Merge pull request #276 from CommunityToolkit/dev/fix-generators-in-root-namespace

Fix source generators for types in global namespace

Author: Sergio0694

CommunityToolkit.Mvvm.SourceGenerators/Extensions/INamedTypeSymbolExtensions.cs

@@ -27,8 +27,10 @@ static StringBuilder BuildFrom(ISymbol? symbol, StringBuilder builder)
                 INamespaceSymbol ns when ns.IsGlobalNamespace => builder,
                 INamespaceSymbol ns when ns.ContainingNamespace is { IsGlobalNamespace: false }
                     => BuildFrom(ns.ContainingNamespace, builder.Insert(0, $".{ns.MetadataName}")),
-                ITypeSymbol ts when ts.ContainingType is ISymbol pt => BuildFrom(pt, builder.Insert(0, $"+{ts.MetadataName}")),
-                ITypeSymbol ts when ts.ContainingNamespace is ISymbol pn => BuildFrom(pn, builder.Insert(0, $".{ts.MetadataName}")),
+                ITypeSymbol ts when ts.ContainingType is ISymbol pt
+                    => BuildFrom(pt, builder.Insert(0, $"+{ts.MetadataName}")),
+                ITypeSymbol ts when ts.ContainingNamespace is ISymbol pn and not INamespaceSymbol { IsGlobalNamespace: true }
+                    => BuildFrom(pn, builder.Insert(0, $".{ts.MetadataName}")),
                 ISymbol => BuildFrom(symbol.ContainingSymbol, builder.Insert(0, symbol.MetadataName)),
                 _ => builder
             };

CommunityToolkit.Mvvm.SourceGenerators/Models/HierarchyInfo.Syntax.cs

@@ -54,23 +54,42 @@ public CompilationUnitSyntax GetCompilationUnit(
                 .AddMembers(typeDeclarationSyntax);
         }
 
-        // Create the compilation unit with disabled warnings, target namespace and generated type.
+        // Prepare the leading trivia for the generated compilation unit.
         // This will produce code as follows:
         //
         // <auto-generated/>
         // #pragma warning disable
         // #nullable enable
+        SyntaxTriviaList syntaxTriviaList = TriviaList(
+            Comment("// <auto-generated/>"),
+            Trivia(PragmaWarningDirectiveTrivia(Token(SyntaxKind.DisableKeyword), true)),
+            Trivia(NullableDirectiveTrivia(Token(SyntaxKind.EnableKeyword), true)));
+
+        if (Namespace is "")
+        {
+            // If there is no namespace, attach the pragma directly to the declared type,
+            // and skip the namespace declaration. This will produce code as follows:
+            //
+            // <SYNTAX_TRIVIA>
+            // <TYPE_HIERARCHY>
+            return
+                CompilationUnit()
+                .AddMembers(typeDeclarationSyntax.WithLeadingTrivia(syntaxTriviaList))
+                .NormalizeWhitespace();
+        }
+
+        // Create the compilation unit with disabled warnings, target namespace and generated type.
+        // This will produce code as follows:
+        //
+        // <SYNTAX_TRIVIA>
         // namespace <NAMESPACE>
         // {
         //     <TYPE_HIERARCHY>
         // }
         return
             CompilationUnit().AddMembers(
             NamespaceDeclaration(IdentifierName(Namespace))
-            .WithLeadingTrivia(TriviaList(
-                Comment("// <auto-generated/>"),
-                Trivia(PragmaWarningDirectiveTrivia(Token(SyntaxKind.DisableKeyword), true)),
-                Trivia(NullableDirectiveTrivia(Token(SyntaxKind.EnableKeyword), true))))
+            .WithLeadingTrivia(syntaxTriviaList)
             .AddMembers(typeDeclarationSyntax))
             .NormalizeWhitespace();
     }

tests/CommunityToolkit.Mvvm.UnitTests/Test_ObservablePropertyAttribute.RootNamespace.cs

@@ -0,0 +1,12 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using CommunityToolkit.Mvvm.ComponentModel;
+
+// Test viewmodel for https://github.com/CommunityToolkit/dotnet/issues/271
+internal partial class ModelWithObservablePropertyInRootNamespace : ObservableObject
+{
+    [ObservableProperty]
+    private float number;
+}

tests/CommunityToolkit.Mvvm.UnitTests/Test_ObservablePropertyAttribute.cs

@@ -731,6 +731,22 @@ public void Test_ObservableProperty_ForwardsSpecialCasesDataAnnotationAttributes
         Assert.IsTrue(scaffoldColumnAttribute!.Scaffold);
     }
 
+    // See https://github.com/CommunityToolkit/dotnet/issues/271
+    [TestMethod]
+    public void Test_ObservableProperty_ModelWithObservablePropertyInRootNamespace()
+    {
+        ModelWithObservablePropertyInRootNamespace model = new();
+
+        List<string?> propertyNames = new();
+
+        model.PropertyChanged += (s, e) => propertyNames.Add(e.PropertyName);
+
+        model.Number = 3.14f;
+
+        // We mostly just need to verify this class compiles fine with the right generated code
+        CollectionAssert.AreEqual(propertyNames, new[] { nameof(model.Number) });
+    }
+
     public abstract partial class BaseViewModel : ObservableObject
     {
         public string? Content { get; set; }