Unit testing static method that imports environment file
If you really want to unit test that logic, you should fake its data. In order to do that, you need a way to inject that dependency instead of getting it straight from it.

You have 3 options:


Installing a framework to mock the import (as detailed in https://medium.com/@emandm/import-mocking-with-typescript-3224804bb614)
Have a constructor that is autocalled for its usage statically.
Similar to number 2: have a method with environment as parameter (so you can test it), and the current one calls the new one with the imported environment as parameter.