Configuring Ruff
Ruff can be configured through a pyproject.toml, ruff.toml, or .ruff.toml file.
Whether you're using Ruff as a linter, formatter, or both, the underlying configuration strategy and semantics are the same.
For a complete enumeration of the available configuration options, see Settings.
If left unspecified, Ruff's default configuration is equivalent to:
[tool.ruff]
# Exclude a variety of commonly ignored directories.
exclude = [
".bzr",
".direnv",
".eggs",
".git",
".git-rewrite",
".hg",
".ipynb_checkpoints",
".mypy_cache",
".nox",
".pants.d",
".pyenv",
".pytest_cache",
".pytype",
".ruff_cache",
".svn",
".tox",
".venv",
".vscode",
"__pypackages__",
"_build",
"buck-out",
"build",
"dist",
"node_modules",
"site-packages",
"venv",
]
# Same as Black.
line-length = 88
indent-width = 4
# Assume Python 3.9
target-version = "py39"
[tool.ruff.lint]
# Enable Pyflakes (`F`) and a subset of the pycodestyle (`E`) codes by default.
# Unlike Flake8, Ruff doesn't enable pycodestyle warnings (`W`) or
# McCabe complexity (`C901`) by default.
select = ["E4", "E7", "E9", "F"]
ignore = []
# Allow fix for all enabled rules (when `--fix`) is provided.
fixable = ["ALL"]
unfixable = []
# Allow unused variables when underscore-prefixed.
dummy-variable-rgx = "^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$"
[tool.ruff.format]
# Like Black, use double quotes for strings.
quote-style = "double"
# Like Black, indent with spaces, rather than tabs.
indent-style = "space"
# Like Black, respect magic trailing commas.
skip-magic-trailing-comma = false
# Like Black, automatically detect the appropriate line ending.
line-ending = "auto"
# Enable auto-formatting of code examples in docstrings. Markdown,
# reStructuredText code/literal blocks and doctests are all supported.
#
# This is currently disabled by default, but it is planned for this
# to be opt-out in the future.
docstring-code-format = false
# Set the line length limit used when formatting code snippets in
# docstrings.
#
# This only has an effect when the `docstring-code-format` setting is
# enabled.
docstring-code-line-length = "dynamic"
# Exclude a variety of commonly ignored directories.
exclude = [
".bzr",
".direnv",
".eggs",
".git",
".git-rewrite",
".hg",
".ipynb_checkpoints",
".mypy_cache",
".nox",
".pants.d",
".pyenv",
".pytest_cache",
".pytype",
".ruff_cache",
".svn",
".tox",
".venv",
".vscode",
"__pypackages__",
"_build",
"buck-out",
"build",
"dist",
"node_modules",
"site-packages",
"venv",
]
# Same as Black.
line-length = 88
indent-width = 4
# Assume Python 3.9
target-version = "py39"
[lint]
# Enable Pyflakes (`F`) and a subset of the pycodestyle (`E`) codes by default.
# Unlike Flake8, Ruff doesn't enable pycodestyle warnings (`W`) or
# McCabe complexity (`C901`) by default.
select = ["E4", "E7", "E9", "F"]
ignore = []
# Allow fix for all enabled rules (when `--fix`) is provided.
fixable = ["ALL"]
unfixable = []
# Allow unused variables when underscore-prefixed.
dummy-variable-rgx = "^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$"
[format]
# Like Black, use double quotes for strings.
quote-style = "double"
# Like Black, indent with spaces, rather than tabs.
indent-style = "space"
# Like Black, respect magic trailing commas.
skip-magic-trailing-comma = false
# Like Black, automatically detect the appropriate line ending.
line-ending = "auto"
