Tdd Workflow

1---
2name: tdd-workflow
3description: Test-Driven Development workflow principles. RED-GREEN-REFACTOR cycle.
4allowed-tools: Read, Write, Edit, Glob, Grep, Bash
5---
6 
7# TDD Workflow
8 
9> Write tests first, code second.
10 
11---
12 
13## 1. The TDD Cycle
14 
15```
16🔴 RED → Write failing test
17    ↓
18🟢 GREEN → Write minimal code to pass
19    ↓
20🔵 REFACTOR → Improve code quality
21    ↓
22   Repeat...
23```
24 
25---
26 
27## 2. The Three Laws of TDD
28 
291. Write production code only to make a failing test pass
302. Write only enough test to demonstrate failure
313. Write only enough code to make the test pass
32 
33---
34 
35## 3. RED Phase Principles
36 
37### What to Write
38 
39| Focus | Example |
40|-------|---------|
41| Behavior | "should add two numbers" |
42| Edge cases | "should handle empty input" |
43| Error states | "should throw for invalid data" |
44 
45### RED Phase Rules
46 
47- Test must fail first
48- Test name describes expected behavior
49- One assertion per test (ideally)
50 
51---
52 
53## 4. GREEN Phase Principles
54 
55### Minimum Code
56 
57| Principle | Meaning |
58|-----------|---------|
59| **YAGNI** | You Aren't Gonna Need It |
60| **Simplest thing** | Write the minimum to pass |
61| **No optimization** | Just make it work |
62 
63### GREEN Phase Rules
64 
65- Don't write unneeded code
66- Don't optimize yet
67- Pass the test, nothing more
68 
69---
70 
71## 5. REFACTOR Phase Principles
72 
73### What to Improve
74 
75| Area | Action |
76|------|--------|
77| Duplication | Extract common code |
78| Naming | Make intent clear |
79| Structure | Improve organization |
80| Complexity | Simplify logic |
81 
82### REFACTOR Rules
83 
84- All tests must stay green
85- Small incremental changes
86- Commit after each refactor
87 
88---
89 
90## 6. AAA Pattern
91 
92Every test follows:
93 
94| Step | Purpose |
95|------|---------|
96| **Arrange** | Set up test data |
97| **Act** | Execute code under test |
98| **Assert** | Verify expected outcome |
99 
100---
101 
102## 7. When to Use TDD
103 
104| Scenario | TDD Value |
105|----------|-----------|
106| New feature | High |
107| Bug fix | High (write test first) |
108| Complex logic | High |
109| Exploratory | Low (spike, then TDD) |
110| UI layout | Low |
111 
112---
113 
114## 8. Test Prioritization
115 
116| Priority | Test Type |
117|----------|-----------|
118| 1 | Happy path |
119| 2 | Error cases |
120| 3 | Edge cases |
121| 4 | Performance |
122 
123---
124 
125## 9. Anti-Patterns
126 
127| ❌ Don't | ✅ Do |
128|----------|-------|
129| Skip the RED phase | Watch test fail first |
130| Write tests after | Write tests before |
131| Over-engineer initial | Keep it simple |
132| Multiple asserts | One behavior per test |
133| Test implementation | Test behavior |
134 
135---
136 
137## 10. AI-Augmented TDD
138 
139### Multi-Agent Pattern
140 
141| Agent | Role |
142|-------|------|
143| Agent A | Write failing tests (RED) |
144| Agent B | Implement to pass (GREEN) |
145| Agent C | Optimize (REFACTOR) |
146 
147---
148 
149> **Remember:** The test is the specification. If you can't write a test, you don't understand the requirement.
150