Pre-commit hook for Cyclomatic Complexity check

20-complexity.py

from __future__ import print_function

"""
Pre-commit hook for Cyclomatic Complexity check
Works well with radon==2.2.0
"""

__author__ = 'Ivan Styazhkin <ivan@nesusvet.com>'

import subprocess

GIT_CHANGES_CMD = 'git diff --name-only --cached --diff-filter=ACM'.split()
GIT_HASH_CMD = 'git ls-files --stage'.split()

WARNING_LEVEL = 'C'
RADON_CMD = ('radon cc -s -n %s' % WARNING_LEVEL).split()


def get_lines(stdout_text):
    """Assumes your console uses utf-8"""
    return stdout_text.strip().decode('utf-8').split('\n')


def get_python_changes():
    """Returns python filenames which are staged"""
    python_changes = get_lines(subprocess.check_output(GIT_CHANGES_CMD))
    return [s for s in python_changes if s.endswith('.py')]


def main():
    filename_list = get_python_changes()
    if not filename_list:
        return

    pipe = subprocess.Popen(
        RADON_CMD + filename_list,
        stdout=subprocess.PIPE,
    )
    out, _ = pipe.communicate()
    if not out:
        print('\033[92mCheck radon: OK\033[0m')
        return

    print('\033[91mCheck %d files with radon failed\033[0m' %
        len(filename_list)
    )
    print(out)
    return 1


if __name__ == '__main__':
    exit(main())