Angular testing private methods [duplicate]

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• How to write unit testing for Angular 2 / TypeScript for private methods with Jasmine 9 answers

I've built a kinda Queue manager which works with RxJs observables and executes them one by one. Now I want to test this, however all the methods that I want to test are private.

Public interface has only two methods that create an observable and add it to the queue manager.

If I try to make something like spyOn(myService, 'privateMethod') PhpStorm analysis says that it is not assignable to type (and refers to public methods).

I can't extract this into something where these would become public because it's a complicated logic which should not be interrupted from the outside.