gulpfile.js

'use strict';

var gulp   = require('gulp');
var plugins = require('gulp-load-plugins')();

var testFiles = ['./test/**/*.js', '!test/{temp,fixtures,temp/**,fixtures/**}'];
var paths = {
  lint: ['./gulpfile.js', './src/**/*.js'],
  watch: ['./gulpfile.js', './src/**'].concat(testFiles),
  tests: testFiles,
  source: ['./src/**/*.js', './dist.js']
};

var plumberConf = {};

if (process.env.CI) {
  plumberConf.errorHandler = function(err) {
    throw err;
  };
}

gulp.task('lint', function () {
  return gulp.src(paths.lint)
    .pipe(plugins.jshint('.jshintrc'))
    .pipe(plugins.plumber(plumberConf))
    .pipe(plugins.jscs())
    .pipe(plugins.jshint.reporter('jshint-stylish'));
});

gulp.task('istanbul', function (cb) {
  gulp.src(paths.source)
    .pipe(plugins.istanbul()) // Covering files
    .pipe(plugins.istanbul.hookRequire()) // Force `require` to return covered files
    .on('finish', function () {
      gulp.src(paths.tests)
        .pipe(plugins.plumber(plumberConf))
        .pipe(plugins.mocha())
        .pipe(plugins.istanbul.writeReports()) // Creating the reports after tests runned
        .on('finish', function() {
          process.chdir(__dirname);
          cb();
        });
    });
});

gulp.task('watch', ['test'], function () {
  gulp.watch(paths.watch, function() {
    // use child process, otherwise will get error.
    require('child_process').spawn('gulp', ['test'], {
      env: process.env,
      cwd: process.cwd(),
      stdio: [
        process.stdin,
        process.stdout,
        process.stderr
      ]
    });
  });
});

gulp.task('test', ['lint', 'istanbul']);

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