Ruff can be configured through a pyproject.toml, ruff.toml, or .ruff.toml file.
For a complete enumeration of the available configuration options, see Settings.
pyproject.tomlIf left unspecified, Ruff's default configuration is equivalent to:
[tool.ruff] # Enable the pycodestyle (`E`) and Pyflakes (`F`) rules by default. # Unlike Flake8, Ruff doesn't enable pycodestyle warnings (`W`) or # McCabe complexity (`C901`) by default. select = ["E", "F"] ignore = [] # Allow autofix for all enabled rules (when `--fix`) is provided. fixable = ["ALL"] unfixable = [] # Exclude a variety of commonly ignored directories. exclude = [ ".bzr", ".direnv", ".eggs", ".git", ".git-rewrite", ".hg", ".mypy_cache", ".nox", ".pants.d", ".pytype", ".ruff_cache", ".svn", ".tox", ".venv", "__pypackages__", "_build", "buck-out", "build", "dist", "node_modules", "venv", ] per-file-ignores = {} # Same as Black. line-length = 88 # Allow unused variables when underscore-prefixed. dummy-variable-rgx = "^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$" # Assume Python 3.8 target-version = "py38"
As an example, the following would configure Ruff to:
[tool.ruff] # 1. Enable flake8-bugbear (`B`) rules, in addition to the defaults. select = ["E", "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 `path/to/file.py`. [tool.ruff.per-file-ignores] "__init__.py" = ["E402"] "path/to/file.py" = ["E402"] "**/{tests,docs,tools}/*" = ["E402"]
Plugin configurations should be expressed as subsections, e.g.:
[tool.ruff] # Add "Q" to the list of enabled codes. select = ["E", "F", "Q"] [tool.ruff.flake8-quotes] docstring-quotes = "double"
For a complete enumeration of the available configuration options, see Settings.
Ruff mirrors Flake8's rule code system, in which each rule code consists of a one-to-three letter prefix, followed by three digits (e.g., F401). The prefix indicates that “source” of the rule (e.g., F for Pyflakes, E for pycodestyle, ANN for flake8-annotations). The set of enabled rules is determined by the select and ignore options, which accept either the full code (e.g., F401) or the prefix (e.g., F).
As a special-case, Ruff also supports the ALL code, which enables all rules. Note that some pydocstyle rules conflict (e.g., D203 and D211) as they represent alternative docstring formats. Ruff will automatically disable any conflicting rules when ALL is enabled.
If you're wondering how to configure Ruff, here are some recommended guidelines:
select and ignore over extend-select and extend-ignore, to make your rule set explicit.ALL with discretion. Enabling ALL will implicitly enable new rules whenever you upgrade.select = ["E", "F"]) and add a category at-a-time. For example, you might consider expanding to select = ["E", "F", "B"] to enable the popular flake8-bugbear extension.ruff.tomlAs an alternative to pyproject.toml, Ruff will also respect a ruff.toml (or .ruff.toml) file, which implements an equivalent schema (though in the ruff.toml and .ruff.toml versions, the [tool.ruff] header is omitted).
For example, the pyproject.toml described above would be represented via the following ruff.toml (or .ruff.toml):
# Enable flake8-bugbear (`B`) rules. select = ["E", "F", "B"] # Never enforce `E501` (line length violations). ignore = ["E501"] # Avoid trying to fix flake8-bugbear (`B`) violations. unfixable = ["B"] # Ignore `E402` (import violations) in all `__init__.py` files, and in `path/to/file.py`. [per-file-ignores] "__init__.py" = ["E402"] "path/to/file.py" = ["E402"]
For a complete enumeration of the available configuration options, see Settings.
Some configuration options can be provided via the command-line, such as those related to rule enablement and disablement, file discovery, logging level, and more:
ruff check path/to/code/ --select F401 --select F403 --quiet
See ruff help for more on Ruff's top-level commands:
Ruff: An extremely fast Python linter. Usage: ruff [OPTIONS] <COMMAND> Commands: check Run Ruff on the given files or directories (default) 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 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) 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 (default)
Usage: ruff check [OPTIONS] [FILES]...
Arguments:
[FILES]... List of files or directories to check
Options:
--fix
Attempt to automatically fix lint violations. Use `--no-fix` to disable
--show-source
Show violations with source code. Use `--no-show-source` to disable
--show-fixes
Show an enumeration of all autofixed 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. Implies `--fix-only`
-w, --watch
Run in watch mode by re-running whenever files change
--fix-only
Fix any fixable lint violations, but don't report on leftover violations. Implies `--fix`. Use `--no-fix-only` to disable
--ignore-noqa
Ignore any `# noqa` comments
--output-format <OUTPUT_FORMAT>
Output serialization format for violations [env: RUFF_OUTPUT_FORMAT=] [possible values: text, json, json-lines, junit, grouped, github, gitlab, pylint, azure]
-o, --output-file <OUTPUT_FILE>
Specify file to write the linter output to (default: stdout)
--target-version <TARGET_VERSION>
The minimum Python version that should be supported [possible values: py37, py38, py39, py310, py311, py312]
--preview
Enable preview mode; checks will include unstable rules and fixes. Use `--no-preview` to disable
--config <CONFIG>
Path to the `pyproject.toml` or `ruff.toml` file to use for configuration
--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 autofix. Only applicable when autofix itself is enabled (e.g., via `--fix`)
--unfixable <RULE_CODE>
List of rule codes to treat as ineligible for autofix. Only applicable when autofix 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
--isolated
Ignore all configuration files
--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 autofix, 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)
pyproject.toml discoverySimilar to ESLint, Ruff supports hierarchical configuration, such that the “closest” pyproject.toml file in the directory hierarchy is used for every individual file, with all paths in the pyproject.toml file (e.g., exclude globs, src paths) being resolved relative to the directory containing that pyproject.toml file.
