Write exactly 5 pytest tests for your team's parser

About this exercise

Your group project uses the parse_duration helper below, and your team agreed on 5 edge cases to test: an empty string raises ValueError, '0s' returns 0, '1h30m' returns 5400, '90s' returns 90, and uppercase '1H' raises ValueError. Write exactly 5 plain pytest functions, one per case, importing only pytest and parse_duration, in exactly 1 code block of at most 20 lines, with under 20 words of text.

Common mistakes when you ask AI for this

• Getting a giant test suite. Asked for tests, the AI writes 10 to 20 of them, often parametrized, covering cases your team didn't pick. Try: Say: "Exactly 5 plain test functions, one per case, no parametrize."
• Not listing the cases. The AI picks its own edge cases unless you name the 5 your team agreed on. Try: List them: "'' raises ValueError, '0s' -> 0, '1h30m' -> 5400, '90s' -> 90, '1H' raises ValueError."
• Extra imports and helpers. The AI may import parametrize helpers or test the future '1.5h' idea. Try: Add: "Import only pytest and parse_duration from durations. Nothing else."
• A tutorial around the code. By default the AI explains how to run pytest and what each test does. Try: Add: "Only the code block, no text."

What a strong prompt includes

• Sets the number of tests
• Lists the agreed cases
• Rules out parametrize and classes
• Limits imports
• Asks for only code

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