aaa-pattern
AAA Pattern (Arrange-Act-Assert)
Overview
Every test has three phases: Arrange, Act, Assert. Keep them separate.
Clear structure makes tests readable, maintainable, and debuggable. When phases blur together, tests become confusing.
When to Use
- Writing any test
- Test logic is hard to follow
- Unclear what's being tested
- Multiple actions or assertions mixed together
The Iron Rule
EVERY test must have clearly separated Arrange, Act, and Assert phases.
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