Clarify the MA0095 comment about the Equals(object) lookup - #1518
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The comment claimed the entire type hierarchy was checked for an Equals(object) override, but the code only looks at the members declared by the type itself. The behavior is intentional and documented: a type that introduces new equality semantics through IEquatable<T> must override Equals(object) itself, otherwise the inherited override would disagree with them. Only the comment was wrong, so it now describes what the code does and why.
This was referenced Sep 12, 2026
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This was referenced Sep 26, 2026
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What changed
The comment above the MA0095 check in
EqualityShouldBeCorrectlyImplementedAnalyzersaid:but the code calls
symbol.GetMembers(), which only returns the members declared by the type itself — a base-type override is not visible there. The comment now states what the code does and why.Why
The behavior is correct and intentional: a type that introduces new equality semantics through
IEquatable<T>must overrideEquals(object)itself, otherwiseobject.Equals(inherited from the base) andIEquatable<T>.Equalswould disagree. This exact shape is listed as non-compliant in docs/Rules/MA0095.md. Only the comment was misleading — it suggested a bug where there is none, and could prompt a "fix" that breaks the rule.Notes for reviewers
InheritedIEquatable_WithDirectImplementationToo_ShouldTriggeralready locks in the scenario (base overridesEquals(object), derived implementsIEquatable<Derived>→ MA0095 reported).Meziantou.Analyzer.roslyn5.9builds with 0 warnings, the 46EqualityShouldBeCorrectlyImplementedAnalyzerTeststests pass, anddotnet run --project src/DocumentationGeneratorexits 0 with no markdown changes.