A post-checkout hook script to check Composer package status and warn of changes after switching branches

post-checkout

#!/bin/bash
#
# A post-checkout hook script to check Composer package status 
# and warn of changes after switching branches.
#
# Put this file at: .git/hooks/post-checkout
# and make it executable
# You can install it system wide too, see http://stackoverflow.com/a/2293578/685587

PREV_COMMIT=$1
POST_COMMIT=$2

NO_COLOR='\x1B[0m'
RED_COLOR='\x1B[37;41m'

if [[ -f composer.lock ]]; then
    DIFF=`git diff --shortstat ${PREV_COMMIT}..${POST_COMMIT} composer.lock`
    if [[ ${DIFF} != "" ]]; then
        PACKAGE_COUNT=`composer install --dry-run --no-ansi 2>&1 | egrep "  - (Uninstalling|Installing|Updating)" | wc -l | tr -d ' '`
        if [[ ${PACKAGE_COUNT} != "0" ]]; then
            echo -e "$RED_COLOR*** composer.lock has changed and $PACKAGE_COUNT package(s) are out of sync. You should run composer install. ***$NO_COLOR"
        fi
    fi
fi

Fork includes:

• additional test to check for >0 package changes before issuing warning,
• ANSI codes suitable for Mac OS X, and
• additional comment description.