There are a few exceptions to these rules:
pyproject.toml file for a given path, Ruff ignores any pyproject.toml files that lack a [tool.ruff] section.--config, those settings are used for across files. Any relative paths in that configuration file (like exclude globs or src paths) are resolved relative to the current working directory.pyproject.toml 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 via the dirs crate, and all relative paths being again resolved relative to the current working directory.pyproject.toml-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 pyproject.toml file, like so:
# Extend the `pyproject.toml` file in the parent directory. extend = "../pyproject.toml" # But use a different line length. line-length = 100
All of the above rules apply equivalently to 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.
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 pyproject.toml file.
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 linted, regardless of the above criteria. For example, ruff check /path/to/excluded/file.py will always lint file.py.
Ruff has built-in support for linting Jupyter Notebooks.
To opt in to linting Jupyter Notebook (.ipynb) files, add the *.ipynb pattern to your include setting, like so:
[tool.ruff] include = ["*.py", "*.pyi", "**/pyproject.toml", "*.ipynb"]
This will prompt Ruff to discover Jupyter Notebook (.ipynb) files in any specified directories, and lint them accordingly.
Alternatively, pass the notebook file(s) to ruff on the command-line directly. For example, ruff check /path/to/notebook.ipynb will always lint notebook.ipynb.
The set of enabled rules is controlled via the select and ignore settings, along with the extend-select and extend-ignore modifiers.
To resolve the enabled rule set, Ruff may need to reconcile select and ignore from a variety of sources, including the current pyproject.toml, any inherited pyproject.toml files, and the CLI (e.g., --select).
In those scenarios, Ruff uses the “highest-priority” select as the basis for the rule set, and then applies any extend-select, ignore, and extend-ignore adjustments. CLI options are given higher priority than pyproject.toml options, and the current pyproject.toml file is given higher priority than any inherited pyproject.toml files.
For example, given the following pyproject.toml file:
[tool.ruff] select = ["E", "F"] ignore = ["F401"]
Running ruff check --select F401 would result in Ruff enforcing F401, and no other rules.
Running ruff check --extend-select B would result in Ruff enforcing the E, F, and B rules, with the exception of F401.
To omit a lint rule entirely, add it to the “ignore” list via ignore or extend-ignore, either on the command-line or in your pyproject.toml file.
To ignore a violation inline, Ruff uses a noqa system similar to Flake8. To ignore an individual violation, add # noqa: {code} to the end of the line, like so:
# Ignore F841. x = 1 # noqa: F841 # Ignore E741 and F841. i = 1 # noqa: E741, F841 # Ignore _all_ violations. x = 1 # noqa
For multi-line strings (like docstrings), the noqa directive should come at the end of the string (after the closing triple quote), and will apply to the entire string, like so:
"""Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor. """ # noqa: E501
To ignore all violations across an entire file, add # ruff: noqa to any line in the file, like so:
# ruff: noqa
To ignore a specific rule across an entire file, add # ruff: noqa: {code} to any line in the file, like so:
# ruff: noqa: F841
Or see the per-file-ignores configuration setting, which enables the same functionality via a pyproject.toml file.
Note that Ruff will also respect Flake8's # flake8: noqa directive, and will treat it as equivalent to # ruff: noqa.
noqa managementRuff supports several workflows to aid in noqa management.
First, Ruff provides a special rule code, RUF100, to enforce that your noqa directives are “valid”, in that the violations they say they ignore are actually being triggered on that line (and thus suppressed). You can run ruff check /path/to/file.py --extend-select RUF100 to flag unused noqa directives.
Second, Ruff can automatically remove unused noqa directives via its autofix functionality. You can run ruff check /path/to/file.py --extend-select RUF100 --fix to automatically remove unused noqa directives.
Third, Ruff can automatically add noqa directives to all failing lines. This is useful when migrating a new codebase to Ruff. You can run ruff check /path/to/file.py --add-noqa to automatically add noqa directives to all failing lines, with the appropriate rule codes.
Ruff respects isort's action comments (# isort: skip_file, # isort: on, # isort: off, # isort: skip, and # isort: split), which enable selectively enabling and disabling import sorting for blocks of code and other inline configuration.
Ruff will also respect variants of these action comments with a # ruff: prefix (e.g., # ruff: isort: skip_file, # ruff: isort: on, and so on). These variants more clearly convey that the action comment is intended for Ruff, but are functionally equivalent to the isort variants.
See the isort documentation for more.
By default, Ruff exits with the following status codes:
0 if no violations were found, or if all present violations were fixed automatically.1 if violations were found.2 if Ruff terminates abnormally due to invalid configuration, invalid CLI options, or an internal error.This convention mirrors that of tools like ESLint, Prettier, and RuboCop.
Ruff supports two command-line flags that alter its exit code behavior:
--exit-zero will cause Ruff to exit with a status code of 0 even if violations were found. Note that Ruff will still exit with a status code of 2 if it terminates abnormally.--exit-non-zero-on-fix will cause Ruff to exit with a status code of 1 if violations were found, even if all such violations were fixed automatically. Note that the use of --exit-non-zero-on-fix can result in a non-zero exit code even if no violations remain after autofixing.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:
fpath+=~/.zfunc autoload -Uz compinit && compinit