Testing

v1.0.0

Reviews test quality across unit, integration, and E2E layers — test isolation, assertion clarity, factory patterns, and coverage gaps. Tests that pass but do not actually verify behavior create false confidence that leads to production incidents.

3 rules

1 categories

Quality(3)

Test Behavior, Not Implementation

Test what the code does (outputs, side effects), not how it does it (internal method calls, private state). Implementation-coupled tests break every time you refactor, even when behavior is unchanged — making tests a liability instead of a safety net.

TestingqualityUnit Testing

HIGH

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Testing Review

A review skill for test code quality, structure, and coverage strategy.

What it covers

Test isolation — no shared mutable state between tests, proper setup/teardown, deterministic ordering
Assertion quality — specific assertions over toBeTruthy, testing behavior not implementation, snapshot discipline
Test structure — arrange/act/assert pattern, descriptive test names, avoiding logic in tests
Factory patterns — test data builders, avoiding hardcoded fixtures, minimal data for each test case
Coverage strategy — critical path coverage, edge cases, error paths, not chasing percentage metrics
E2E discipline — page object patterns, stable selectors, retry-aware assertions

When to use

Run this on any PR that adds or modifies tests. Especially valuable during test suite refactors or when test flakiness becomes a recurring problem.