VCS Hooks
=========

Mercurial hook
--------------

To use the Mercurial hook on any *commit* or *qrefresh*, change your .hg/hgrc
file like this::

    [hooks]
    commit = python:flake8.hooks.hg_hook
    qrefresh = python:flake8.hooks.hg_hook

    [flake8]
    strict = 0
    complexity = 12


If *strict* option is set to **1**, any warning will block the commit. When
*strict* is set to **0**, warnings are just printed to the standard output.

*complexity* defines the maximum McCabe complexity allowed before a warning
is emitted.  If you don't specify it, it's just ignored.  If specified, it must
be a positive value.  12 is usually a good value.


Git hook
--------

To use the Git hook on any *commit*, add a **pre-commit** file in the
*.git/hooks* directory containing::

    #!/usr/bin/env python
    import sys
    from flake8.hooks import git_hook

    COMPLEXITY = 10
    STRICT = False

    if __name__ == '__main__':
        sys.exit(git_hook(complexity=COMPLEXITY, strict=STRICT, ignore='E501'))
        # Alternatively
        # sys.exit(git_hook(complexity=COMPLEXITY, strict=STRICT,
        #                   ignore=['E501']))


If *strict* option is set to **True**, any warning will block the commit. When
*strict* is set to **False** or omitted, warnings are just printed to the
standard output.

*complexity* defines the maximum McCabe complexity allowed before a warning
is emitted.  If you don't specify it or set it to **-1**, it's just ignored.
If specified, it must be a positive value.  12 is usually a good value.

*lazy* when set to ``True`` will also take into account files not added to the
index.

Also, make sure the file is executable and adapt the shebang line so it
points to your Python interpreter.

VCS Hooks
=========

flake8 can install hooks for Mercurial and Git so that flake8 is run
automatically before commits. The commit will fail if there are any
flake8 issues.

You can install the hook by issuing this command in the root of your
project::

  $ flake8 --install-hooks

In the case of Git, the hook won't be installed if a custom
``pre-commit`` hook file is already present in
the ``.git/hooks`` directory.

You can control the behavior of the pre-commit hook using environment
variables:

``FLAKE8_COMPLEXITY``
  Any value > 0 enables complexity checking with McCabe. (defaults
  to 10)

``FLAKE8_STRICT``
  If True, this causes the commit to fail in case of any errors at
  all. (defaults to False)

``FLAKE8_IGNORE``
  Comma-separated list of errors and warnings to ignore.  (defaults to
  empty)

``FLAKE8_LAZY``
  If True, also scans those files not added to the index before
  commit. (defaults to False)

Update this to document --install-hooks instead of distracting red herring of the old way to do this.
Update this to document --install-hooks instead of distracting red herring
of the old way to do this.
