Implementation & TDD

Implementation & TDD Skill

TDD 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 the code while keeping tests green
4. REPEAT

When to Use TDD

• Always TDD: Business logic, data transformations, validation rules
• Sometimes TDD: UI components (test behavior, not layout), API handlers
• Skip TDD: Config files, type definitions, simple glue code

Test-First Template

describe('[Feature/Function name]', () => {
  it('should [expected behavior] when [condition]', () => {
    // Arrange
    const input = /* setup */;

    // Act
    const result = functionUnderTest(input);

    // Assert
    expect(result).toBe(/* expected */);
  });

  it('should [error behavior] when [error condition]', () => {
    // Arrange & Act & Assert
    expect(() => functionUnderTest(badInput)).toThrow(/* expected error */);
  });
});

Git Worktree Workflow

Setup

# From the epic branch, create a worktree for your task
git worktree add ../worktrees/${AGENT_NAME}-task-${TASK_ID} ${EPIC_BRANCH}

# Move into your worktree
cd ../worktrees/${AGENT_NAME}-task-${TASK_ID}

# Create your feature branch
git checkout -b ${AGENT_NAME}/task-${TASK_ID}-${TASK_SLUG}

During Work

# Regular commits as you work
git add <specific-files>
git commit -m "feat(scope): description of change"

# Keep up to date with epic branch
git fetch origin
git rebase ${EPIC_BRANCH}

Submitting for Review

# Ensure tests pass
npm test  # or project-specific test command

# Push your branch
git push -u origin ${AGENT_NAME}/task-${TASK_ID}-${TASK_SLUG}

Cleanup After Merge

# After QA approval and merge
cd ..
git worktree remove worktrees/${AGENT_NAME}-task-${TASK_ID}
git branch -d ${AGENT_NAME}/task-${TASK_ID}-${TASK_SLUG}

Commit Message Convention

type(scope): brief description

[optional body with more detail]

[optional footer]