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TFS Build: Running your JavaScript unit tests during build

To run our JavaScript unit tests(you have them right?) inside Visual Studio we are using Chutzpah. Chutpzah is a JavaScript test runner which enables you to run unit tests using QUnit, Jasmine, Mocha, CoffeeScript and TypeScript(!).

Chutzpah has a test adapter for the Visual Studio Unit Test Explorer which makes it possible to run your JavaScript unit tests among your other tests.

This week I spent some time in making these tests also work on the build server. Here are some of the lessons I learned among the way:

Tip 1  - Add the Chutzpah nuget package as a reference to your unit test project

Add the Chutzpah nuget package to the project that contains your JavaScript unit tests. This NuGet package contains all required DLL’s and tooling to be able to run your JavaScript tests. By using this approach you don’t need to install the Chutzpah test adapter on your build server or specify the location of your test adapter. The TFS Build testing tools will automatically detect the required DLL’s and load the test adapter for you.

Tip 2 – Start using a chutzpah.json file

Chutpzah uses a lot of defaults out-of-the-box. But you have the option to tweak and configure almost everything. The Chutzpah test runner will search for this configuration file in all your test directories and multiple config files can be used.

Here is the config file that we are using:

More information: https://github.com/mmanela/chutzpah/wiki/Chutzpah.json-Settings-File 

Tip 3 – Remember the ‘IsTestFrameworkFile’ configuration option

As you can see in the config file above, we are using Angular at the moment. However the first time when we tried to run it using the chutzpah.json file, we got the following error:

“ReferenceError: ‘module’ is undefined”

This was caused by the fact the Angular and Angular.mock file were not yet loaded. You can fix this by setting the “IsTestFrameworkFile” option to “True”. This ensures that the references will be placed directly after the test framework files (like Jasmine.js) in the test harness.

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