Antipattern: Mock-Heavy Tests

The smell

• Tests with more mock / stub / expect(...).to receive(...) lines than assertions
• Models, mailers, and jobs all stubbed out — no real DB activity
• Tests that pass while production breaks (mock/reality drift)
• Refactors break unrelated tests because mocks know too much

Why it hurts

• Tests describe collaboration mechanics, not behavior
• New devs can't read the test as a spec for the system
• Refactors break tests that have nothing to do with the refactor
• Hides design problems (anemic models, excessive DI)