🧪 TDD Masterclass

Welcome to the TDD Masterclass! In this tutorial, you'll master the art of test-driven development using ECC's tdd-guide agent.

🎯 What is TDD?

Test-Driven Development (TDD) is a software development methodology where you:

1. 🔴 Red Phase - Write a failing test first
2. 🟢 Green Phase - Write the minimum code to make it pass
3. 🔵 Refactor Phase - Improve the code without changing behavior

This cycle ensures your code is always tested and you only build what's truly needed.

🎮 Try the TDD Commands

ECC Command Simulator

❯

Available Commands:

📚 The Red-Green-Refactor Cycle

TDD Cycle: Building a Calculator

Step 1 of 4

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🔴 Red: Write a Failing Test

First, write a test for functionality that doesn't exist yet. This test must fail.

// calculator.test.ts
import { add } from './calculator'

describe('Calculator', () => {
it('should add two numbers', () => {
  expect(add(2, 3)).toBe(5)
})
})

💡Run the test now — it should fail because add() doesn't exist yet!

💻 Interactive Code Lab

Try writing your own TDD cycle! Start with a failing test:

TDD Lab: String Utilitiestypescript

// Step 1: Write a failing test // Test: capitalize('hello') should return 'Hello' import { capitalize } from './stringUtils' describe('StringUtils', () => { it('should capitalize first letter', () => { expect(capitalize('hello')).toBe('Hello') }) }) // Step 2: Now write the function to make the test pass! // export function capitalize(str: string): string { // // Your code here // }

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🎯 TDD Best Practices

Do ✅

• Write the smallest possible test first
• Run tests frequently (after every change)
• Commit after each green phase
• Keep refactoring sessions short
• Give tests descriptive names

Don't ❌

• Write implementation code before writing tests
• Write multiple tests at once
• Skip the refactoring phase
• Test implementation details
• Make tests too complex

❓ Knowledge Check

❓

In TDD, when should you write implementation code?

ABefore writing any tests

BAfter writing a failing test

CAt the beginning of the project

DOnly during code review

❓

What should you do during the refactoring phase?

AAdd new features

BWrite more tests

CImprove code quality without changing behavior

DDelete failing tests

❓

How long should a typical TDD cycle take?

A1-2 hours

B30-60 minutes

C5-10 minutes

DAn entire day

🎉 Congratulations!

You've completed the TDD Masterclass! You learned:

• ✅ The Red-Green-Refactor cycle
• ✅ TDD best practices
• ✅ How to use the /tdd command in ECC
• ✅ Writing effective tests

📖 Next Steps

Check out the Interactive Tutorials section for more tutorials!