pre-commit.sh

#!/bin/bash
# vim: et ts=4 sw=4 ft=sh

# Interesting post on max line length:
# http://stackoverflow.com/questions/88942/why-should-python-pep-8-specify-a-maximum-line-length-of-79-characters

PEP8_CMD='pep8'
PEP8_OPTIONS='--max-line-length=120'
ESLINT_CMD='eslint'
SASSLINT_CMD='sass-lint'


RED=$(echo -e $"\033[1;31m")
YELLOW=$(echo -e $"\033[0;33m")
CYAN=$(echo -e $"\033[0;36m")
RESET=$(echo -e $"\033[0;0m")
BRIGHTYELLOW=$(echo -e $"\033[1;33m")
WHITE=$(echo -e $"\033[1;37m")

RE="s/\([^:]*\):\([0-9]*\):\([0-9]*\): \([EW][0-9]*\) \(.*\)/$WHITE[$CYAN\1$RESET $BRIGHTYELLOW\2:\3$WHITE] $RED\4 $YELLOW\5$RESET/g"
STATUS=0

_get_files() {
    local i
    unset FILES
    while IFS= read -r -d $'\0' file; do
        FILES[i++]="$file"
    done < <(git diff --name-only --diff-filter=ACMR --staged -z "$1")
}

# Most spammy checks first so the most likely useful ones are at the
# bottom and thus less likely to scroll out of view immediately

# SASSLint
_get_files '*.scss'
if [[ ${#FILES[@]} -ne 0 ]]; then
    RESULT=$(FORCE_COLOR=1 $SASSLINT_CMD -vq "${FILES[@]}")
    RC=$?
    if [[ $RC != 0 ]] ; then
        STATUS=1
        echo "${RED}There are SCSS errors in your code:${RESET}"
        echo "$RESULT"
    elif [[ -n "$RESULT" ]] ; then
        STATUS=1
        echo "${BRIGHTYELLOW}There are SCSS warnings in your code:${RESET}"
        echo "$RESULT"
    fi
fi


# ESLint
_get_files '*.js'
if [[ ${#FILES[@]} -ne 0 ]]; then
    RESULT=$($ESLINT_CMD --color "${FILES[@]}")
    RC=$?
    if [[ $RC != 0 ]] ; then
        STATUS=1
        echo "${RED}There are JS errors in your code:${RESET}"
        echo "$RESULT"
    elif [[ -n "$RESULT" ]] ; then
        STATUS=1
        echo "${BRIGHTYELLOW}There are JS warnings in your code:${RESET}"
        echo "$RESULT"
    fi
fi


# PEP8
RESULT=$(git diff -U0 --staged | $PEP8_CMD --diff $PEP8_OPTIONS)
RC=$?
if [[ $RC != 0 ]] ; then
    echo "${RED}There are PEP8 issues in your code:${RESET}"
    STATUS=1
fi
if [[ -n "$RESULT" ]] ; then
    echo "$RESULT" | sed -e "$RE"
    echo
fi


if [[ $STATUS != 0 ]] ; then
    # claim stdin back
    exec < /dev/tty
    echo
    read -r -p "${RED}Do you wish to commit it anyway ${CYAN}[${WHITE}y${CYAN}/${WHITE}N${CYAN}]${RESET}? " yn
    case $yn in
        [Yy]* ) exit 0;;
        [Nn]* ) exit $STATUS;;
        * ) exit $STATUS;;
    esac
    # close stdin
    exec <&-
fi

exit $STATUS