npm run build throws error code ELIFECYCLE

Question

I've been following Wes Bos series "ES6 for everyone" for a while now and I got stuck on a webpack episode. Whenever I try to run "npm run build" command on my CMD i get this error:

npm ERR! code ELIFECYCLE npm ERR! errno 1 npm ERR! webpacktest@1.0.0 build: webpack --progress --watch npm ERR! Exit status 1 npm ERR! npm ERR! Failed at the webpacktest@1.0.0 build script. npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

After searching for various solutions on the web I end up here in hope you guys can help me. Here is the log file of the run command:

0 info it worked
if it ends with ok
1 verbose cli['C:\\Program Files\\nodejs\\node.exe',
  1 verbose cli 'C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js',
  1 verbose cli 'run',
  1 verbose cli 'build']
2 info using npm @5 .6 .0
3 info using node @v8 .10 .0
4 verbose run - script['prebuild', 'build', 'postbuild']
5 info lifecycle webpacktest @1 .0 .0~prebuild: webpacktest @1 .0 .0
6 info lifecycle webpacktest @1 .0 .0~build: webpacktest @1 .0 .0
7 verbose lifecycle webpacktest @1 .0 .0~build: unsafe - perm in lifecycle true
8 verbose lifecycle webpacktest @1 .0 .0~build: PATH: C: \Program Files\ nodejs\ node_modules\ npm\ node_modules\ npm - lifecycle\ node - gyp - bin;
C: \Users\ Laurynas\ Desktop\ es6.io - master\ New folder\ webpacktest\ node_modules\.bin;
C: \ProgramData\ Oracle\ Java\ javapath;
C: \Windows\ system32;
C: \Windows;
C: \Windows\ System32\ Wbem;
C: \Windows\ System32\ WindowsPowerShell\ v1 .0\;
C: \Program Files(x86)\ NVIDIA Corporation\ PhysX\ Common;
C: \Program Files(x86)\ GtkSharp\ 2.12\ bin;
C: \Program Files\ nodejs\;
C: \Program Files\ Git\ cmd;
C: \Users\ Laurynas\ AppData\ Roaming\ npm;
C: \Program Files\ Microsoft VS Code\ bin
9 verbose lifecycle webpacktest @1 .0 .0~build: CWD: C: \Users\ Laurynas\ Desktop\ es6.io - master\ New folder\ webpacktest
10 silly lifecycle webpacktest @1 .0 .0~build: Args: ['/d /s /c', 'webpack --progress --watch']
11 silly lifecycle webpacktest @1 .0 .0~build: Returned: code: 1 signal: null
12 info lifecycle webpacktest @1 .0 .0~build: Failed to exec build script
13 verbose stack Error: webpacktest @1 .0 .0 build: `webpack --progress --watch`
13 verbose stack Exit status 1
13 verbose stack at EventEmitter. < anonymous > (C: \Program Files\ nodejs\ node_modules\ npm\ node_modules\ npm - lifecycle\ index.js: 285: 16)
13 verbose stack at emitTwo(events.js: 126: 13)
13 verbose stack at EventEmitter.emit(events.js: 214: 7)
13 verbose stack at ChildProcess. < anonymous > (C: \Program Files\ nodejs\ node_modules\ npm\ node_modules\ npm - lifecycle\ lib\ spawn.js: 55: 14)
13 verbose stack at emitTwo(events.js: 126: 13)
13 verbose stack at ChildProcess.emit(events.js: 214: 7)
13 verbose stack at maybeClose(internal / child_process.js: 925: 16)
13 verbose stack at Process.ChildProcess._handle.onexit(internal / child_process.js: 209: 5)
14 verbose pkgid webpacktest @1 .0 .0
15 verbose cwd C: \Users\ Laurynas\ Desktop\ es6.io - master\ New folder\ webpacktest
16 verbose Windows_NT 10.0 .10586
17 verbose argv "C:\\Program Files\\nodejs\\node.exe"
"C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js"
"run"
"build"
18 verbose node v8 .10 .0
19 verbose npm v5 .6 .0
20 error code ELIFECYCLE
21 error errno 1
22 error webpacktest @1 .0 .0 build: `webpack --progress --watch`
22 error Exit status 1
23 error Failed at the webpacktest @1 .0 .0 build script.
23 error This is probably not a problem with npm.There is likely additional logging output above.
24 verbose exit[1, true]

Answer 1

So after a while I figured out the solution, I just don't know how it worked, but here:

I had to change my package.json file. At first it had content like this (it was shown in the tutorial exactly like this"

const webpack = require('webpack');
const nodeEnv = process.env.NODE_ENV || 'production';

module.exports = {
  devtool: 'source-map',
  entry: {
    filename: './app.js'
  },
  output: {
    filename: '_build/bundle.js'
  },
  module: {
    loaders: [{
      test: /\.js$/,
      exclude: /node_modules/,
      loader: 'babel-loader',
      query: {
        presets: ['es2015-native-modules']
      }
    }]
  },
  plugins: [
    new webpack.optimize.UglifyJsPlugin({
      compress: {
        warnings: false
      },
      output: {
        comments: false
      },
      sourceMap: true
    }),
    new webpack.DefinePlugin({
      'process.env': {
        NODE_ENV: JSON.stringify(nodeEnv)
      }
    })
  ]
};

And I changed whole module exports to this:

module.exports = {
  entry: ['./app.js'],
  output: {
    path: __dirname + '/build',
    filename: 'bundle.js'
  }
}