gulpfile.js

var gulp = require('gulp');
var eslint = require('gulp-eslint');
var mocha = require('gulp-mocha');
var gulpSequence = require('gulp-sequence');
var util = require('gulp-util');

gulp.task('lint', function () {
  // ESLint ignores files with "node_modules" paths.
  // So, it's best to have gulp ignore the directory as well.
  // Also, Be sure to return the stream from the task;
  // Otherwise, the task may end before the stream has finished.
  return gulp.src(['index.js', './src/*.js'])
  // eslint() attaches the lint output to the "eslint" property
  // of the file object so it can be used by other modules.
  .pipe(eslint())
  // eslint.format() outputs the lint results to the console.
  // Alternatively use eslint.formatEach() (see Docs).
  .pipe(eslint.format())
  // To have the process exit with an error code (1) on
  // lint error, return the stream and pipe to failAfterError last.
  .pipe(eslint.failAfterError());
});

gulp.task('test-runner', function() {
  return gulp.src(['test/**/*.js'], { read: false })
    .pipe(mocha({ reporter: 'spec' }))
    .on('error', util.log);
});

gulp.task('test',gulpSequence('lint','test-runner'));


gulp.task('default', ['test'], function () {
// This will only run if the lint task is successful...
});