tdd

TDD Workflow

Implement using strict Test-Driven Development.

Process

1. RED - Write Failing Test First

• Write ONE test that describes expected behavior
• Run test - confirm it FAILS for the right reason
• Show test to user before proceeding

2. GREEN - Minimum Code to Pass

• Write the MINIMUM code to make test pass
• No extra features, no optimization
• Run test - confirm it PASSES

3. REFACTOR - Improve Code

• Clean up code while keeping tests green
• Apply patterns and best practices
• Run tests after each change

4. REPEAT

• Move to next requirement
• Write next failing test
• Continue cycle

My Role

When asked to implement a feature:

1. Ask for requirements if not clear
2. Write the test first - show it to user
3. Run the test - confirm it fails
4. Implement minimum code to pass
5. Refactor if needed
6. Repeat for next requirement

Rules

• NEVER write production code without a failing test
• ONE test at a time
• Tests must fail before implementation
• Keep cycles short (< 10 minutes each)

Test Naming

methodName_scenario_expectedResult

Examples:

• create_withValidData_returnsUser
• findById_notFound_throwsException

Test Quality Checks

• Test name follows: method_scenario_expected
• Test has Given-When-Then structure
• One concept per test
• No logic in tests
• Tests are independent

Commands

# Java/Maven
mvn test -Dtest=ClassName#methodName

# Node.js/Vitest
npx vitest run --reporter=verbose

# Run specific test
npx vitest run path/to/test.ts

Never Do

• Write production code before tests
• Write multiple tests before implementing
• Skip the refactor phase
• Leave tests incomplete

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Start by asking: "What behavior should we test first?"