Adding aliases and root in resolve will not work in tests.

[AlexFrazer]

The errors:

If you add any aliases or root to the webpack.config.base.js, it will not function the same in a test environment, and will not resolve appropriately. The error will be something like:

Error: Cannot find module 'app/utils/api'

How to reproduce:

Simply add a single alias or root to the webpack.config.base.js

export default {
  // ... whatever
  resolve: {
    extensions: ['', '.js', '.jsx', '.json', '.css', '.scss'],
    packageMains: ['webpack', 'browser', 'web', 'browserify', ['jam', 'main'], 'main'],
    alias: { 'app': `${__dirname}/app` },
  }
}

Then add this to the webpack.config.test.js

module.exports = {
  // ...
  resolve: devConfig.resolve
}

Use an aliased import anywhere in the application and import it in a test.

import 'app/utils/api';  // <- just an example.

Run tests.

$ npm run test

[jhen0409]

Write resolve.alias to test config and add babel-plugin-webpack-aliases to TEST env of babelrc may be a simple workaround.

(See istarkov/babel-plugin-webpack-loaders#68)

.babelrc

{
  ...
  "env": {
    ...
    "test": {
      "plugins": [
+       ["webpack-aliases", { "config": "webpack.config.test.js" }],
        ["webpack-loaders", { "config": "webpack.config.test.js", "verbose": false }]
      ]
    }
  }
}