Python code formatter. By using it, you agree to cede control over minutiae of hand-formatting. In return, _Black_ gives you speed, determinism, and freedom from `pycodestyle` nagging about formatting. You will save time and mental energy for more important matters. Blackened code looks the same regardless of the project you're reading. Formatting becomes transparent after a while and you can focus on the content instead. _Black_ makes code review faster by producing the smallest diffs possible. Watch the [PyCon 2019 talk](https://youtu.be/esZLCuWs_2Y) to learn more. --- **[Read the documentation on ReadTheDocs!](https://black.readthedocs.io/en/stable)** --- ## Installation and usage ### Installation _Black_ can be installed by running `pip install black`. It requires Python 3.10+ to run. If you want to format Jupyter Notebooks, install with `pip install "black[jupyter]"`. ### Usage To get started right away with sensible defaults: ```sh black {source_file_or_directory} ``` You can run _Black_ as a package if running it as a script doesn't work: ```sh python -m black {source_file_or_directory} ``` Further information can be found in our docs: - [Usage and Configuration](https://black.readthedocs.io/en/stable/usage_and_configuration/index.html) _Black_ is already [successfully used](https://github.com/psf/black#used-by) by many projects, small and big. _Black_ has a comprehensive test suite, with efficient parallel tests, and our own auto formatting and parallel Continuous Integration runner. Now that we have become stable, you should not expect large formatting changes in the future. Stylistic changes will mostly be responses to bug reports and support for new Python syntax. For more information please refer to [The Black Code Style](https://black.readthedocs.io/en/stable/the_black_code_style/index.html). Also, as a safety measure which slows down processing, _Black_ will check that the reformatted code still produces a valid AST that is effectively equivalent to the original (see the [Pragmatism](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#ast-before-and-after-formatting) section for details). If you're feeling confident, use `--fast`. ## The _Black_ code style _Black_ is a PEP 8 compliant opinionated formatter. _Black_ reformats entire files in place. Style configuration options are deliberately limited and rarely added. It doesn't take previous formatting into account (see [Pragmatism](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#pragmatism) for exceptions). Our documentation covers the current _Black_ code style, but planned changes to it are also documented. They're both worth taking a look at: - [The _Black_ Code Style: Current style](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html) - [The _Black_ Code Style: Future style](https://black.readthedocs.io/en/stable/the_black_code_style/future_style.html) Changes to the _Black_ code style are bound by the Stability Policy: - [The _Black_ Code Style: Stability Policy](https://black.readthedocs.io/en/stable/the_black_code_style/index.html#stability-policy) Please refer to this document before submitting an issue. What seems like a bug might be intended behaviour. ### Pragmatism Early versions of _Black_ used to be absolutist in some respects. They took after its initial author. This was fine at the time as it made the implementation simpler and there were not many users anyway. Not many edge cases were reported. As a mature tool, _Black_ does make some exceptions to rules it otherwise holds. - [The _Black_ code style: Pragmatism](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#pragmatism) Please refer to this document before submitting an issue just like with the document above. What seems like a bug might be intended behaviour. ## Configuration _Black_ is able to read project-specific default values for its command line options from a `pyproject.toml` file. This is especially useful for specifying custom `--include` and `--exclude`/`--force-exclude`/`--extend-exclude` patterns for your project. You can find more details in our documentation: - [The basics: Configuration via a file](https://black.readthedocs.io/en/stable/usage_and_configuration/the_basics.html#configuration-via-a-file) And if you're looking for more general configuration documentation: - [Usage and Configuration](https://black.readthedocs.io/en/stable/usage_and_configuration/index.html) **Pro-tip**: If you're asking yourself "Do I need to configure anything?" the answer is "No". _Black_ is all about sensible defaults. Applying those defaults will have your code in compliance with many other _Black_ formatted projects. ## Used by The following notable open-source projects trust _Black_ with enforcing a consistent code style: pytest, tox, Pyramid, Django, Django Channels, Hypothesis, attrs, SQLAlchemy, Poetry, PyPA applications (Warehouse, Bandersnatch, Pipenv, virtualenv), pandas, Pillow, Twisted, LocalStack, every Datadog Agent Integration, Home Assistant, Zulip, Kedro, OpenOA, FLORIS, ORBIT, WOMBAT, and many more. The following organizations use _Black_: Dropbox, KeepTruckin, Lyft, Mozilla, Quora, Duolingo, QuantumBlack, Tesla, Archer Aviation. Are we missing anyone? Let us know. ## Testimonials **Mike Bayer**, [author of `SQLAlchemy`](https://www.sqlalchemy.org/): > I can't think of any single tool in my entire programming career that has given me a > bigger productivity increase by its introduction. I can now do refactorings in about > 1% of the keystrokes that it would have taken me previously when we had no way for > code to format itself. **Dusty Phillips**, [writer](https://smile.