Testing · Senior · Question 59 of 75

When is verifying interactions (that a mock was called) the right assertion?

✓Correct answer: When the call itself is the outcome - sending analytics, an email, a payment request at a boundary
2Always - it's the most precise assertion
3Never - always check state

Explanation

For internal collaborators, prefer checking the observable result.

Further reading

Martin Fowler: Mocks Aren't Stubs ↗

Test yourself

Take the Testing · Senior quiz: questions and options are shuffled, and you get a review of your mistakes at the end.