# TDD Workshop

**A hands-on, 80-minute workshop for learning Test-Driven Development through deliberate practice.**

---

## Workshop Overview

This workshop teaches the RED-GREEN-REFACTOR cycle through:
1. **Live demonstration** (FizzBuzz kata)
2. **Hands-on practice** (Password Validator or Shopping Cart)
3. **Group reflection** and retrospective

**Target audience:** 3-person team (2 developers + facilitator)  
**Duration:** 80 minutes  
**Language:** Dart

---

## Repository Structure

```
tdd-workshop/
├── README.md (you are here)           # Workshop overview
├── WORKSHOP_PLAN.md                   # Complete facilitator schedule & scripts
├── FACILITATOR_GUIDE.md               # Quick reference for facilitators
├── TDD_REFERENCE_CARD.md              # One-page handout for participants
├── SETUP_GUIDE.md                     # Installation & troubleshooting
│
├── fizzbuzz/                          # Live demo kata
│   ├── README.md                      # Kata overview
│   ├── DEMO_SCRIPT.md                 # Step-by-step demo guide (15 min)
│   ├── lib/fizzbuzz.dart              # Final implementation
│   └── test/fizzbuzz_test.dart        # Progressive tests
│   └── .git/                          # Git history shows TDD progression!
│
├── password_validator/                # Hands-on exercise (Option A)
│   ├── README.md                      # Exercise instructions
│   ├── DEMO_SCRIPT.md                 # Facilitator reference guide
│   ├── lib/
│   │   ├── password_validator.dart    # Starter code (TODO)
│   │   └── password_validator_solution.dart  # Reference solution
│   └── test/
│       └── password_validator_test.dart      # Tests to uncomment step-by-step
│
└── shopping_cart/                     # Hands-on exercise (Option B)
    ├── README.md                      # Exercise instructions
    ├── DEMO_SCRIPT.md                 # Facilitator reference guide
    ├── lib/
    │   ├── shopping_cart.dart         # Starter code (TODO)
    │   └── shopping_cart_solution.dart       # Reference solution
    └── test/
        └── shopping_cart_test.dart           # Tests to uncomment step-by-step
```

---

## For Facilitators

### Quick Start

1. **Read the plan:**
   - Start with `WORKSHOP_PLAN.md` for complete details
   - Review `FACILITATOR_GUIDE.md` for quick reference
   - Study `fizzbuzz/DEMO_SCRIPT.md` for the live demo
   - Review kata demo scripts:
     - `password_validator/DEMO_SCRIPT.md` (reference for helping stuck participants)
     - `shopping_cart/DEMO_SCRIPT.md` (reference for helping stuck participants)

2. **Practice the demo:**
   ```bash
   cd fizzbuzz
   git log --oneline  # See the RED-GREEN-REFACTOR commits
   ```
   Each commit shows one step of the TDD cycle.

3. **Prepare materials:**
   - See "Pre-Workshop Preparation" in `WORKSHOP_PLAN.md`
   - Share `SETUP_GUIDE.md` with participants 1 week before
   - Have `TDD_REFERENCE_CARD.md` ready to share

4. **Day of workshop:**
   - Arrive 15 minutes early
   - Test projector/screen sharing
   - Write schedule on whiteboard
   - Have solution files ready (don't share early!)

### Key Documents

| Document | Purpose |
|----------|---------|
| **WORKSHOP_PLAN.md** | Complete schedule, scripts, checklists |
| **FACILITATOR_GUIDE.md** | Quick reference, kata insights |
| **fizzbuzz/DEMO_SCRIPT.md** | Minute-by-minute live demo walkthrough |
| **password_validator/DEMO_SCRIPT.md** | Reference guide for helping stuck participants |
| **shopping_cart/DEMO_SCRIPT.md** | Reference guide for helping stuck participants |
| **TDD_REFERENCE_CARD.md** | Participant handout (print or share digitally) |
| **SETUP_GUIDE.md** | For participants before workshop |

