Awesome

How Jest Mocking Works

This title is a bit misleading. I'm not explaining everything about Jest mocking, just something I wanted to test out and thought was kind of interesting. So it turns out that if you make a call to jest.mock in the root of your module, that mocking will take place before any require statements are resolved/run. This actually makes Jest's mocking capabilities really powerful! It essentially means that you can import all the stuff you would normally, and not worry about whether you're mocking things in time. Pretty legit!

And Christoph comes in to give a little more insight here :) Looks like you can use jest.doMock or jest.dontMock to change this behavior.