ES6 import module with Gulp

Question

I am trying to import my ES6 module into a file and running Gulp to concat and minify the file. I'm running into a ReferenceError: require is not defined at all.js(transpiled) line no 3. I have transpiled the code using gulp-babel.

My js files are:

cart.js:

class Cart{
  constructor(){
    this.cart = [];
    this.items = items = [{
        id: 1,
        name: 'Dove Soap',
        price: 39.99
    },{
        id: 2,
        name: 'Axe Deo',
        price: 99.99
    }];
  }


  getItems(){
    return this.items;
  }


}

export {Cart};

app.js:

import {Cart} from 'cart.js';

let cart = new Cart();

console.log(cart.getItems());

gulpfile.js:

"use strict";

let gulp = require('gulp');
let jshint = require('gulp-jshint');
let concat = require('gulp-concat');
let uglify = require('gulp-uglify');
let rename = require('gulp-rename');
let babel = require('gulp-babel');


// Lint Task
gulp.task('lint', function() {
    return gulp.src('js/*.js')
        .pipe(jshint())
        .pipe(jshint.reporter('default'));
});


// Concatenate & Minify JS
gulp.task('scripts', function() {
    return gulp.src('js/*.js')
        .pipe(babel({
            presets: ['env']
        }))
        .pipe(concat('all.js'))
        .pipe(gulp.dest('dist'))
        .pipe(rename('all.min.js'))
        .pipe(uglify().on('error', function(e){
          console.dir(e);
        }))
        .pipe(gulp.dest('dist/js'));
});

// Default Task
gulp.task('default', ['lint','scripts']);

app.js(transpiled):

'use strict';

var _cart = require('cart.js'); //Uncaught ReferenceError: require is not defined

var cart = new _cart.Cart();

console.log(cart.getItems());
'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var Cart = function () {
  function Cart() {
    _classCallCheck(this, Cart);

    this.cart = [];
    this.items = items = [{
      id: 1,
      name: 'Dove Soap',
      price: 39.99
    }, {
      id: 2,
      name: 'Axe Deo',
      price: 99.99
    }];
  }

  _createClass(Cart, [{
    key: 'getItems',
    value: function getItems() {
      return this.items;
    }
  }]);

  return Cart;
}();

exports.Cart = Cart;

Answer 1

You would need a bundler like Webpack or Browserify in order to use ES6 imports. Babel is only capable of compiling ES6 code to ES5 (native JS).

Both Webpack and Browserify have made recipes for gulp:

• https://webpack.js.org/guides/integrations/#gulp
• https://github.com/gulpjs/gulp/tree/master/docs/recipes

Hope this helps.