Worthless roundtrip property
You asked an AI to write a Hypothesis property-based test for a serialize/deserialize pair for a config object. It produced:
It passes thousands of cases. Why is this property nearly worthless, what is the property you actually want, and what subtlety must you get right for round-trip properties?
Implement
roundtrip_mismatches(entries: list[str]) → list[str]Examples
in
[["host=localhost","port=8080"]]out[]in
[["motd=hello;world"]]out["motd","world"]in
[[]]out[]What a strong answer looks like
Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it (tests, edge cases, reading critically), and how you’d re-prompt or decompose to get it right.
0:00 of about 20 min
Vibe & agentic: describe the solution in plain language (or narrate it) and the coach grades your approach.
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.