Lemming

Lemming is a tool for formatting and linting your code. With Lemming, everyone will use the same formatters and linters, with the same version.

Installation

Use the package manager pip to install Lemming. Need more help?

pip install python-lemming

Requirements

Lemming requires Python 3.7

Usage

1. Create the config

Lemming's config lives in these places:

• in the .lemming.toml file
• in the pyproject.toml file

Please note, that there must be a lemming or tool.lemming key in the config file.

The config looks like this:

fail_fast = false  # OPTIONAL, whether or not immediately quit in case of an error

[[formatters]]
name = "some_example"  # OPTIONAL, used to identify this formatter. Defaults to packages[0]
packages = ["example"]  # REQUIRED, the package(s) to install with pip (might include versions with "==x.y.z")
format_command = "{pyexe} -m example {path}"  # REQUIRED, the command to run to format the code ({pyexe} will be replaced with the python executable, {path} with the path passed to Lemming (usually the current working directory: "."))
check_command = "{pyexe} -m example --check {path}"  # OPTIONAL, the command to run to check the code (stuff will be replaced just like in format_command)
allow_nonzero_on_format = true  # OPTIONAL, if true it is allowed for the format_command to return a non-zero exit status

[[linters]]
name = "other_example"  # OPTIONAL, used to identify this linter. Defaults to packages[0]
packages = ["example"]  # REQUIRED, same as for formatters
command = "{pyexe} -m example {path}"  # REQUIRED, the command to run to lint the code (stuff will be replaced just like in format_command)
run_first = true  # OPTIONAL, if true this linter will be ran BEFORE formatters, and other linters. Defaults to false.

2. Run Lemming

After installing Lemming, run

lemming {format,check} .

If you choose format, the format_commands will be ran, but if you choose check, the check_commands will be ran. Linters will be ran in both cases.

You can also use Lemming as a GitHub workflow, like this.

CLI usage

 Usage: lemming [OPTIONS] COMMAND [ARGS]...

╭─ Options ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ --version             -V                                       Print the version of Lemming and exit.                                                              │
│ --install-completion          [bash|zsh|fish|powershell|pwsh]  Install completion for the specified shell. [default: None]                                         │
│ --show-completion             [bash|zsh|fish|powershell|pwsh]  Show completion for the specified shell, to copy it or customize the installation. [default: None]  │
│ --help                                                         Show this message and exit.                                                                         │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
╭─ Commands ─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ check                        Check the formatting of your code and run linters.                                                                                    │
│ format                       Format your code and run linters.                                                                                                     │
│ pre-commit                   Install a pre-commit git hook which will run Lemming.                                                                                 │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯

Check

 Usage: lemming check [OPTIONS] PATHS...

 Check the formatting of your code and run linters.

╭─ Arguments ─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ *    paths      PATHS...  [default: None] [required]                                                                            │
╰─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
╭─ Options ───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ --quiet-commands,--qc                If passed the output of the formatters and linters will be hidden.                         │
│ --quiet-pip,--qp                     If passed the output of pip will be hidden.                                                │
│ --verbose              -v            When passed the logger's threshold will be decreased by 10 (may be passed multiple times)  │
│ --quiet                -q            When passed the logger's threshold will be increased by 10 (may be passed multiple times)  │
│ --config                       FILE  The config file to use [default: None]                                                     │
│ --only                         TEXT  Only run these formatters/linters (may be passed multiple times) [default: None]           │
│ --help                               Show this message and exit.                                                                │
╰─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯

Format

Usage: lemming format [OPTIONS] PATHS...

 Format your code and run linters.

╭─ Arguments ─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ *    paths      PATHS...  [default: None] [required]                                                                            │
╰─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
╭─ Options ───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ --quiet-commands,--qc                If passed the output of the formatters and linters will be hidden.                         │
│ --quiet-pip,--qp                     If passed the output of pip will be hidden.                                                │
│ --verbose              -v            When passed the logger's threshold will be decreased by 10 (may be passed multiple times)  │
│ --quiet                -q            When passed the logger's threshold will be increased by 10 (may be passed multiple times)  │
│ --config                       FILE  The config file to use. [default: None]                                                    │
│ --only                         TEXT  Only run these formatters/linters (may be passed multiple times) [default: None]           │
│ --help                               Show this message and exit.                                                                │
╰─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯

Pre-commit

 Usage: lemming pre-commit [OPTIONS]

 Install a pre-commit git hook which will run Lemming.

╭─ Options ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ --git-repository          DIRECTORY  The root directory of the git repository to use. Defaults to the current working directory. [default: (dynamic)]      │
│ --verbose         -v                 When passed the logger's threshold will be decreased by 10 (may be passed multiple times)                             │
│ --quiet           -q                 When passed the logger's threshold will be increased by 10 (may be passed multiple times)                             │
│ --help                               Show this message and exit.                                                                                           │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯

Support

Questions should be asked in the Discussions tab.

Feature requests and bug reports should be reported in the Issues tab.

Security vulnerabilities should be reported as described in our Security policy (in the SECURITY.md file).

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to add entries to the changelog.

For more information, please read the contributing guidelines.

Authors and acknowledgments

A list of nice people who helped this project can be found in the CONTRIBUTORS file.

License

GNU GPLv3+