gulpfile.js

//--------------------------------
//  MODULES
//--------------------------------
var gulp = require('gulp'),
  eslint = require('gulp-eslint'),
  connect = require('gulp-connect'),
  open = require('open'),
  rename = require('gulp-rename'),
  uglify = require('gulp-uglify'),
  header = require('gulp-header'),
  wrap = require('gulp-wrap'),
  concat = require('gulp-concat'),
  ngannotate = require('gulp-ng-annotate'),
  karma = require('gulp-karma'),
  pkg = require('./package.json'),

  //--------------------------------
  //  HELPERS
  //--------------------------------
  karmaConfig = function(action) {
    return {
      frameworks: ['jasmine'],
      browsers: ['PhantomJS'],
      reporters: ['progress'],
      action: action
    };
  },
  TEST_FILES = 'test/**/*.spec.js',
  SRC_FILES = 'src/*.js',
  KARMA_FILES = [
    'demo/vendor/angular.min.js',
    'test/vendor/angular-mocks.js',
    SRC_FILES,
    TEST_FILES
  ],
  PORT = 9999;

//--------------------------------
//  TASKS
//--------------------------------

gulp.task('lint', function() {
  return gulp.src([
      'demo/scripts/directives.js',
      SRC_FILES,
      TEST_FILES
    ])
    .pipe(eslint({
      configFile: '.eslintrc.js'
    }))
    .pipe(eslint.format())
    .pipe(eslint.failOnError());
});

gulp.task('test', function() {
  return gulp.src(KARMA_FILES)
    .pipe(karma(karmaConfig('run')))
    .on('error', function(err) {
      throw err;
    });
});

gulp.task('connect', function() {
  connect.server({
    root: 'demo',
    port: PORT,
    livereload: true
  });
});

gulp.task('server', gulp.series('connect', function() {
  open("http://localhost:" + PORT);
}));

gulp.task('reload', function() {
  return gulp.src('demo/**/*.*')
    .pipe(connect.reload());
});

gulp.task('build', function() {
  return gulp.src(SRC_FILES)
    .pipe(concat('featureFlags.js'))
    .pipe(wrap('(function(){\n<%= contents %>\n}());'))
    .pipe(header([
      '/*!',
      ' * <%= title %> v<%= version %>',
      ' *',
      ' * © <%= new Date().getFullYear() %>, <%= author.name %>',
      ' */\n\n'
    ].join('\n'), pkg))
    .pipe(ngannotate({
      add: true,
      single_quotes: true
    }))
    .pipe(gulp.dest('dist/'))
    .pipe(rename('featureFlags.min.js'))
    .pipe(uglify())
    .pipe(header([
      '/*! <%= title %> v<%= version %> © <%= new Date().getFullYear() %> <%= author.name %> */\n'
    ].join(''), pkg))
    .pipe(gulp.dest('dist/'))
    .pipe(gulp.dest('demo/scripts'));
});

gulp.task('dev', gulp.series('build', 'server', function() {
  gulp.watch(['demo/**/*.*'], ['reload']);
  gulp.watch(['demo/scripts/*.js', TEST_FILES], ['lint']);
  gulp.watch(SRC_FILES, ['lint', 'build']);
  gulp.src(KARMA_FILES)
    .pipe(karma(karmaConfig('watch')));
}));

gulp.task('precommit', gulp.series('lint', 'test', 'build'));
gulp.task('demo', gulp.series('build', 'server'));
gulp.task('default', gulp.parallel('precommit'));