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Run tests with Testem in a convenient way:

  • Multi-environment runs ❤️
  • Out-of-box support for Coffee, Ejs, JST, ... 💚
  • Built-in support of Mincer 💙

Getting Started

This plugin requires Grunt ~0.4.0

If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:

npm install grunt-testem-mincer --save-dev

Once the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:


How to use

Environments and tasks

Within your Grunt configuration you have to define one or more environments that Testem will run with:

  testem: {
    environment1: {
      // List of files to attach
      src: [
      // Options that will be passed to Testem
      options: {
        parallel: 8,
        launch_in_ci: ['PhantomJS', 'Firefox', 'Safari'],
        launch_in_dev: ['PhantomJS', 'Firefox', 'Safari']
    environment2: {
      // ...

In the example given we pass coffee files straight into the src and there's no mistake in that. grunt-testem-mincer will chew it for you :godmode:.

There are two modes that you can run tests at:

  • grunt testem:ci:<environment> command-line CI mode
  • grunt testem:run:<environment> Development mode where Testem watches for modifications of files to rerun tests on your behalf

The default grunt testem task runs all settled environments one by one in CI mode.

Available options

Every environment can take 4 arguments which are:

  • src: the full list of files to run (allows unix glob masks: "path/**/."). Files get included into playground in the order they are listed at the array.
  • options: options that get passed to running instance of Testem (they are typically located at Testem config)
  • assets: options that can be used to configure internal instance of Mincer preprocessor
  • report_file: file path location for the output report file which is produced from running Testem.

Testem options

The full list of options you can use to affect Testem instance is available at Testem documentation.

Note also that you can use JS function as hooks:

  testem: {
    environment1: {
      src: '*.js'
      options: {
        before_tests: function (config, data, callback) {
          data;         // {}
          config;       // ... resulting Testem config
          callback();   // call to finalize hook
        on_change: function (config, data, callback) {
          data;         // {file: '...'}
          config;       // ... resulting Testem config
          callback();   // call to finalize hook

Preprocessor options

  • assets.port: port that preprocessing server will listen at (defaults to 7358)
  • assets.setup: callback to use to setup instance of mincer. Gets instance of Mincer.Environment as a first parameter and Mincer itself as a second.

Advanced usage

Internally grunt-testem-mincer is powered by Mincer and it allows you to organize testing of almost any kind of code no matter how exactly it is organized and what preprocessing it requires. This is exactly how it works:

During initialization, plugin setups local Mincer server with project root as an inclusion path. Then it substitutes local paths with URLs served through it. So instead of passing spec/ to Testem (that will not work obviously), it passes http://localhost:7358/spec/ and Mincer takes care of the rest. It also intelligently passes proper watch_files option to Testem so no worries – autoreload works just fine.

What does it mean in other words? It means you can utilize Mincer during the building of your specs or application files. You can use any directives and any Engines it has to offer you (or even write your own). And all that complexity will work blazing fast thanks to built-in Mincer caching! 😱

So go ahead, take a look at these samples...

... and hurry up to start using it!


Huge thanks goes to Toby Ho, the original author of Testem that was one by one accepting my pull-requests and modifications that made such integration possible.



Copyright 2013 Boris Staal

It is free software, and may be redistributed under the terms of MIT license.

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