detect-test-smells - SKILL.md Agent Skill

name: detect-test-smells description: Detects test antipatterns and code smells in PHP test suites. Identifies 15 smells (Logic in Test, Mock Overuse, Fragile Tests, Mystery Guest, etc.) with fix recommendations and refactoring patterns for testability.

Test Smell Detection

Identifies antipatterns and code smells in PHP test suites.

15 Test Smells

#	Smell	Severity	Detection Pattern
1	Logic in Test	High	`if/for/while/foreach` in tests
2	Mock Overuse	High	>3 mocks in single test
3	Test Interdependence	High	`static $`, `@depends`
4	Fragile Test	High	`expects(exactly)`, `at()`
5	Mystery Guest	Medium	`file_get_contents`, `getenv`
6	Eager Test	Medium	Multiple unrelated assertions
7	Assertion Roulette	Medium	>5 assertions without context
8	Obscure Test	Low	`test_it_works`, `test_foo`
9	Test Code Duplication	Medium	Repeated setup/assertion
10	Conditional Test Logic	Medium	`if.*assert` patterns
11	Hard-Coded Test Data	Low	Magic values in tests
12	Testing Private Methods	High	`setAccessible(true)`
13	Slow Test	Medium	`sleep`, I/O in unit tests
14	Mocking Final Classes	High	Mock concrete final classes
15	Mocking Value Objects	High	Mock readonly/immutable classes

Quick Detection Commands

# Logic in tests
Grep: "if \(|for \(|while \(|foreach \(" --glob "tests/**/*Test.php"

# Mock overuse (manual count needed)
Grep: "createMock|createStub" --glob "tests/**/*Test.php"

# Test interdependence
Grep: "static \$|@depends" --glob "tests/**/*Test.php"

# Testing private methods
Grep: "setAccessible\(true\)|ReflectionMethod" --glob "tests/**/*Test.php"

# Mystery guest
Grep: "file_get_contents|fopen|getenv|_ENV|_SERVER" --glob "tests/**/*Test.php"

# Fragile tests
Grep: "expects\(.*exactly|expects\(.*at\(" --glob "tests/**/*Test.php"

Output Format

# Test Smell Report

## Summary

| Smell | Count | Severity |
|-------|-------|----------|
| Logic in Test | 5 | High |
| Mock Overuse | 3 | High |

## Findings

### Logic in Test (5 occurrences)

| File | Line | Code |
|------|------|------|
| OrderTest.php | 45 | `foreach ($items as $item)` |

**Recommendation:** Extract to data providers or inline values.

## Action Items

1. **High Priority** — Refactor tests with >5 mocks
2. **Medium Priority** — Inline fixture data

Severity Matrix

Severity	Smells	Impact
High	Logic in Test, Mock Overuse, Test Interdependence, Fragile Test, Mocking Final/VO, Testing Private	Unreliable results, design problems
Medium	Mystery Guest, Eager Test, Slow Test, Conditional Logic, Duplication	Hard to understand/maintain
Low	Obscure Test, Hard-Coded Data	Documentation/readability

Related Skills

Smell	Fix With
Mock Overuse	`create-mock-repository`
Mystery Guest	`create-test-builder`
Test Duplication	`create-test-builder`

References

references/smell-catalog.md — Full smell descriptions with code examples
references/refactoring-patterns.md — Refactoring patterns for testability