# Enable auto-formatting of code examples in docstrings. Markdown,
# reStructuredText code/literal blocks and doctests are all supported.
#
# This is currently disabled by default, but it is planned for this
# to be opt-out in the future.
docstring-code-format = false
# Set the line length limit used when formatting code snippets in
# docstrings.
#
# This only has an effect when the `docstring-code-format` setting is
# enabled.
docstring-code-line-length = "dynamic"
As an example, the following would configure Ruff to:
[tool.ruff.lint]
# 1. Enable flake8-bugbear (`B`) rules, in addition to the defaults.
select = ["E4", "E7", "E9", "F", "B"]
# 2. Avoid enforcing line-length violations (`E501`)
ignore = ["E501"]
# 3. Avoid trying to fix flake8-bugbear (`B`) violations.
unfixable = ["B"]
# 4. Ignore `E402` (import violations) in all `__init__.py` files, and in selected subdirectories.
[tool.ruff.lint.per-file-ignores]
"__init__.py" = ["E402"]
"**/{tests,docs,tools}/*" = ["E402"]
[tool.ruff.format]
# 5. Use single quotes in `ruff format`.
quote-style = "single"
[lint]
# 1. Enable flake8-bugbear (`B`) rules, in addition to the defaults.
select = ["E4", "E7", "E9", "F", "B"]
# 2. Avoid enforcing line-length violations (`E501`)
ignore = ["E501"]
# 3. Avoid trying to fix flake8-bugbear (`B`) violations.
unfixable = ["B"]
# 4. Ignore `E402` (import violations) in all `__init__.py` files, and in selected subdirectories.
[lint.per-file-ignores]
"__init__.py" = ["E402"]
"**/{tests,docs,tools}/*" = ["E402"]
[format]
# 5. Use single quotes in `ruff format`.
quote-style = "single"
Linter plugin configurations are expressed as subsections, e.g.:
Ruff respects pyproject.toml, ruff.toml, and .ruff.toml files. All three implement an
equivalent schema (though in the ruff.toml and .ruff.toml versions, the [tool.ruff] header and
tool.ruff section prefix is omitted).
For a complete enumeration of the available configuration options, see Settings.
Config file discovery
Similar to ESLint,
Ruff supports hierarchical configuration, such that the "closest" config file in the
directory hierarchy is used for every individual file, with all paths in the config file
(e.g., exclude globs, src paths) being resolved relative to the directory containing that
config file.
There are a few exceptions to these rules:
- In locating the "closest"
pyproject.tomlfile for a given path, Ruff ignores anypyproject.tomlfiles that lack a[tool.ruff]section. - If a configuration file is passed directly via
--config, those settings are used for all analyzed files, and any relative paths in that configuration file (likeexcludeglobs orsrcpaths) are resolved relative to the current working directory. - If no config file is found in the filesystem hierarchy, Ruff will fall back to using
a default configuration. If a user-specific configuration file exists
at
${config_dir}/ruff/pyproject.toml, that file will be used instead of the default configuration, with${config_dir}being determined viaetcetera's native strategy, and all relative paths being again resolved relative to the current working directory. - Any config-file-supported settings that are provided on the command-line (e.g., via
--select) will override the settings in every resolved configuration file.
Unlike ESLint,
Ruff does not merge settings across configuration files; instead, the "closest" configuration file
is used, and any parent configuration files are ignored. In lieu of this implicit cascade, Ruff
supports an extend field, which allows you to inherit the settings from another
config file, like so:
All of the above rules apply equivalently to pyproject.toml, ruff.toml, and .ruff.toml files.
If Ruff detects multiple configuration files in the same directory, the .ruff.toml file will take
precedence over the ruff.toml file, and the ruff.toml file will take precedence over
the pyproject.toml file.
Python file discovery
When passed a path on the command-line, Ruff will automatically discover all Python files in that
path, taking into account the exclude and extend-exclude
settings in each directory's configuration file.
Files can also be selectively excluded from linting or formatting by scoping the exclude setting
to the tool-specific configuration tables. For example, the following would prevent ruff from
formatting .pyi files, but would continue to include them in linting:
By default, Ruff will also skip any files that are omitted via .ignore, .gitignore,
.git/info/exclude, and global gitignore files (see: respect-gitignore).
Files that are passed to ruff directly are always analyzed, regardless of the above criteria.
For example, ruff check /path/to/excluded/file.py will always lint file.py.
Default inclusions
By default, Ruff will discover files matching *.py, *.pyi, *.ipynb, or pyproject.toml.
