pre-commit

#!/usr/bin/env bash
set -u
# set -x
set -o pipefail

test -f "${GIT_DIR:-.git}/REBASE_HEAD" && exit 0

if [[ $(uname) = 'Darwin' ]]; then
    # no readlink -f on osx :(
    rl=$(python -c 'import os,sys;print(os.path.realpath(sys.argv[1]))' "$0")
else
    rl=$(readlink -f "$0")
fi

readonly HERE=$(dirname "$rl")


warn() {
    if [[ -t 2 ]]; then
        echo -n -e '\033[1;33mWARN\033[0m ' >&2
    else
        echo -n 'WARN ' >&2
    fi
    echo "$@" >&2
}
error() {
    if [[ -t 2 ]]; then
        echo -n -e '\033[1;31mERROR\033[0m ' >&2
    else
        echo -n 'ERROR ' >&2
    fi
    echo "$@" >&2
    exit 1
}


if git rev-parse --verify HEAD >/dev/null 2>&1
then
    against=HEAD
else
    # Initial commit: diff against an empty tree object
    against=4b825dc642cb6eb9a060e54bf8d69288fbee4904
fi

# builtin trailing spaces and conflits markers check
if ! git diff-index --check --cached $against -- >&2; then
    error "git diff --check failed"
fi

diff=$(git diff -z --cached --diff-filter=ACM $against)

debugger=$(echo "$diff" | grep -E -c '^\+.*\b(debugger|set_trace|pu\.db|breakpoint|import q)\b')
if [[ $debugger -gt 0 ]]; then
    error "debugging keyword found"
fi

status=0
# check with flake8
if [[ -n "$(command -v flake8)" ]]; then
    output="cat"
    if [[ -t 2 ]]; then
        # fd 2 is terminal => colored output
        colout=$(command -v colout)
        if [[ -n "$colout" ]]; then
            output="$colout -T $HERE -t flake8"
        fi
    fi

    echo "$diff" | filterdiff -i '*.py' --clean | flake8 --diff -j1 | $output >&2
    status=$?
else
    warn "flake8 not found"
fi

# check with eslint
if [[ -n "$(command -v eslint)" ]]; then
    echo "$diff" | "$HERE"/eslint-diff.py >&2
    es_status=$?
    if [[ $es_status != 0 ]]; then
        status=$es_status
    fi
else
    warn "eslint not found"
fi

exit $status