"You may need an appropriate loader for this file type", webpack can't parse angular2 file

Question

I'm trying to get a very simple Angular2 app working, with Webpack as a module bundler. I'm following this code, and I copied all the configuration files as they are, only changing file paths. However, when I run npm-start, I get the following error, which I think is a Webpack error:

ERROR in ./hello.js
Module parse failed: /home/marieficid/Documentos/cloud/cloud/hello.js Line 1: Unexpected token
You may need an appropriate loader to handle this file type.
| import {bootstrap} from "angular2/platform/browser";
| import {Component} from "angular2/core";
| 
 @ ./app.ts 2:0-21

As a result, the Angular2 code in my app isn't loaded.

This is my app.ts:

import "./hello.js"; 

This is hello.js, where the error seems to be (which I take to mean that webpack parsed app.ts just fine):

import {bootstrap} from "angular2/platform/browser";
import {Component} from "angular2/core";

@Component({
    selector: 'app',
    template: '<div>Hello world</div>'
})
class App{}

bootstrap(App);

And this iswebpack.config.js:

var webpack = require('webpack');
var HtmlWebpackPlugin = require('html-webpack-plugin');
var path = require('path');

module.exports = {
  entry: {
    'app': './app.ts',
    'vendor': './vendor.ts'
  },
  output: {
    path: "./dist",
    filename: "bundle.js"
  },
  plugins: [
    new webpack.optimize.CommonsChunkPlugin('vendor', 'vendor.bundle.js'),
    new HtmlWebpackPlugin({
      inject: false,
      template: './index.html'
    })       
  ],

  resolve: {
    extensions: ['', '.ts', '.js']
  },

  module: {
    loaders: [
      { test: /\.ts$/, loader: 'ts-loader' },
    ],
    noParse: [ path.join(__dirname, 'node_modules', 'angular2', 'bundles') ]
  },

  devServer: {
    historyApiFallback: true
  }
};

All these files and node_modules are in the same directory.

I have found similar questions online but nothing worked for me. I also didn't install babel because the sample code I'm using as base doesn't use it, but if it's necessary I'm will.

Solution 1

As suggested by @napstablook

Since in your webpack.config.js file you have

resolve: {
   extensions: ['', '.ts', '.js']
},

Webpack will try to handle those .js files but it needs a specific loader to do so which is, if I'm not wrong, script-loader.

In your case the solution is as simple as deleting the .js files, or changing their extension to be .ts.

Solution 2

For me this issue occurred when I ran ng test, please check below points,

• Console will list out the files that is causing the error.
• Check the html file is correctly mapped from the typescript.
• styleUrls file should point to the CSS file not html, this is the mistake I did.