To lint or format files with additional file extensions, use the extend-include setting.
You can also change the default selection using the include setting.
Warning
Paths provided to include must match files. For example, include = ["src"] will fail since it
matches a directory.
Jupyter Notebook discovery
Ruff has built-in support for linting and formatting Jupyter Notebooks,
which are linted and formatted by default on version 0.6.0 and higher.
If you'd prefer to either only lint or only format Jupyter Notebook files, you can use the
section-specific exclude option to do so. For example, the following would only lint Jupyter
Notebook files and not format them:
And, conversely, the following would only format Jupyter Notebook files and not lint them:
You can completely disable Jupyter Notebook support by updating the
extend-exclude setting:
If you'd like to ignore certain rules specifically for Jupyter Notebook files, you can do so by
using the per-file-ignores setting:
Some rules have different behavior when applied to Jupyter Notebook files. For
example, when applied to .py files the
module-import-not-at-top-of-file (E402)
rule detect imports at the top of a file, but for notebooks it detects imports at the top of a
cell. For a given rule, the rule's documentation will always specify if it has different
behavior when applied to Jupyter Notebook files.
Command-line interface
Some configuration options can be provided or overridden via dedicated flags on the command line. This includes those related to rule enablement and disablement, file discovery, logging level, and more:
All other configuration options can be set via the command line
using the --config flag, detailed below.
The --config CLI flag
The --config flag has two uses. It is most often used to point to the
configuration file that you would like Ruff to use, for example:
However, the --config flag can also be used to provide arbitrary
overrides of configuration settings using TOML <KEY> = <VALUE> pairs.
This is mostly useful in situations where you wish to override a configuration setting
that does not have a dedicated command-line flag.
In the below example, the --config flag is the only way of overriding the
dummy-variable-rgx configuration setting from the command line,
since this setting has no dedicated CLI flag. The per-file-ignores setting
could also have been overridden via the --per-file-ignores dedicated flag,
but using --config to override the setting is also fine:
$ ruff check path/to/file --config path/to/ruff.toml --config "lint.dummy-variable-rgx = '__.*'" --config "lint.per-file-ignores = {'some_file.py' = ['F841']}"
Configuration options passed to --config are parsed in the same way
as configuration options in a ruff.toml file.
As such, options specific to the Ruff linter need to be prefixed with lint.
(--config "lint.dummy-variable-rgx = '__.*'" rather than simply
--config "dummy-variable-rgx = '__.*'"), and options specific to the Ruff formatter
need to be prefixed with format..
If a specific configuration option is simultaneously overridden by
a dedicated flag and by the --config flag, the dedicated flag
takes priority. In this example, the maximum permitted line length
will be set to 90, not 100:
Specifying --config "line-length=90" will override the line-length
setting from all configuration files detected by Ruff,
including configuration files discovered in subdirectories.
In this respect, specifying --config "line-length=90" has
the same effect as specifying --line-length=90,
which will similarly override the line-length setting from
all configuration files detected by Ruff, regardless of where
a specific configuration file is located.
Full command-line interface
See ruff help for the full list of Ruff's top-level commands:
Ruff: An extremely fast Python linter and code formatter.
Usage: ruff [OPTIONS] <COMMAND>
Commands:
check Run Ruff on the given files or directories
rule Explain a rule (or all rules)
config List or describe the available configuration options
linter List all supported upstream linters
clean Clear any caches in the current directory and any subdirectories
format Run the Ruff formatter on the given files or directories
server Run the language server
analyze Run analysis over Python source code
version Display Ruff's version
help Print this message or the help of the given subcommand(s)
Options:
-h, --help Print help
-V, --version Print version
Log levels:
-v, --verbose Enable verbose logging
-q, --quiet Print diagnostics, but nothing else
-s, --silent Disable all logging (but still exit with status code "1" upon
detecting diagnostics)
Global options:
--config <CONFIG_OPTION>
Either a path to a TOML configuration file (`pyproject.toml` or
`ruff.toml`), or a TOML `<KEY> = <VALUE>` pair (such as you might
find in a `ruff.toml` configuration file) overriding a specific
configuration option. Overrides of individual settings using this
option always take precedence over all configuration files, including
configuration files that were also specified using `--config`
--isolated
Ignore all configuration files
For help with a specific command, see: `ruff help <command>`.
