Review my mocking strategy

A test file with more setup than assertions.

Review how the tests below use mocks and test doubles.

1. For each mock, say what it is protecting against: slowness, non-determinism, cost, or an unavailable dependency. If it is none of those, the mock may not be needed.
2. Identify mocks that assert the implementation: verifying that a specific method was called with specific arguments, in a way that would break on a harmless refactor.
3. Find places where so much is mocked that the test can only pass, because nothing real is exercised.
4. Point out any mock whose behaviour has drifted from the real thing, so the test passes while production would fail.
5. Recommend which mocks to replace with a fake, a real instance, or a contract test.

Say which parts of this setup are already right, so I do not rewrite them.

Tests:

Reviewing existing tests. Judging naming, mocking, and whether a test asserts behaviour or just the implementation.