Fix IDE0028: Suppress diagnostic in CollectionBuilder methods to prevent infinite recursion #81004
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- Added virtual method ShouldSuppressDiagnostic to base analyzer - Implemented CollectionBuilder detection in C# analyzer - Detects when we're inside a CollectionBuilder method to avoid infinite recursion - Added tests to verify the fix works correctly Co-authored-by: CyrusNajmabadi <[email protected]>
Use OriginalDefinition to check attributes on generic types and compare builder types correctly Co-authored-by: CyrusNajmabadi <[email protected]>
- Use IsCollectionBuilderAttribute() helper method instead of manual namespace checking - Use NewKeyword.SpanStart for more precise position when getting enclosing symbol - Add null check for AttributeClass before calling extension method Co-authored-by: CyrusNajmabadi <[email protected]>
Explain that CollectionBuilderAttribute has exactly 2 constructor parameters Co-authored-by: CyrusNajmabadi <[email protected]>
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[WIP] Fix IDE0028 warning for collection initialization
Fix IDE0028: Suppress diagnostic in CollectionBuilder methods to prevent infinite recursion
Nov 3, 2025
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CyrusNajmabadi
November 3, 2025 22:19
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| var builderTypeArg = collectionBuilderAttribute.ConstructorArguments[0]; | ||
| var methodNameArg = collectionBuilderAttribute.ConstructorArguments[1]; | ||
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| if (builderTypeArg.Kind != TypedConstantKind.Type || | ||
| builderTypeArg.Value is not INamedTypeSymbol builderType || | ||
| methodNameArg.Kind != TypedConstantKind.Primitive || | ||
| methodNameArg.Value is not string methodName) | ||
| { | ||
| return false; | ||
| } |
| ObjectCreationExpressionSyntax objCreation => objCreation.NewKeyword.SpanStart, | ||
| ImplicitObjectCreationExpressionSyntax implicitObjCreation => implicitObjCreation.NewKeyword.SpanStart, | ||
| _ => objectCreationExpression.SpanStart | ||
| }; |
| ReferenceAssemblies = ReferenceAssemblies.Net.Net80, | ||
| }.RunAsync(); | ||
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| [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/74268")] |
Replace separate extraction and validation with a single pattern match expression Co-authored-by: CyrusNajmabadi <[email protected]>
- Use objectCreationExpression.SpanStart directly instead of switch statement - Update WorkItem references from issue #74268 to #70099 Co-authored-by: CyrusNajmabadi <[email protected]>
dibarbet
approved these changes
Nov 3, 2025
...ore/Analyzers/UseCollectionInitializer/AbstractUseCollectionInitializerDiagnosticAnalyzer.cs
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| namespace System.Runtime.CompilerServices | ||
| { | ||
| [AttributeUsage(AttributeTargets.All, Inherited = false, AllowMultiple = false)] | ||
| public sealed class CollectionBuilderAttribute : Attribute |
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is the definition necessary? e.g. it isn't included in the standard testworkspace references?
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technically not in the refeences. but we have a string constant for it. updating.
…UseCollectionInitializerDiagnosticAnalyzer.cs Co-authored-by: David Barbet <[email protected]>
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Fix for IDE0028 with CollectionBuilder Methods ✅
This PR fixes issue #70099 where IDE0028 (Collection initialization can be simplified) incorrectly suggests using collection expressions inside CollectionBuilder methods, which would cause infinite recursion.
Problem
When implementing a CollectionBuilder method, the analyzer would suggest converting:
To:
This causes infinite recursion because the collection expression
[.. items]calls the same CollectionBuilder method.Solution
Added detection logic to suppress the diagnostic when:
Implementation
ShouldSuppressDiagnosticmethodIsCollectionBuilderAttribute()helper for type checkingOriginalDefinitioncomparison for generic typesFiles Changed
src/Analyzers/Core/Analyzers/UseCollectionInitializer/AbstractUseCollectionInitializerDiagnosticAnalyzer.cssrc/Analyzers/CSharp/Analyzers/UseCollectionInitializer/CSharpUseCollectionInitializerDiagnosticAnalyzer.cssrc/Analyzers/CSharp/Tests/UseCollectionInitializer/UseCollectionInitializerTests_CollectionExpression.csCommits
All changes follow Roslyn coding conventions and include comprehensive tests.
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