Or ruff help check for more on the linting command:
Run Ruff on the given files or directories
Usage: ruff check [OPTIONS] [FILES]...
Arguments:
[FILES]... List of files or directories to check [default: .]
Options:
--fix
Apply fixes to resolve lint violations. Use `--no-fix` to disable or
`--unsafe-fixes` to include unsafe fixes
--unsafe-fixes
Include fixes that may not retain the original intent of the code.
Use `--no-unsafe-fixes` to disable
--show-fixes
Show an enumeration of all fixed lint violations. Use
`--no-show-fixes` to disable
--diff
Avoid writing any fixed files back; instead, output a diff for each
changed file to stdout, and exit 0 if there are no diffs. Implies
`--fix-only`
-w, --watch
Run in watch mode by re-running whenever files change
--fix-only
Apply fixes to resolve lint violations, but don't report on, or exit
non-zero for, leftover violations. Implies `--fix`. Use
`--no-fix-only` to disable or `--unsafe-fixes` to include unsafe
fixes
--ignore-noqa
Ignore any `# noqa` comments
--output-format <OUTPUT_FORMAT>
Output serialization format for violations. The default serialization
format is "full" [env: RUFF_OUTPUT_FORMAT=] [possible values:
concise, full, json, json-lines, junit, grouped, github, gitlab,
pylint, rdjson, azure, sarif]
-o, --output-file <OUTPUT_FILE>
Specify file to write the linter output to (default: stdout) [env:
RUFF_OUTPUT_FILE=]
--target-version <TARGET_VERSION>
The minimum Python version that should be supported [possible values:
py37, py38, py39, py310, py311, py312, py313]
--preview
Enable preview mode; checks will include unstable rules and fixes.
Use `--no-preview` to disable
--extension <EXTENSION>
List of mappings from file extension to language (one of `python`,
`ipynb`, `pyi`). For example, to treat `.ipy` files as IPython
notebooks, use `--extension ipy:ipynb`
--statistics
Show counts for every rule with at least one violation
--add-noqa
Enable automatic additions of `noqa` directives to failing lines
--show-files
See the files Ruff will be run against with the current settings
--show-settings
See the settings Ruff will use to lint a given Python file
-h, --help
Print help
Rule selection:
--select <RULE_CODE>
Comma-separated list of rule codes to enable (or ALL, to enable all
rules)
--ignore <RULE_CODE>
Comma-separated list of rule codes to disable
--extend-select <RULE_CODE>
Like --select, but adds additional rule codes on top of those already
specified
--per-file-ignores <PER_FILE_IGNORES>
List of mappings from file pattern to code to exclude
--extend-per-file-ignores <EXTEND_PER_FILE_IGNORES>
Like `--per-file-ignores`, but adds additional ignores on top of
those already specified
--fixable <RULE_CODE>
List of rule codes to treat as eligible for fix. Only applicable when
fix itself is enabled (e.g., via `--fix`)
--unfixable <RULE_CODE>
List of rule codes to treat as ineligible for fix. Only applicable
when fix itself is enabled (e.g., via `--fix`)
--extend-fixable <RULE_CODE>
Like --fixable, but adds additional rule codes on top of those
already specified
File selection:
--exclude <FILE_PATTERN>
List of paths, used to omit files and/or directories from analysis
--extend-exclude <FILE_PATTERN>
Like --exclude, but adds additional files and directories on top of
those already excluded
--respect-gitignore
Respect file exclusions via `.gitignore` and other standard ignore
files. Use `--no-respect-gitignore` to disable
--force-exclude
Enforce exclusions, even for paths passed to Ruff directly on the
command-line. Use `--no-force-exclude` to disable
Miscellaneous:
-n, --no-cache
Disable cache reads [env: RUFF_NO_CACHE=]
--cache-dir <CACHE_DIR>
Path to the cache directory [env: RUFF_CACHE_DIR=]
--stdin-filename <STDIN_FILENAME>
The name of the file when passing it through stdin
-e, --exit-zero
Exit with status code "0", even upon detecting lint violations
--exit-non-zero-on-fix
Exit with a non-zero status code if any files were modified via fix,
even if no lint violations remain
Log levels:
-v, --verbose Enable verbose logging
-q, --quiet Print diagnostics, but nothing else
-s, --silent Disable all logging (but still exit with status code "1" upon
detecting diagnostics)
Global options:
--config <CONFIG_OPTION>
Either a path to a TOML configuration file (`pyproject.toml` or
`ruff.toml`), or a TOML `<KEY> = <VALUE>` pair (such as you might
find in a `ruff.toml` configuration file) overriding a specific
configuration option. Overrides of individual settings using this
option always take precedence over all configuration files, including
configuration files that were also specified using `--config`
--isolated
Ignore all configuration files
Or ruff help format for more on the formatting command:
Run the Ruff formatter on the given files or directories
Usage: ruff format [OPTIONS] [FILES]...
