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docs/vcs.rst

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+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.run.hg_hook
+    qrefresh = python:flake8.run.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/python
+    import sys
+    from flake8.run import git_hook
+
+    COMPLEXITY = 10
+    STRICT = False
+
+    if __name__ == '__main__':
+        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.