When to use Snapshots Jest offers a great feature called Snapshot Testing. The known 3rd party adapters are: Adapter Package For Library Status stable work in progress Running Enzyme Tests Enzyme is unopinionated regarding which test runner or assertion library you use, and should be compatible with all major test runners and assertion libraries out there. Async tests For some examples of writing asynchronous tests see the post. Here is the entire test set up code. Any idea why this could happen? Example 2: You just started writing a new component and are writing tests as you go.
This will create window globally. I recommend avoiding Snapshots at first. Global properties by adding interface and redefining the global variable with global Node variable. Example 1: You have a utility function that returns a random string. Could not create controller error has a few different reasons. For instance, enzyme-adapter-react-16 has peer dependencies on react and react-dom.
Instead, I recommend testing that the string is the proper length and made up of the correct types of characters based on the type of string being generated. Using chai for assertion library. MediaController not found, there is something wrong with the actual controller code. It brings the PowerShell scripting capabilities to deliver Sitecore solutions faster. All examples in the documentation will be provided using and , although neither library is a dependency of enzyme. Check out our for help moving on to Enzyme v3 where React 16 is supported. Are you currently using Enzyme 2.
Another common reason is the inner …. You cannot test this with Snapshots as it will be different each time. The complete example can be found on. . This post focuses on setting up the test environment with Mocha for. Newly created globalNode object has window, document and navigator properties. The following command assumes you're using React 16.
Installation enzyme should be installed using npm: npm i --save-dev enzyme enzyme can be used with your test runner of choice. Working with React 16 If you are wanting to use enzyme with React 16, but don't already have React 16 and react-dom installed, you should do so: npm i --save react 16 react-dom 16 Next, to get started with enzyme, you can simply install it with npm: npm i --save-dev enzyme enzyme-adapter-react-16 And then you're ready to go! Snapshots provide a form of regression testing. When I set this up first time, it took me a long time to figure out why TypeScript is complaining about things like window does not exist on type Global or mount method not working because a global document is not loaded. This doesn't remove production mode. The documentation and examples for enzyme use and , but you should be able to extrapolate to your framework of choice. We first need to add types for required browser environment properties by extending interface and adding properties.
For instance, if you are using enzyme with React 16, you can run: npm i --save-dev enzyme enzyme-adapter-react-16 Each adapter may have additional peer dependencies which you will need to install as well. Then run one of the following commands depending on whether you use Yarn or npm to install Jest as a dev dependency. Then switch over to using Snapshots. To do this, you can use the top level configure. At the moment, Enzyme has adapters that provide compatibility with React 16.
However, once you get your head around it, it becomes easier. Example: I type npm install --save-dev jest enzyme enzyme-adapter-react-16 These packages appear in package. You can also manipulate, traverse, and in some ways simulate runtime given the output. Most of the common modules has types available these days. To get started with enzyme, you can simply install it via npm. Later, you need to register ts-node in the mocha command.
If you're using a different version then make sure to install the Enzyme adapter for the version you're using. Instead polish the component and get it close to what you know it will be. But, getting this work helped me to understand TypeScript a little bit better. I had to go and set it explicitly again to undo production. So, you can simply install the regular module as well as the one prefixed with types.