pre-push hook linting changed files and running test + checkstyle

pre-push

#!/usr/bin/env bash
printf "<pre-push>\n";

BRANCH=$(git rev-parse --abbrev-ref HEAD)
if [[ "$BRANCH" = "master" ]]; then
    cd frontend;
    FRONTEND_DIFF=`git diff-index --name-only --relative origin/master`;
    if [ "$FRONTEND_DIFF" ];
    then
        printf "Frontend files changed: \n$FRONTEND_DIFF\n";

        printf "************* ESLINT *************\n"
        node_modules/.bin/eslint $FRONTEND_DIFF;

        printf "************* MOCHA TESTS *************\n"
        node_modules/.bin/mocha "src/{comhem/test/**/*.*,**/*.spec.*}" --reporter progress
    else
        printf 'No frontend changes\n';
    fi;


    cd ..
    JAVA_DIFF=`git diff-index --name-only --relative origin/master | grep .java | sed 's/.*\/java/**/g' | tr '\n' ',' | sed 's/,$//'`
    if [ "$JAVA_DIFF" ];
    then
        printf "Java files changed\n$JAVA_DIFF\n"

        printf "************* CHECKSTYLE *************\n"
        mvn checkstyle:check -f src/pom.xml -Dcheckstyle.includes="$JAVA_DIFF" -q
    else
        printf "No java changes\n";
    fi;
fi;
printf "</pre-push>\n";