Test data and fixture generation
Generating edge cases for payloads, tokens, encodings, date formats, regex matches, and parser failures.
Takeaway
Use AI to propose edge cases, then anchor the final fixtures in deterministic utilities and assertions.
01
Ask for categories, not just values
Prompt for empty inputs, malformed inputs, Unicode, boundary lengths, timezone offsets, repeated keys, invalid encodings, and realistic user mistakes. Categories help coverage survive beyond one generated example.
02
Make fixtures deterministic
Generated UUIDs, timestamps, passwords, hashes, and regex samples should be captured in test files once selected. Tests should not depend on a fresh AI answer to remain valid.
03
Tie cases to behavior
Every fixture should prove an expected status, output, error message, or boundary condition. A large fixture list without assertions is noise.