Merge pull request #1026 from CommunityToolkit/dev/fix-body-expressions

Handle semi-auto properties with expression bodies

Author: Sergio0694

src/CommunityToolkit.Mvvm.SourceGenerators/Diagnostics/Analyzers/UseObservablePropertyOnSemiAutoPropertyAnalyzer.cs

@@ -249,8 +249,12 @@ public override void Initialize(AnalysisContext context)
                     }
 
                     // Check that either of them is a semicolon token 'get;' accessor (it can be in either position)
-                    if (firstAccessor.IsKind(SyntaxKind.GetAccessorDeclaration) && firstAccessor.SemicolonToken.IsKind(SyntaxKind.SemicolonToken) ||
-                        secondAccessor.IsKind(SyntaxKind.GetAccessorDeclaration) && secondAccessor.SemicolonToken.IsKind(SyntaxKind.SemicolonToken))
+                    if (firstAccessor.IsKind(SyntaxKind.GetAccessorDeclaration) &&
+                        firstAccessor.SemicolonToken.IsKind(SyntaxKind.SemicolonToken) &&
+                        firstAccessor.ExpressionBody is null ||
+                        secondAccessor.IsKind(SyntaxKind.GetAccessorDeclaration) &&
+                        secondAccessor.SemicolonToken.IsKind(SyntaxKind.SemicolonToken) &&
+                        secondAccessor.ExpressionBody is null)
                     {
                         validFlags[0] = true;
                     }

tests/CommunityToolkit.Mvvm.SourceGenerators.Roslyn4120.UnitTests/Test_SourceGeneratorsDiagnostics.cs

@@ -1403,6 +1403,27 @@ public string Name
         await CSharpAnalyzerWithLanguageVersionTest<UseObservablePropertyOnSemiAutoPropertyAnalyzer>.VerifyAnalyzerAsync(source, LanguageVersion.Preview);
     }
 
+    [TestMethod]
+    public async Task UseObservablePropertyOnSemiAutoPropertyAnalyzer_GetAccessorWithExpressionBody_DoesNotWarn()
+    {
+        const string source = """
+            using CommunityToolkit.Mvvm.ComponentModel;
+
+            namespace MyApp;
+
+            public partial class SampleViewModel : ObservableObject
+            {
+                public string Name
+                {
+                    get => "Hello world";
+                    set => SetProperty(ref field, value);
+                }
+            }
+            """;
+
+        await CSharpAnalyzerWithLanguageVersionTest<UseObservablePropertyOnSemiAutoPropertyAnalyzer>.VerifyAnalyzerAsync(source, LanguageVersion.Preview);
+    }
+
     [TestMethod]
     public async Task UseObservablePropertyOnSemiAutoPropertyAnalyzer_ValidProperty_Warns()
     {