#!/usr/bin/env bash

SOURCE_COMMIT="$1"

if [ "$#" -gt 0 ]; then

shift

fi

# If no source commit is given target the default branch

if [ "x$SOURCE_COMMIT" = "x" ]; then

# If remote is not set use the remote of the current branch or fallback to "origin"

if [ "x$REMOTE" = "x" ]; then

BRANCH="$(git rev-parse --abbrev-ref HEAD)"

REMOTE="$(git config --local --get "branch.$BRANCH.remote" || echo 'origin')"

fi

SOURCE_COMMIT="remotes/$REMOTE/HEAD"

fi

# Force colored diff output

DIFF_COLOR_SAVED="$(git config --local --get color.diff)"

if [ "x$DIFF_COLOR_SAVED" != "x" ]; then

git config --local --replace-all "color.diff" "always"

else

git config --local --add "color.diff" "always"

fi

scratch="$(mktemp -t check-format.XXXXXXXXXX)"

finish () {

# Remove temporary file

rm -rf "$scratch"

# Restore setting

if [ "x$DIFF_COLOR_SAVED" != "x" ]; then

git config --local --replace-all "color.diff" "$DIFF_COLOR_SAVED"

else

git config --local --unset "color.diff"

fi

}

# The trap will be invoked whenever the script exits, even due to a signal, this is a bash only

# feature

trap finish EXIT

GIT_CLANG_FORMAT="${GIT_CLANG_FORMAT:-git-clang-format}"

"$GIT_CLANG_FORMAT" --style=file --diff "$@" "$SOURCE_COMMIT" > "$scratch"

# Check for no-ops

grep '^no modified files to format$\|^clang-format did not modify any files$' \

"$scratch" > /dev/null && exit 0

# Dump formatting diff and signal failure

printf \

"\033[31m==== FORMATTING VIOLATIONS DETECTED ====\033[0m

run '\033[33m%s --style=file %s %s\033[0m' to apply these formatting changes\n\n" \

"$GIT_CLANG_FORMAT" "$*" "$SOURCE_COMMIT"

cat "$scratch"

exit 1