githook-autopep8.sh

#!/bin/bash
# original gist was from https://gist.github.com/kblomqvist/bb59e781ce3e0006b644
# Installation:
#   cd my_gitproject
#   wget -O pre-commit.sh http://tinyurl.com/mkovs45
#   ln -s ../../pre-commit.sh .git/hooks/pre-commit
#   chmod +x pre-commit.sh
function have_uncommitted()
{
    lines=$(git diff --name-only | wc -l)

    if [ 0 -ne $lines ]; then
        git stash > /dev/null
        echo 1
    else
        echo 0
    fi
}

commit=0
RETURN=0
OPTIONS="--aggressive --in-place"
PEP=$(which autopep8)
exec < /dev/tty
if [ $? -ne 0 ]; then
    echo "[!] autopep8 not installed. Unable to check source file format policy." >&2
    exit 1
fi

echo "Checking files for coding style" >&2

stashed=$(have_uncommitted)
FILES=$(git diff --name-only HEAD~1 | grep -E "\.(py)$")
ROOTDIR=$(git rev-parse --show-toplevel)
# clear stash when we used him
if [ $stashed -eq 1 ]; then
    git stash pop > /dev/null
fi
for FILE in $FILES; do
    # convert to absolute path
    FILE="$ROOTDIR/$FILE"
    $PEP --aggressive $FILE | cmp -s $FILE -
    if [ $? -ne 0 ]; then
        echo "[!] $FILE does not respect the agreed coding style." >&2
        RETURN=1
        # wait for user input to auto clean file
        echo "Should it be cleaned? [y/n] (All other changes will be stashed)"
        read clean_file
        if [[ $clean_file == "y" ]]; then
            echo "cleaning file $FILE"
            stashed=$(have_uncommitted)
            $PEP $OPTIONS $FILE
            git add -u
            if [ $commit -eq 0 ]; then
                commit=1
                git commit -m "cleanup with autopep8"
            else
                #there is already a commit with cleanup so use the same one
                git commit --amend
            fi
            ## replay changes
            # pop all changes which were staged before
            if [ $stashed -eq 1 ]; then
                git stash pop > /dev/null
            fi
            RETURN=0
        fi
    fi
done

if [ $RETURN -eq 1 ]; then
    echo "" >&2
    echo "Make sure you have run pep with the following options:" >&2
    echo "autopep8 $OPTIONS" >&2
fi

exit $RETURN

Git post-commit hook for checking files with autopep8
only files commited are getting checked.