refactor: Replace string comparison with SymbolEqualityComparer in analyzers

[thomhurst]

Summary

• Changes SymbolExtensions.InheritsFrom from string-based comparison to proper Roslyn symbol comparison using SymbolEqualityComparer
• Simplifies complex nested conditionals in LoggerInConstructorAnalyzer with early returns and helper methods
• Improves maintainability and correctness of analyzer code

Fixes #1606, #1599

Test plan

• Build passes
• All analyzer tests pass

🤖 Generated with Claude Code

[thomhurst]

Summary

Refactors analyzer code to use proper Roslyn symbol comparison (SymbolEqualityComparer) instead of string-based comparison, improving correctness and maintainability.

Critical Issues

None found ✅

Suggestions

Code Quality Improvements

SymbolExtensions.cs:15 - Consider caching GetTypeByMetadataName results
The InheritsFrom(ITypeSymbol?, Compilation, string) method calls compilation.GetTypeByMetadataName() on every invocation. For performance-critical analyzer scenarios, consider:

• Passing the resolved INamedTypeSymbol directly where possible (like the overload on line 33)
• Or adding inline documentation noting this is intentional for simplicity

ConflictingDependsOnAttributeAnalyzer.cs:103 and SymbolExtensions.cs:184 - Code duplication
The IsDependsOnAttributeType method is duplicated in two locations with identical logic. Consider:

• Moving it to SymbolExtensions and making it internal
• The one in SymbolExtensions (line 184) is already private in the right location - just make it internal and remove the duplicate

LoggerInConstructorAnalyzer.cs:26 - Consider using ImmutableHashSet
Since LoggingTypeMetadataNames is used for membership checks in IsAnyType, an ImmutableHashSet would be more semantically appropriate than ImmutableArray (though the performance difference is negligible for 4 items).

SymbolExtensions.cs:46 - Minor: Early exit opportunity
In InheritsFrom(ITypeSymbol?, INamedTypeSymbol?), you could check SymbolEqualityComparer.Default.Equals(typeSymbol.OriginalDefinition, targetType.OriginalDefinition) before the loop to handle the case where the type equals the target directly.

Previous Review Status

No previous comments found.

Verdict

✅ APPROVE - No critical issues

This is a solid refactoring that improves code quality by using proper Roslyn symbol comparison semantics. The suggested improvements are minor and optional.