gulpfile.babel.js

import path from 'path';
import gulp from 'gulp';
import eslint from 'gulp-eslint';
import excludeGitignore from 'gulp-exclude-gitignore';
import mocha from 'gulp-mocha';
import istanbul from 'gulp-istanbul';
import nsp from 'gulp-nsp';
import plumber from 'gulp-plumber';
import babel from 'gulp-babel';
import del from 'del';
import {Instrumenter} from 'isparta';

// Initialize the babel transpiler so ES2015 files gets compiled
// when they're loaded
import 'babel-core/register';

gulp.task('static', () => {
  return gulp.src(['lib/**/*.js', 'test/**/*.js'])
    .pipe(excludeGitignore())
    .pipe(eslint())
    .pipe(eslint.format())
    .pipe(eslint.failAfterError());
});

gulp.task('nsp', (cb) => {
  nsp({package: path.resolve('package.json')}, cb);
});

gulp.task('pre-test', () => {
  return gulp.src(['lib/**/*.js'])
    .pipe(excludeGitignore())
    .pipe(istanbul({
      includeUntested: true,
      instrumenter: Instrumenter
    }))
    .pipe(istanbul.hookRequire());
});

gulp.task('test', ["pre-test"], (cb) => {
  var mochaErr;

  gulp.src(['test/**/*.js'])
    .pipe(plumber())
    .pipe(mocha({reporter: 'spec'}))
    .on('error', (err) => {
      mochaErr = err;
    })
    .pipe(istanbul.writeReports())
    .on('end', () => {
      cb(mochaErr);
    });
});

gulp.task('watch', () => {
  gulp.watch(['lib/**/*.js', 'test/**'], ['test']);
});

gulp.task('babel', ['clean'], () => {
  return gulp.src('lib/**/*.js')
    .pipe(babel())
    .pipe(gulp.dest('dist'));
});

gulp.task('clean', () => {
  return del('dist');
});

gulp.task('prepublish', ['nsp', 'babel']);
gulp.task('default', ['static', 'test']);