Code Safety · interview question
If you wrote a test around mutation and copying, what should the test prove first?
Multiple choiceHardchapter-3-curatedpremiumcode-safetymutation-and-copying
defaults = {"currency": "USD"}
payload = defaults.copy()
payload["currency"] = "EUR"
print(defaults, payload)Answer and explanation
Correct answer
D. That the rule behaves correctly at the boundary cases the lesson is trying to make explicit.
Why
Good tests make the design safer to change because they lock in the meaningful behavior rather than surface-level implementation details.
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