Choose and record a testing strategy before writing tests or affected implementation, then guide observable RED/GREEN/refactor and independent review. Use for behavior changes, regression tests, test doubles, testability seams, static TypeScript contracts or unreliable tests. Runner-neutral catalog with a qualified Vitest adapter, an implemented Karma + jasmine-core + Angular TestBed adapter and an implemented Codeception adapter. Companion to review-testing-patterns. Excludes prose-only and formatting-only changes.
