" I want to explain some of the terms that fly around like fake, mock, shim or stub.

    Fake is a general term and can include stubs, mocks, and shims.
    Stub provides pre-set answers to calls.
    Mock checks interactions and provides pre-set answers.
    Shim diverts or changes the behavior of existing calls.

"

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" Creating your own fakes comes with a cost. You have to maintain them... "