PropertyChangedCallback

Author: JohanLarsson

WpfAnalyzers/Analyzers/PropertyMetadataAnalyzer.cs

@@ -38,7 +38,7 @@ context.Node is ObjectCreationExpressionSyntax objectCreation &&
             if (propertyMetadata.FindRegisteredName(context.SemanticModel, context.CancellationToken) is { Value: { } registeredName })
             {
                 if (propertyMetadata.PropertyChangedArgument is { } propertyChangeArgument &&
-                    Callback.Match(propertyChangeArgument, KnownSymbols.PropertyChangedCallback, context.SemanticModel, context.CancellationToken) is { Identifier: { } onPropertyChangedNode, Target: { } onPropertyChanged })
+                    PropertyChangedCallback.Match(propertyChangeArgument, context.SemanticModel, context.CancellationToken) is { Identifier: { } onPropertyChangedNode, Target: { } onPropertyChanged })
                 {
                     if (TypeSymbolComparer.Equal(onPropertyChanged.ContainingType, context.ContainingSymbol.ContainingType) &&
                         !onPropertyChanged.Name.IsParts("On", registeredName, "Changed") &&

WpfAnalyzers/Helpers/PropertyChangedCallback.cs

@@ -0,0 +1,27 @@
+namespace WpfAnalyzers;
+
+using System.Threading;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+
+internal readonly struct PropertyChangedCallback
+{
+    internal readonly IdentifierNameSyntax Identifier;
+    internal readonly IMethodSymbol Target;
+
+    internal PropertyChangedCallback(IdentifierNameSyntax identifier, IMethodSymbol target)
+    {
+        this.Identifier = identifier;
+        this.Target = target;
+    }
+
+    internal static PropertyChangedCallback? Match(ArgumentSyntax callback, SemanticModel semanticModel, CancellationToken cancellationToken)
+    {
+        if (Callback.Match(callback, KnownSymbols.PropertyChangedCallback, semanticModel, cancellationToken) is { } match)
+        {
+            return new PropertyChangedCallback(match.Identifier, match.Target);
+        }
+
+        return null;
+    }
+}