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=dusty+phillips): > _Black_ is opinionated so you don't have to be. **Hynek Schlawack**, [creator of `attrs`](https://www.attrs.org/), core developer of Twisted and CPython: > An auto-formatter that doesn't suck is all I want for Xmas! **Carl Meyer**, [Django](https://www.djangoproject.com/) core developer: > At least the name is good. **Kenneth Reitz**, creator of [`requests`](https://requests.readthedocs.io/en/latest/) and [`pipenv`](https://readthedocs.org/projects/pipenv/): > This vastly improves the formatting of our code. Thanks a ton! ## Show your style Use the badge in your project's README.md: ```md [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black) ``` Using the badge in README.rst: ```rst .. image:: https://img.shields.io/badge/code%20style-black-000000.svg :target: https://github.com/psf/black ``` Looks like this: [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black) ## License MIT ## Contributing Welcome! Happy to see you willing to make the project better. You can get started by reading this: - [Contributing: The basics](https://black.readthedocs.io/en/latest/contributing/the_basics.html) You can also take a look at the rest of the contributing docs or talk with the developers: - [Contributing documentation](https://black.readthedocs.io/en/latest/contributing/index.html) - [Chat on Discord](https://discord.gg/RtVdv86PrH) ## Change log The log has become rather long. It moved to its own file. See [CHANGES](https://black.readthedocs.io/en/latest/change_log.html). ## Authors The author list is quite long nowadays, so it lives in its own file. See [AUTHORS.md](./AUTHORS.md) ## Code of Conduct Everyone participating in the _Black_ project, and in particular in the issue tracker, pull requests, and social media activity, is expected to treat other people with respect and more generally to follow the guidelines articulated in the [Python Community Code of Conduct](https://www.python.org/psf/codeofconduct/). At the same time, humor is encouraged. In fact, basic familiarity with Monty Python's Flying Circus is expected. We are not savages. And if you _really_ need to slap somebody, do it with a fish while dancing. # Change Log ## Version 26.5.1 ### 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) ## Version 26.5.0 ### 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) ## Version 26.3.1 ### 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) ## Version 26.3.0 ### 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 eventloop 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) ## Version 26.1.0 ### 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) ## Version 25.12.0 ### 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) ## Version 25.11.0 ### 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: ` (#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) ## Version 25.9.0 ### 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) ## Version 25.1.0 ### 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](https://peps.python.org/pep-0639/). (#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) ## Version 24.10.0 ### 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) ## Version 24.8.0 ### Stable style - Fix crash when `# fmt: off` is used before a closing parenthesis or bracket. (#4363) ### Packaging - Packaging metadata updated: docs are explicitly linked, the issue tracker is now also linked. This improves the PyPI listing for Black. (#4345) ### Parser - Fix regression where Black failed to parse a multiline f-string containing another multiline string (#4339) - Fix regression where Black failed to parse an escaped single quote inside an f-string (#4401) - Fix bug with Black incorrectly parsing empty lines with a backslash (#4343) - Fix bugs with Black's tokenizer not handling `\{` inside f-strings very well (#4422) - Fix incorrect line numbers in the tokenizer for certain tokens within f-strings (#4423) ### Performance - Improve performance when a large directory is listed in `.gitignore` (#4415) ### _Blackd_ - Fix blackd (and all extras installs) for docker container (#4357) ## Version 24.4.2 This is a bugfix release to fix two regressions in the new f-string parser introduced in 24.4.1. ### Parser - Fix regression where certain complex f-strings failed to parse (#4332) ### Performance - Fix bad performance on certain complex string literals (#4331) ## Version 24.4.1 ### Highlights - Add support for the new Python 3.12 f-string syntax introduced by PEP 701 (#3822) ### Stable style - Fix crash involving indented dummy functions containing newlines (#4318) ### Parser - Add support for type parameter defaults, a new syntactic feature added to Python 3.13 by PEP 696 (#4327) ### Integrations - Github Action now works even when `git archive` is skipped (#4313) ## Version 24.4.0 ### Stable style - Fix unwanted crashes caused by AST equivalency check (#4290) ### Preview style - `if` guards in `case` blocks are now wrapped in parentheses when the line is too long. (#4269) - Stop moving multiline strings to a new line unless inside brackets (#4289) ### Integrations - Add a new option `use_pyproject` to the GitHub Action `psf/black`. This will read the Black version from `pyproject.toml`. (#4294) ## Version 24.3.0 ### Highlights This release is a milestone: it fixes Black's first CVE security vulnerability. If you run Black on untrusted input, or if you habitually put thousands of leading tab characters in your docstrings, you