Git hook scripts

A set of configurable git hooks and checks.

Upon committing code, the pre-commit hook runs configured checks against the files to be committed and rejects the commit if any of the checks turned on fail.

Install using pip::

pip install captainhook

Once installed into your environment, you will be able to run::

captainhook

from within any git repo, and the pre-commit hook will be installed.

To turn a check on or off, create a tox.ini file in the base directory of your project with a captainhook section.

eg::

[captainhook]
flake8=off
pdb=off
python3=on

flake8, pdb and python3 checks default to being on.

Checks can also be passed arguments from the config file. This is done with the following notation::

<check_name>=<status>;<string to be passed through>

Currently checks can only be passed a single argument and must do the parsing of that themselves.

flake8 obeys the configuration as per the flake8 docs but any path-related options will need to use wildcard patterns (e.g. exclude=*/migrations/* instead of exclude=migrations).

Currently supported checks are

• pdb: Checks to see if there are any uncommented import pdb; pdb.set_trace() statements in the code to be committed.

• flake8: Runs flake8 against the files that are set to be committed.

• python3: Checks to see if python files set to be committed are python3 compatible.

• grep: Runs the given grep command against the files in your commit.

  • Takes a single argument; options which will be passed through to grep verbatim.
  • Currently you can only specify a single grep command.

You only see output for checks that fail, otherwise silence.

Example output upon a rejected commit::

===============================================================================
Checking python3
===============================================================================
  File "captainhook/pre_commit.py", line 77
    print 'a'
            ^
SyntaxError: invalid syntax
===============================================================================
Checking flake8
===============================================================================
pre-commit.py:19:1: F401 'importlib' imported but unused
pre-commit.py:128:1: E302 expected 2 blank lines, found 1
setup.py:25:80: E501 line too long (89 > 79 characters)
===============================================================================
Rejecting commit
===============================================================================

You can add your own check to your git env quite easily.

Simply add a module to .git/hooks/checkers with a run() method defined.

The method should return the error string on faillure, or a False like object on success.

For example::

$ cat .git/hooks/checkers/mine.py
def run():
    return "NOT A CHANCE"

This will block all commits if enabled.

A variable DEFAULT can be specified in the module and will be used to determine the check is assumed "on" or "off". This value is only used if tox.ini has not been used to override it.

I'm eager to get some feedback - positive or negative - about this.

Please make yourself at home, create issues if you've got problems with existing behaviour, or suggestions for future improvements or anything else.

You can reach me on twitter @couperalex.

Running pre-commit.py on its own will by default cause a git stash to take place which you probably don't want when testing a new check.

You can run the script without performing such a stash using::

python captainhook/pre_commit.py -n