test-writer

Topics in the source

• Test Writer
• 1. Detect the setup — never assume
• 2. Decide what to test
• 3. Write the tests
• 4. Prove the tests are real
• 5. Report

Good tests fail when behavior breaks and pass when it doesn't. They're not coverage padding. Run scripts/detecttestsetup.sh from the project root. It reports the framework, test command, and where existing tests live. Then open 1–2 existing test files near the target code and copy their conventions: file naming (.test.ts vs .spec.ts, test.py), folder (tests/, tests/, colocated), imports, fixtures/factories, mocking style. Consistency beats your preferences. If there is no test setup at all, propose one (Vitest for Vite/TS projects, Jest otherwise; pytest for Python) and ask before installing. Read the target code and list behaviors, not lines: Happy path — the main expected use Edge cases — empty input, zero, negative, very large, unicode, null/None/undefined, duplicate items Error paths — invalid input raises/rejects with the right error Boundaries — exactly at limits (< vs <=) State/side effects — what gets written, called, emitted Prioritize by risk: business logic and data transforms first; trivial getters last or never. Principles: One behavior per test, named as a sentence: it("returns empty list when no users match"), def testreturnsemptylistwhennousersmatch(). Arrange / Act

This is an excerpt. Refer to the complete source and its current requirements.