are strongly encouraged to upgrade immediately to fix [CVE-2024-21503](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-21503). This release also fixes a bug in Black's AST safety check that allowed Black to make incorrect changes to certain f-strings that are valid in Python 3.12 and higher. ### Stable style - Don't move comments along with delimiters, which could cause crashes (#4248) - Strengthen AST safety check to catch more unsafe changes to strings. Previous versions of Black would incorrectly format the contents of certain unusual f-strings containing nested strings with the same quote type. Now, Black will crash on such strings until support for the new f-string syntax is implemented. (#4270) - Fix a bug where line-ranges exceeding the last code line would not work as expected (#4273) ### Performance - Fix catastrophic performance on docstrings that contain large numbers of leading tab characters. This fixes [CVE-2024-21503](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-21503). (#4278) ### Documentation - Note what happens when `--check` is used with `--quiet` (#4236) ## Version 24.2.0 ### Stable style - Fixed a bug where comments where mistakenly removed along with redundant parentheses (#4218) ### Preview style - Move the `hug_parens_with_braces_and_square_brackets` feature to the unstable style due to an outstanding crash and proposed formatting tweaks (#4198) - Fixed a bug where base expressions caused inconsistent formatting of \*\* in ternary expression (#4154) - Checking for newline before adding one on docstring that is almost at the line limit (#4185) - Remove redundant parentheses in `case` statement `if` guards (#4214). ### Configuration - Fix issue where _Black_ would ignore input files in the presence of symlinks (#4222) - _Black_ now ignores `pyproject.toml` that is missing a `tool.black` section when discovering project root and configuration. Since _Black_ continues to use version control as an indicator of project root, this is expected to primarily change behavior for users in a monorepo setup (desirably). If you wish to preserve previous behavior, simply add an empty `[tool.black]` to the previously discovered `pyproject.toml` (#4204) ### Output - Black will swallow any `SyntaxWarning`s or `DeprecationWarning`s produced by the `ast` module when performing equivalence checks (#4189) ### Integrations - Add a JSONSchema and provide a validate-pyproject entry-point (#4181) ## Version 24.1.1 Bugfix release to fix a bug that made Black unusable on certain file systems with strict limits on path length. ### Preview style - Consistently add trailing comma on typed parameters (#4164) ### Configuration - Shorten the length of the name of the cache file to fix crashes on file systems that do not support long paths (#4176) ## Version 24.1.0 ### Highlights This release introduces the new 2024 stable style (#4106), stabilizing the following changes: - Add parentheses around `if`-`else` expressions (#2278) - Dummy class and function implementations consisting only of `...` are formatted more compactly (#3796) - If an assignment statement is too long, we now prefer splitting on the right-hand side (#3368) - Hex codes in Unicode escape sequences are now standardized to lowercase (#2916) - Allow empty first lines at the beginning of most blocks (#3967, #4061) - Add parentheses around long type annotations (#3899) - Enforce newline after module docstrings (#3932, #4028) - Fix incorrect magic trailing comma handling in return types (#3916) - Remove blank lines before class docstrings (#3692) - Wrap multiple context managers in parentheses if combined in a single `with` statement (#3489) - Fix bug in line length calculations for power operations (#3942) - Add trailing commas to collection literals even if there's a comment after the last entry (#3393) - When using `--skip-magic-trailing-comma` or `-C`, trailing commas are stripped from subscript expressions with more than 1 element (#3209) - Add extra blank lines in stubs in a few cases (#3564, #3862) - Accept raw strings as docstrings (#3947) - Split long lines in case blocks (#4024) - Stop removing spaces from walrus operators within subscripts (#3823) - Fix incorrect formatting of certain async statements (#3609) - Allow combining `# fmt: skip` with other comments (#3959) There are already a few improvements in the `--preview` style, which are slated for the 2025 stable style. Try them out and [share your feedback](https://github.com/psf/black/issues). In the past, the preview style has included some features that we were not able to stabilize. This year, we're adding a separate `--unstable` style for features with known problems. Now, the `--preview` style only includes features that we actually expect to make it into next year's stable style. ### Stable style Several bug fixes were made in features that are moved to the stable style in this release: - Fix comment handling when parenthesising conditional expressions (#4134) - Fix bug where spaces were not added around parenthesized walruses in subscripts, unlike other binary operators (#4109) - Remove empty lines before docstrings in async functions (#4132) - Address a missing case in the change to allow empty lines at the beginning of all blocks, except immediately before a docstring (#4130) - For stubs, fix logic to enforce empty line after nested classes with bodies (#4141) ### Preview style - Add `--unstable` style, covering preview features that have known problems that would block them from going into the stable style. Also add the `--enable-unstable-feature` flag; for