TDD Mastery

Core Cycle: Red-Green-Refactor

1. Red - Write a failing test that defines the desired behavior
2. Green - Write the minimum code to make the test pass
3. Refactor - Clean up while keeping tests green

Never write production code without a failing test first. Each cycle should take 2-10 minutes.

Test Structure

Use the Arrange-Act-Assert pattern consistently:

Arrange: Set up test data and dependencies
Act:     Execute the behavior under test
Assert:  Verify the expected outcome