gulpfile.js

var gulp       = require('gulp');
var Server     = require('karma').Server;
var watch      = require('gulp-watch');
var livereload = require('gulp-livereload');
var notify     = require('gulp-notify');

gulp.task('html', function() {
  gulp.src('app/')
    .pipe(livereload())
    .pipe(notify({ message : 'modified HTML'}));
});

gulp.task('js', function() {
  gulp.src('app/')
    .pipe(livereload())
    .pipe(notify({ message : 'modified JS'}));
});

gulp.task('watch', function () {
  livereload.listen();
  gulp.watch('app/**/*.js', ['js']);
  gulp.watch('app/**/*.html', ['html']);
});

/**
 * Run test once and exit
 */
gulp.task('test', function (done) {
  new Server({
    configFile: __dirname + '/karma.conf.js',
    singleRun: true
  }, done).start();
});

/**
 * Watch for file changes and re-run tests on each change
 */
gulp.task('tdd', function (done) {
  new Server({
    configFile: __dirname + '/karma.conf.js'
  }, done).start();
});

gulp.task('default', ['watch']);