Eurystheus

A library to write stable, readable and beautiful tests.

How to use it?

You need to wrap your jest mock function with the when function. Now you can use mockX on the result. For example, if we have a mock function that should return 1 when called with "foo" this how we should set it in the code. When calling mockFunction in this code it will return 1 if called with "foo" and undefined if called with anything else.

const mockFunction = jest.fn();
when(mockFunction).calledWith("foo").mockReturnValue(1);

Why Eurystheus?

Just like the greek king that tested Hercules in the famous mythology, this library is helping to test stuff and make sure it's all working as expected.