---

## For Participants

### Before the Workshop

1. **Complete setup:** Follow `SETUP_GUIDE.md` to install Dart and verify tests run
2. **Verify installation:**
   ```bash
   cd password_validator
   dart pub get
   dart test  # Should see "All tests skipped" or passing
   ```
3. **Bookmark reference:** Have `TDD_REFERENCE_CARD.md` ready during the workshop

### During the Workshop

1. **Watch the live demo** — See RED-GREEN-REFACTOR in action (FizzBuzz)
2. **Choose a kata:**
   - **Password Validator:** Rules-based validation, interesting refactoring
   - **Shopping Cart:** Stateful domain object, data structure decisions
3. **Follow the 3-Way Ping-Pong workflow:**
   - **Dev A (RED):** Uncomment one test, run it, watch it fail. Pass the keyboard.
   - **Dev B (GREEN):** Write minimal code to pass. Pass the keyboard.
   - **Dev C (REFACTOR):** Clean up the code. Write the next test (RED). Pass the keyboard.
   - Rotate roles and repeat

### Kata Instructions

#### Password Validator
- Open `password_validator/README.md` for instructions
- Implement validation rules one at a time
- Step 6 is the refactoring challenge (rules as data)

#### Shopping Cart
- Open `shopping_cart/README.md` for instructions
- Build a shopping cart with add, remove, total, discount
- Discover when to use Map vs List (Step 3)
- Learn Value Object pattern (Step 5)

---

## What You'll Learn

### The TDD Rhythm
- **RED:** Write a failing test (proves it can fail)
- **GREEN:** Write minimal code to pass (make it work)
- **REFACTOR:** Clean up code (make it right)
- **REPEAT:** Next test

### Design Insights

Through hands-on practice, you'll discover:

**Password Validator:**
- How duplication in tests reveals duplication in code
- Rules as data (Open-Closed Principle)
- Refactoring with tests as a safety net

**Shopping Cart:**
- How tests drive data structure choices (List → Map)
- Value Objects for validation
- Stateful domain modeling

**General:**
- Tests as living documentation
- Design emerges from simple tests
- Small steps lead to robust solutions

---

## After the Workshop

### Continue Practicing

Explore the **tdd-katas** repository for more practice:
https://github.com/dhemasnurjaya/tdd-katas

It contains 5 complete katas with git commit history showing every RED-GREEN-REFACTOR step:
1. **Roman Numerals** — Table-driven algorithms
2. **Bowling Game** — State management and look-ahead logic
3. **Gilded Rose** — Refactoring legacy code safely
4. **String Calculator** — Bug hunting with TDD
5. **Mars Rover** — Command pattern and value objects

### Resources

**Reference materials:**
- `TDD_REFERENCE_CARD.md` — Quick reference for TDD practice

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

**Online practice:**
- Kata-Log: https://kata-log.rocks
- Exercism: https://exercism.org
- Coding Dojo: https://codingdojo.org

---

## Running the Katas

### Password Validator
```bash
cd password_validator
dart pub get
dart test
```

### Shopping Cart
```bash
cd shopping_cart
dart pub get
dart test
```

### FizzBuzz (Demo)
```bash
cd fizzbuzz
dart pub get
dart test

# See TDD progression through git history
git log --oneline
```

---

## Troubleshooting

See `SETUP_GUIDE.md` for detailed troubleshooting of common issues:
- Dart installation problems
- `dart pub get` failures
- Test execution errors
- IDE setup

---

## Questions?

**For facilitators:**
- Review `WORKSHOP_PLAN.md` for comprehensive guidance
- Check `FACILITATOR_GUIDE.md` for kata-specific insights

**For participants:**
- During workshop: Raise your hand or ask facilitator
- Before workshop: Contact your facilitator with setup questions
- After workshop: Continue practicing with tdd-katas repository

---

## Philosophy

> "Clean code that works." — Ron Jeffries

TDD is a **discipline**, not a burden. The rhythm becomes automatic with practice:
- 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.

---

## License

This workshop material is provided for educational purposes. Feel free to adapt and use for your own workshops.

---

**Ready to start? Facilitators: See `WORKSHOP_PLAN.md`. Participants: See `SETUP_GUIDE.md`.**