Mocking test data

[jtfirek]

Hey @dawsbot Is this what you are looking for to mock the functions. I have created this draft to see if I am on the right track. This is everything I thought would need to be added for account for this test:

https://github.com/jtfirek/essential-eth/blob/2a34571081d9d136f78931503c9b771d2b5436e0/src/providers/test/json-rpc-provider/get-balance.test.ts

[codecov-commenter]

Codecov Report

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[dawsbot]

Wow yes! This is the exact functionality. The pattern I would prefer instead is to have the mocking done in the test file directly and never using the __mock style because that's easy to lose/confuse in the codebase.

I think the best first-PR here is to find part of the codebase with a simple network request and mock out the network portion. Perhaps getBlock is the right first-example where we do mocking of the fetch and that's all we mock. The test should then work fully offline 🙌

1. Mock the fetch with not jest.fn() but with the actual response from what it would return online (add logging locally first to it then you can remove the logs)
2. Do a jest validation that the mocked fn was called with the valid params

Does this seem reasonable @jtfirek ? If not I can jump in 🙌

[dawsbot]

Actually on second glance these mocks are pretty far off because it entirely removes our ability to test the function in our codebase. We need to mock only the networking part of the test like so: https://jestjs.io/docs/mock-functions#mocking-modules

But in that example they use axios. For essential-eth we would mock isomorphic-unfetch