tdd-workshop-exercises/README.md

TDD Workshop - Exercises

A hands-on, 2-hour workshop for learning Test-Driven Development through deliberate practice.

This repository contains the exercise materials for the TDD workshop. Follow the setup guide to prepare before the workshop.

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Before the Workshop

1. Complete Setup

Follow the SETUP_GUIDE.md to:

• Install Dart SDK
• Verify your development environment
• Run a test to confirm everything works

2. Verify Installation

Test that everything is working:

cd password_validator
dart pub get
dart test  # Should see "All tests skipped" or similar

3. Bookmark Reference

Keep TDD_REFERENCE_CARD.md handy during the workshop for quick reference on the RED-GREEN-REFACTOR cycle.

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Repository Structure

tdd-workshop-exercises/
├── README.md (you are here)
├── SETUP_GUIDE.md                     # Setup instructions
├── TDD_REFERENCE_CARD.md              # Quick reference for TDD
│
├── fizzbuzz/                          # Live demo kata (reference)
│   ├── README.md
│   ├── lib/fizzbuzz.dart
│   └── test/fizzbuzz_test.dart
│
├── password_validator/                # Hands-on exercise (Option A)
│   ├── README.md                      # Exercise instructions
│   ├── lib/password_validator.dart    # TODO: Implement here
│   └── test/password_validator_test.dart  # Uncomment tests step-by-step
│
└── shopping_cart/                     # Hands-on exercise (Option B)
    ├── README.md                      # Exercise instructions
    ├── lib/shopping_cart.dart         # TODO: Implement here
    └── test/shopping_cart_test.dart   # Uncomment tests step-by-step

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During the Workshop

Part 1: Live Demo (15 min)

Watch the facilitator demonstrate the RED-GREEN-REFACTOR cycle with FizzBuzz.

The fizzbuzz/ directory contains reference code you can review later.

Part 2: Choose Your Kata (45 min)

Pick one kata to practice:

Option A: Password Validator

• Build a password validator with 5 rules
• Practice rule-based validation
• Discover the Open-Closed Principle through refactoring

Start here: password_validator/README.md

Option B: Shopping Cart

• Build a shopping cart with add, remove, discount
• Practice stateful domain modeling
• Discover when to use Map vs List
• Learn the Value Object pattern

Start here: shopping_cart/README.md

Part 3: Debrief & Reflection (10 min)

Share learnings and discuss design insights with the group.

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The TDD Workflow

For each kata, follow this rhythm:

1. Uncomment the next test
2. Run tests → watch it FAIL (RED)
3. Write minimal code to make it pass (GREEN)
4. Refactor if needed → tests stay GREEN
5. Commit your work
6. Repeat with the next test

Key principles:

• Write the test BEFORE the implementation
• Take small steps (one test at a time)
• Make it work first, make it clean second
• Let the tests drive your design

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Running the Katas

Password Validator

cd password_validator
dart pub get
dart test

Shopping Cart

cd shopping_cart
dart pub get
dart test

FizzBuzz (reference)

cd fizzbuzz
dart pub get
dart test

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Troubleshooting

Having issues? See SETUP_GUIDE.md for:

• Dart installation problems
• dart pub get failures
• Test execution errors
• IDE configuration

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After the Workshop

Continue Practicing

Explore more katas at:

• TDD Katas Collection: https://github.com/dhemasnurjaya/tdd-katas
• Kata-Log: https://kata-log.rocks
• Exercism: https://exercism.org
• Coding Dojo: https://codingdojo.org

Recommended Reading

• Test-Driven Development by Kent Beck
• Clean Code by Robert C. Martin
• Growing Object-Oriented Software, Guided by Tests by Freeman & Pryce

Keep Practicing!

The RED-GREEN-REFACTOR cycle becomes second nature with practice:

1. Start with small, obvious katas
2. Practice the rhythm until it's automatic
3. Gradually tackle more complex problems
4. Focus on letting tests drive design decisions

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Questions?

During the workshop:

• Raise your hand or ask your facilitator
• Don't hesitate to ask for help if you're stuck!

Before the workshop:

• Contact your workshop facilitator
• Verify your setup using SETUP_GUIDE.md

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Philosophy

"Clean code that works." — Ron Jeffries

TDD is a discipline, not a burden:

• Tests first (even for "obvious" code)
• Small steps (one test at a time)
• Refactor fearlessly (tests protect you)

The goal: Build muscle memory for the RED-GREEN-REFACTOR cycle.

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Ready to practice? See SETUP_GUIDE.md to get started!