example, use `--enable-unstable-feature hug_parens_with_braces_and_square_brackets` to apply this preview feature throughout 2024, even if a later Black release downgrades the feature to unstable (#4096) - Format module docstrings the same as class and function docstrings (#4095) - Fix crash when using a walrus in a dictionary (#4155) - Fix unnecessary parentheses when wrapping long dicts (#4135) - Stop normalizing spaces before `# fmt: skip` comments (#4146) ### Configuration - Print warning when configuration in `pyproject.toml` contains an invalid key (#4165) - Fix symlink handling, properly ignoring symlinks that point outside of root (#4161) - Fix cache mtime logic that resulted in false positive cache hits (#4128) - Remove the long-deprecated `--experimental-string-processing` flag. This feature can currently be enabled with `--preview --enable-unstable-feature string_processing`. (#4096) ### Integrations - Revert the change to run Black's pre-commit integration only on specific git hooks (#3940) for better compatibility with older versions of pre-commit (#4137) ## Version 23.12.1 ### Packaging - Fixed a bug that included dependencies from the `d` extra by default (#4108) ## Version 23.12.0 ### Highlights It's almost 2024, which means it's time for a new edition of _Black_'s stable style! Together with this release, we'll put out an alpha release 24.1a1 showcasing the draft 2024 stable style, which we'll finalize in the January release. Please try it out and [share your feedback](https://github.com/psf/black/issues/4042). This release (23.12.0) will still produce the 2023 style. Most but not all of the changes in `--preview` mode will be in the 2024 stable style. ### Stable style - Fix bug where `# fmt: off` automatically dedents when used with the `--line-ranges` option, even when it is not within the specified line range. (#4084) - Fix feature detection for parenthesized context managers (#4104) ### Preview style - Prefer more equal signs before a break when splitting chained assignments (#4010) - Standalone form feed characters at the module level are no longer removed (#4021) - Additional cases of immediately nested tuples, lists, and dictionaries are now indented less (#4012) - Allow empty lines at the beginning of all blocks, except immediately before a docstring (#4060) - Fix crash in preview mode when using a short `--line-length` (#4086) - Keep suites consisting of only an ellipsis on their own lines if they are not functions or class definitions (#4066) (#4103) ### Configuration - `--line-ranges` now skips _Black_'s internal stability check in `--safe` mode. This avoids a crash on rare inputs that have many unformatted same-content lines. (#4034) ### Packaging - Upgrade to mypy 1.7.1 (#4049) (#4069) - Faster compiled wheels are now available for CPython 3.12 (#4070) ### Integrations - Enable 3.12 CI (#4035) - Build docker images in parallel (#4054) - Build docker images with 3.12 (#4055) ## Version 23.11.0 ### Highlights - Support formatting ranges of lines with the new `--line-ranges` command-line option (#4020) ### Stable style - Fix crash on formatting bytes strings that look like docstrings (#4003) - Fix crash when whitespace followed a backslash before newline in a docstring (#4008) - Fix standalone comments inside complex blocks crashing Black (#4016) - Fix crash on formatting code like `await (a ** b)` (#3994) - No longer treat leading f-strings as docstrings. This matches Python's behaviour and fixes a crash (#4019) ### Preview style - Multiline dicts and lists that are the sole argument to a function are now indented less (#3964) - Multiline unpacked dicts and lists as the sole argument to a function are now also indented less (#3992) - In f-string debug expressions, quote types that are visible in the final string are now preserved (#4005) - Fix a bug where long `case` blocks were not split into multiple lines. Also enable general trailing comma rules on `case` blocks (#4024) - Keep requiring two empty lines between module-level docstring and first function or class definition (#4028) - Add support for single-line format skip with other comments on the same line (#3959) ### Configuration - Consistently apply force exclusion logic before resolving symlinks (#4015) - Fix a bug in the matching of absolute path names in `--include` (#3976) ### Performance - Fix mypyc builds on arm64 on macOS (#4017) ### Integrations - Black's pre-commit integration will now run only on git hooks appropriate for a code formatter (#3940) ## Version 23.10.1 ### Highlights - Maintenance release to get a fix out for GitHub Action edge case (#3957) ### Preview style - Fix merging implicit multiline strings that have inline comments (#3956) - Allow empty first line after block open before a comment or compound statement (#3967) ### Packaging - Change Dockerfile to hatch + compile black (#3965) ### Integrations - The summary output for GitHub workflows is now suppressible using the `summary` parameter. (#3958) - Fix the action failing when Black check doesn't pass (#3957) ### Documentation - It is known Windows documentation CI is broken https://github.com/psf/black/issues/3968 ## Version 23.10.0 ### Stable style - Fix comments getting removed from inside parenthesized strings (#3909) ### Preview style - Fix long lines with power operators getting split before the line length (#3942) - Long type hints are now wrapped in parentheses and properly indented when split across multiple lines (#3899) - Magic trailing commas are now respected in return types. (#3916) - Requir