#!/bin/sh

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

FILES=$(git diff-index --name-only --diff-filter=ACMR --cached $against -- |egrep ".py$")
if [ "$FILES" != "" ]; then
    # We want to look at the staged version only, so we have to run it once for
    # each file.
    E=0
    for F in ${FILES}; do
	P=$(git show ":$F" | python3 -c "import sys; compile(sys.stdin.read(), '/dev/null', 'exec')")
	if [ "$?" != "0" ]; then
	    echo "Errors in $F"
	    echo $P
	    E=1
	    continue
	fi

	R=$(git show ":$F" | pycodestyle -)
	if [ "$?" != "0" ]; then
	    echo "Errors in $F"
	    echo "$R"
	    E=1
	fi
    done
    if [ "$E" != "0" ]; then
	exit 1
    fi

    echo Basic python checks passed.
fi