Fix Angular Error: Cannot set base providers because it has already been called

Those of you who are getting into angular testing, normally face this error. Usually this happen when we set the testing environment for Angular. These are the lines

These are the culprits

TestBed.initTestEnvironment(
  BrowserDynamicTestingModule,
  platformBrowserDynamicTesting()
) 
// or wrapped in beforeAll 
beforeAll(() {
  TestBed.initTestEnvironment(
    BrowserDynamicTestingModule,
    platformBrowserDynamicTesting()
  )
})

Diagnosing & Solution

I might not have written this post if the error message was easy to understand

Your test might run just fine, even if this error occurs. All it says that above lines ran twice in your codebase.

Just look at the tests.ts file

Now let’s see the actual content of test.ts. I really don’t know whether this configuration came from the beginning. Or were they added in recent angular version i-e version 6

So next time don’t include them in your jasmine beforeEach block of your spec files