Arguments:
[FILES]... List of files or directories to format [default: .]
Options:
--check
Avoid writing any formatted files back; instead, exit with a non-zero
status code if any files would have been modified, and zero otherwise
--diff
Avoid writing any formatted files back; instead, exit with a non-zero
status code and the difference between the current file and how the
formatted file would look like
--extension <EXTENSION>
List of mappings from file extension to language (one of `python`,
`ipynb`, `pyi`). For example, to treat `.ipy` files as IPython
notebooks, use `--extension ipy:ipynb`
--target-version <TARGET_VERSION>
The minimum Python version that should be supported [possible values:
py37, py38, py39, py310, py311, py312, py313]
--preview
Enable preview mode; enables unstable formatting. Use `--no-preview`
to disable
-h, --help
Print help (see more with '--help')
Miscellaneous:
-n, --no-cache
Disable cache reads [env: RUFF_NO_CACHE=]
--cache-dir <CACHE_DIR>
Path to the cache directory [env: RUFF_CACHE_DIR=]
--stdin-filename <STDIN_FILENAME>
The name of the file when passing it through stdin
File selection:
--respect-gitignore
Respect file exclusions via `.gitignore` and other standard ignore
files. Use `--no-respect-gitignore` to disable
--exclude <FILE_PATTERN>
List of paths, used to omit files and/or directories from analysis
--force-exclude
Enforce exclusions, even for paths passed to Ruff directly on the
command-line. Use `--no-force-exclude` to disable
Format configuration:
--line-length <LINE_LENGTH> Set the line-length
Editor options:
--range <RANGE> When specified, Ruff will try to only format the code in
the given range.
It might be necessary to extend the start backwards or
the end forwards, to fully enclose a logical line.
The `<RANGE>` uses the format
`<start_line>:<start_column>-<end_line>:<end_column>`.
Log levels:
-v, --verbose Enable verbose logging
-q, --quiet Print diagnostics, but nothing else
-s, --silent Disable all logging (but still exit with status code "1" upon
detecting diagnostics)
Global options:
--config <CONFIG_OPTION>
Either a path to a TOML configuration file (`pyproject.toml` or
`ruff.toml`), or a TOML `<KEY> = <VALUE>` pair (such as you might
find in a `ruff.toml` configuration file) overriding a specific
configuration option. Overrides of individual settings using this
option always take precedence over all configuration files, including
configuration files that were also specified using `--config`
--isolated
Ignore all configuration files
Shell autocompletion
Ruff supports autocompletion for most shells. A shell-specific completion script can be generated
by ruff generate-shell-completion <SHELL>, where <SHELL> is one of bash, elvish, fig, fish,
powershell, or zsh.
The exact steps required to enable autocompletion will vary by shell. For example instructions, see the Poetry or ripgrep documentation.
As an example: to enable autocompletion for Zsh, run
ruff generate-shell-completion zsh > ~/.zfunc/_ruff. Then add the following line to your
~/.zshrc file, if they're not already present: