SOLID Violations Analyzer

Overview

This skill analyzes PHP codebases for SOLID principle violations and generates detailed reports with severity levels and remediation recommendations.

Analysis Workflow

Step 1: Scope Identification

Determine analysis scope from user input or detect automatically:

# Detect project structure
ls -la src/

# Identify key directories
find . -type d -name "Domain" -o -name "Application" -o -name "Infrastructure"

Step 2: Run Detection Patterns

Execute detection patterns for each SOLID principle.

SRP (Single Responsibility) Detection

God Class Detection

# Find large classes (>500 lines)
find . -name "*.php" -path "*/src/*" -exec wc -l {} \; | awk '$1 > 500 {print "CRITICAL: " $0}'

# Find classes with many methods
for file in $(find . -name "*.php" -path "*/src/*"); do
  count=$(grep -c "public function" "$file" 2>/dev/null || echo 0)
  if [ "$count" -gt 15 ]; then
    echo "WARNING: $file has $count public methods"
  fi
done

# Classes with problematic names
grep -rn "class.*Manager\|class.*Handler\|class.*Helper\|class.*Util" --include="*.php" src/

High Dependency Count

# Count constructor dependencies
grep -rn "__construct" --include="*.php" -A 20 src/ | \
  grep -E "private|readonly" | \
  awk -F: '{files[$1]++} END {for(f in files) if(files[f]>7) print "WARNING: " f " has " files[f] " dependencies"}'

Multiple Responsibility Indicators

# Classes with "And" in name
grep -rn "class\s\+\w*And\w*" --include="*.php" src/

# Check for mixed concerns
grep -rn "class.*Service" --include="*.php" src/ -l | while read file; do
  if grep -q "Repository\|Mailer\|Logger" "$file"; then
    echo "INFO: $file may have mixed concerns"
  fi
done

OCP (Open/Closed) Detection

Type Switch Detection

# Switch on type property
grep -rn "switch.*->type\|match.*->type\|match.*::class" --include="*.php" src/

# instanceof chains
grep -rn "if.*instanceof\|elseif.*instanceof" --include="*.php" src/

# Type-based conditionals
grep -rn "if.*getType\(\)\s*===\|if.*->type\s*===" --include="*.php" src/

# Hardcoded type maps
grep -rn "\[.*::class\s*=>" --include="*.php" src/

Extension Indicators

# Classes that need frequent modification (check git history if available)
git log --since="3 months ago" --name-only --pretty=format: -- "*.php" | \
  sort | uniq -c | sort -rn | head -20

LSP (Liskov Substitution) Detection

Contract Violations

# NotImplementedException throws
grep -rn "throw.*NotImplemented\|throw.*NotSupported\|throw.*UnsupportedOperation" --include="*.php" src/

# Empty method overrides
grep -rn "public function.*\{[\s]*\}" --include="*.php" src/

# Parent type checks in child classes
grep -rn "if.*parent::\|parent::.*?:" --include="*.php" src/

Precondition/Postcondition Issues

# Additional validation in overrides
grep -rn "function.*override" --include="*.php" -A 10 src/ | grep "if.*throw"

# Return null where parent might not
grep -rn "return\s*null;" --include="*.php" src/

ISP (Interface Segregation) Detection

Fat Interface Detection

# Count methods in interfaces
for file in $(find . -name "*.php" -path "*/src/*" -exec grep -l "^interface" {} \;); do
  count=$(grep -c "public function" "$file" 2>/dev/null || echo 0)
  if [ "$count" -gt 5 ]; then
    echo "WARNING: $file interface has $count methods"
  fi
  if [ "$count" -gt 8 ]; then
    echo "CRITICAL: $file interface has $count methods - consider splitting"
  fi
done

Unused Interface Methods

# Find "// TODO" or "// not implemented" in interface implementations
grep -rn "//\s*TODO\|//\s*not implemented\|//\s*unused" --include="*.php" src/

# Empty implementations
grep -rn "function.*\{[\s]*return;\s*\}" --include="*.php" src/

Generic Interface Names

# Overly generic interface names
grep -rn "interface\s\+\(Service\|Manager\|Handler\)\s*$" --include="*.php" src/

DIP (Dependency Inversion) Detection

Direct Instantiation

# New in methods (excluding exceptions, DateTime, stdClass)
grep -rn "new\s\+[A-Z]" --include="*.php" src/ | \
  grep -v "Exception\|DateTime\|stdClass\|DateTimeImmutable\|ArrayObject\|SplQueue"

# Static method calls to concrete classes
grep -rn "[A-Z][a-z]*::[a-z]" --include="*.php" src/ | \
  grep -v "self::\|static::\|parent::\|Uuid::\|Money::"

Concrete Type Hints

# Constructor with concrete types (not interfaces)
grep -rn "__construct" --include="*.php" -A 15 src/ | \
  grep -E "(private|readonly)\s+[A-Z][a-z]*[A-Z][a-z]*\s+\\\$" | \
  grep -v "Interface\|Abstract\|Contract"

Service Locator Anti-pattern

# Container/locator usage
grep -rn "container->get\|app()->make\|\\\$this->get(" --include="*.php" src/

Report Generation

Analysis Output Format

# SOLID Violations Report

## Summary

| Principle | Critical | Warning | Info |
|-----------|----------|---------|------|
| SRP | X | X | X |
| OCP | X | X | X |
| LSP | X | X | X |
| ISP | X | X | X |
| DIP | X | X | X |

## Critical Violations

### SRP-001: God Class
- **File:** `src/Service/UserManager.php`
- **Lines:** 847
- **Issue:** Class exceeds 500 lines with 23 public methods
- **Recommendation:** Extract into focused classes
- **Skills:** `create-use-case`, `create-domain-service`

### OCP-001: Type Switch
- **File:** `src/Payment/PaymentProcessor.php:45`
- **Issue:** Switch on payment type requires modification for new types
- **Recommendation:** Apply Strategy pattern
- **Skills:** `create-strategy`

## Warning Violations

### ISP-001: Fat Interface
- **File:** `src/Repository/UserRepository.php`
- **Methods:** 12
- **Issue:** Interface too large, clients forced to depend on unused methods
- **Recommendation:** Segregate into UserReader, UserWriter, UserStats

## Remediation Priority

1. **Immediate:** God classes blocking testing
2. **High:** Type switches preventing extension
3. **Medium:** Fat interfaces causing coupling
4. **Low:** Minor DIP violations

Severity Classification

Severity	Criteria	Action
CRITICAL	>500 LOC, >10 deps, NotImplementedException	Immediate refactoring
WARNING	300-500 LOC, 7-10 deps, type switches	Plan refactoring
INFO	200-300 LOC, minor issues	Monitor in next iteration

Remediation Skills

Violation	Recommended Skill
God Class	create-use-case
Type Switch	create-strategy
No Interface	create-repository
Domain Logic	create-domain-service
Value Extraction	create-value-object
Factory Missing	create-factory
Decorator Need	create-decorator

Quick Analysis Commands

# Full analysis
echo "=== SRP ===" && \
find . -name "*.php" -path "*/src/*" -exec wc -l {} \; | awk '$1 > 400' && \
echo "=== OCP ===" && \
grep -rn "switch.*type\|match.*::class" --include="*.php" src/ && \
echo "=== LSP ===" && \
grep -rn "NotImplemented\|NotSupported" --include="*.php" src/ && \
echo "=== ISP ===" && \
for f in $(find . -name "*.php" -exec grep -l "^interface" {} \;); do \
  c=$(grep -c "public function" "$f"); [ $c -gt 5 ] && echo "$f: $c methods"; \
done && \
echo "=== DIP ===" && \
grep -rn "new\s\+[A-Z]" --include="*.php" src/ | grep -v "Exception\|DateTime" | head -20

Integration with solid-knowledge

This analyzer uses detection patterns from solid-knowledge. For detailed principle explanations and patterns, refer to:

• solid-knowledge/references/srp-patterns.md
• solid-knowledge/references/ocp-patterns.md
• solid-knowledge/references/lsp-patterns.md
• solid-knowledge/references/isp-patterns.md
• solid-knowledge/references/dip-patterns.md
• solid-knowledge/references/antipatterns.md

Report Template

See assets/report-template.md for the full report format.

When This Is Acceptable

• Doctrine entities — Entities may appear to violate SRP due to persistence concerns mixed with domain logic (framework requirement)
• DTOs/Value Objects — Data classes with many properties don't violate SRP (single responsibility = data transfer)
• Framework controllers — Slim controllers with inject+validate+delegate are acceptable

False Positive Indicators

• Class is a DTO, Value Object, or Request/Response object
• Class is a Doctrine entity with only getters/setters + domain methods
• Apparent SRP violation is actually framework convention