Jest

If you use Jest to run your tests, you need additional configuration because Jest is running on a Node.js emulator.

Taiga UI uses @ng-web-apis/common to avoid accessing global variables like window or navigator directly. Which requires Server Side Rendering (SSR) with the help of its sister library @ng-web-apis/universal for Jest to run properly.

Otherwise, you're gonna face errors like ReferenceError: IntersectionObserver is not defined

Using @angular-builders/jest or jest-preset-angular

If you're using one of these libraries. You can follow the following steps :

1. Install npm i @ng-web-apis/universal --save-dev (install it as a devDependency only if you will use it for Jest, otherwise install it as a regular dependency). Install 2.0 and above for Taiga UI 3.0 and above, otherwise install 1.x.x.
2. Add a setupFilesAfterEnv property to your jest.config.ts or package.json jest configuration (depending on where your configuration is) with the path to setup-jest.ts if you have not already.

   jest.config.ts

       
       
   
           
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   or

   package.json

       
       
   
           
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3. Create the file setup-jest.ts (wherever you want as long as it's at the path referenced above) if you have not already. For example here at the root of the project.
4. Add the following line to the setup-jest.ts : import '@taiga-ui/testing/setup-jest'; .

   setup-jest.ts

       
       
   
           
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