Git pre-commit hook with PHPCS

composer.json

{
  ...
  "scripts": {
    "post-install-cmd": "(cd .git/hooks/; ln -s -f ../../mysite/tools/git-pre-commit-hook ./pre-commit)"
 },

phplint.sh

#!/bin/bash

##
# PHPCS check
# Usage: ./phplint "file1 file2"
##

PHPCS_BIN=vendor/bin/phpcs
PHPCS_IGNORE=
FILES_TO_CHECK=$1

# Simple check if code sniffer is set up correctly
if [ ! -x $PHPCS_BIN ]; then
    echo "PHP CodeSniffer bin not found or executable -> $PHPCS_BIN"
    exit 1
fi

# Execute the code sniffer
if [ "$PHPCS_IGNORE" != "" ]; then
    PHPCS_IGNORE="--ignore=$PHPCS_IGNORE"
else
    PHPCS_IGNORE=""
fi

OUTPUT=$($PHPCS_BIN $PHPCS_IGNORE $FILES_TO_CHECK)
RETVAL=$?

# Delete temporary copy of staging area
rm -rf $TMP_STAGING

if [ $RETVAL -ne 0 ]; then
    echo "$OUTPUT" | less
fi

exit $RETVAL

pre-commit.sh

#!/bin/bash

###
# Make sure to run this script from project root
# Usage: 
#  1. `chmod +x pre-commit.sh`
#  2. Symlink / copy this file to `.git/hooks/pre-commit`
###

TMP_STAGING=".tmp_staging"

# Special hash value in git which denotes an empty tree.
# It does not change from repo to repo.
EMPTY_TREE_HASH=4b825dc642cb6eb9a060e54bf8d69288fbee4904

# Stolen from template file
if git rev-parse --verify HEAD
then
    against=HEAD
else
    # Initial commit: diff against an empty tree object
    against=4b825dc642cb6eb9a060e54bf8d69288fbee4904
fi

# This is the magic:
# Retrieve all files in staging area that are added, modified or renamed
# but no deletions etc
FILES=$(git diff-index --name-only --cached --diff-filter=ACMR $against -- )

if [ "$FILES" == "" ]; then
    exit 0
fi

# Create temporary copy of staging area
if [ -e $TMP_STAGING ]; then
    rm -rf $TMP_STAGING
fi
mkdir $TMP_STAGING

# Match files against whitelist
FILES_TO_CHECK=""
for FILE in $FILES
do
    echo "$FILE" | egrep -q "$PHPCS_FILE_PATTERN"
    RETVAL=$?
    if [ "$RETVAL" -eq "0" ]
    then
        FILES_TO_CHECK="$FILES_TO_CHECK $FILE"
    fi
done

if [ "$FILES_TO_CHECK" == "" ]; then
    exit 0
fi

# Copy contents of staged version of files to temporary staging area
# because we only want the staged version that will be commited and not
# the version in the working directory
STAGED_FILES=""
for FILE in $FILES_TO_CHECK
do
  ID=$(git diff-index --cached $against $FILE | cut -d " " -f4)

  # Create staged version of file in temporary staging area with the same
  # path as the original file so that the phpcs ignore filters can be applied
  mkdir -p "$TMP_STAGING/$(dirname $FILE)"
  git cat-file blob $ID > "$TMP_STAGING/$FILE"
  STAGED_FILES="$STAGED_FILES $TMP_STAGING/$FILE"
done

# PHPCS
path_to_phplint "$STAGED_FILES"
RETVAL=$?

# Other checks can go there...

# Delete temporary copy of staging area
rm -rf $TMP_STAGING

exit $RETVAL