jest-alias-module-loader

Jest doesn't really have a simple way of globally replacing certain modules, but I've come up with a couple. Firstly, the hacky and gross way to replace modules is by using a regexp replace in the preprocessor. But let's not do that. Instead, this module extends the default HasteModuleLoader to allow us to alias some modules at require time:

1// test/aliasedModuleLoader.js
2
3var JestAliasModuleLoader = require('jest-alias-module-loader');
4
5module.exports = JestAliasModuleLoader({
6   aliasedModules: {
7    // use compiled react for faster loading
8    'react': 'react/dist/react-with-addons',
9    'react/addons': 'react/dist/react-with-addons',
10  },
11});

To use this, just add a line to your Jest config (eg. in package.json):

1{
2  "jest": {
3    "moduleLoader": "<rootDir>/test/aliasedModuleLoader.js"
4  }
5}