Add Attached Bindable Property support

src/CommunityToolkit.Maui.SourceGenerators.Internal.UnitTests/AttachedBindablePropertySourceGeneratorTests/BaseAttachedBindablePropertyAttributeSourceGeneratorTest.cs

@@ -0,0 +1,95 @@
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp.Testing;
+using Microsoft.CodeAnalysis.Testing;
+using System.IO;
+using System.Collections.Generic;
+using Xunit;
+
+namespace CommunityToolkit.Maui.SourceGenerators.Internal.UnitTests.AttachedBindablePropertySourceGeneratorTests;
+
+public class BaseAttachedBindablePropertyAttributeSourceGeneratorTest : CommunityToolkit.Maui.SourceGenerators.Internal.UnitTests.BaseTest
+{
+    protected const string defaultTestClassName = "TestView";
+    protected const string defaultTestNamespace = "TestNamespace";
+
+    protected const string expectedAttribute =
+        /* language=C#-test */
+        //lang=csharp
+        $$"""
+      // <auto-generated>
+      // See: CommunityToolkit.Maui.SourceGenerators.Internal.AttachedBindablePropertySourceGenerator
+
+      #pragma warning disable
+      #nullable enable
+      namespace CommunityToolkit.Maui;
+
+      [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+      [global::System.AttributeUsage(global::System.AttributeTargets.Property, AllowMultiple = false, Inherited = false)]
+      [global::System.Diagnostics.CodeAnalysis.Experimental("{{AttachedBindablePropertySourceGenerator.BindablePropertyAttributeExperimentalDiagnosticId}}")]
+      sealed partial class AttachedBindablePropertyAttribute : global::System.Attribute
+      {
+          public string? PropertyName { get; }
+          public global::System.Type? DeclaringType { get; set; }
+          public global::Microsoft.Maui.Controls.BindingMode DefaultBindingMode { get; set; }
+          public string ValidateValueMethodName { get; set; } = string.Empty;
+          public string PropertyChangedMethodName { get; set; } = string.Empty;
+          public string PropertyChangingMethodName { get; set; } = string.Empty;
+          public string CoerceValueMethodName { get; set; } = string.Empty;
+          public string DefaultValueCreatorMethodName { get; set; } = string.Empty;
+      }
+      """;
+
+    protected static async Task VerifyAttachedSourceGeneratorAsync(string source, string expectedGenerated)
+    {
+        const string sourceGeneratorNamespace = "CommunityToolkit.Maui.SourceGenerators.Internal";
+        const string attachedBindablePropertyAttributeGeneratedFileName = "AttachedBindablePropertyAttribute.g.cs";
+        var attachedSourceGeneratorFullName = typeof(AttachedBindablePropertySourceGenerator).FullName ?? throw new InvalidOperationException("Source Generator Type Path cannot be null");
+
+        var test = new AttachedBindablePropertyTest
+        {
+#if NET10_0
+            ReferenceAssemblies = Microsoft.CodeAnalysis.Testing.ReferenceAssemblies.Net.Net100,
+#else
+#error ReferenceAssemblies must be updated to current version of .NET
+#endif
+            TestState =
+            {
+                Sources = { source },
+
+                AdditionalReferences =
+                {
+                    MetadataReference.CreateFromFile(typeof(Microsoft.Maui.Controls.BindableObject).Assembly.Location),
+                    MetadataReference.CreateFromFile(typeof(Microsoft.Maui.Controls.BindableProperty).Assembly.Location),
+                    MetadataReference.CreateFromFile(typeof(Microsoft.Maui.Controls.BindingMode).Assembly.Location)
+                }
+            }
+        };
+
+        var expectedAttributeText = Microsoft.CodeAnalysis.Text.SourceText.From(expectedAttribute, System.Text.Encoding.UTF8);
+        // Use the same prefix the test harness uses so the expected generated file path matches actual
+        var attributeFilePath = Path.Combine(sourceGeneratorNamespace, attachedSourceGeneratorFullName, attachedBindablePropertyAttributeGeneratedFileName);
+        test.TestState.GeneratedSources.Add((attributeFilePath, expectedAttributeText));
+
+        if (!string.IsNullOrEmpty(expectedGenerated))
+        {
+            var expectedGeneratedText = Microsoft.CodeAnalysis.Text.SourceText.From(expectedGenerated, System.Text.Encoding.UTF8);
+            var generatedFilePath = Path.Combine(sourceGeneratorNamespace, attachedSourceGeneratorFullName, $"{defaultTestClassName}.g.cs");
+            test.TestState.GeneratedSources.Add((generatedFilePath, expectedGeneratedText));
+        }
+
+        await test.RunAsync(TestContext.Current.CancellationToken);
+    }
+
+    sealed class AttachedBindablePropertyTest : CSharpSourceGeneratorTest<AttachedBindablePropertySourceGenerator, DefaultVerifier>
+    {
+        protected override CompilationOptions CreateCompilationOptions()
+        {
+            var compilationOptions = base.CreateCompilationOptions();
+
+            return compilationOptions.WithSpecificDiagnosticOptions(new Dictionary<string, ReportDiagnostic>
+            {
+                { AttachedBindablePropertySourceGenerator.BindablePropertyAttributeExperimentalDiagnosticId, ReportDiagnostic.Warn }
+            });
+        }
+    }
+}

src/CommunityToolkit.Maui.SourceGenerators.Internal.UnitTests/AttachedBindablePropertySourceGeneratorTests/CommonUsageTests.cs

@@ -0,0 +1,202 @@
+using System.Threading.Tasks;
+using Xunit;
+
+namespace CommunityToolkit.Maui.SourceGenerators.Internal.UnitTests.AttachedBindablePropertySourceGeneratorTests;
+
+public class CommonUsageTests : BaseAttachedBindablePropertyAttributeSourceGeneratorTest
+{
+	[Fact]
+	public async Task GenerateAttachedBindableProperty_SimpleExample_GeneratesCorrectCode()
+	{
+		const string source =
+			/* language=C#-test */
+			//lang=csharp
+			$$"""
+            using CommunityToolkit.Maui;
+            using Microsoft.Maui.Controls;
+
+            namespace {{defaultTestNamespace}};
+
+            public partial class {{defaultTestClassName}} : View
+            {
+                [AttachedBindableProperty]
+                public partial string Text { get; set; }
+            }
+            """;
+
+		const string expectedGenerated =
+			/* language=C#-test */
+			//lang=csharp
+			$$"""
+            // <auto-generated>
+            // See: CommunityToolkit.Maui.SourceGenerators.Internal.AttachedBindablePropertySourceGenerator
+            #pragma warning disable
+            #nullable enable
+            using global::Microsoft.Maui.Controls;
+
+            namespace {{defaultTestNamespace}};
+            public partial class {{defaultTestClassName}}
+            {
+                /// <summary>
+                /// Backing BindableProperty for the <see cref = "Text"/> property.
+                /// </summary>
+                public static readonly global::Microsoft.Maui.Controls.BindableProperty TextProperty = global::Microsoft.Maui.Controls.BindableProperty.CreateAttached("Text", typeof(string), typeof({{defaultTestNamespace}}.{{defaultTestClassName}}), null, Microsoft.Maui.Controls.BindingMode.OneWay, null, null, null, null, null);
+                public partial string Text { get => (string)GetValue(TextProperty); set => SetValue(TextProperty, value); }
+
+                public static string GetText(BindableObject view) => (string)view.GetValue(TextProperty);
+                public static void SetText(BindableObject view, string value) => view.SetValue(TextProperty, value);
+            }
+            """;
+
+		await VerifyAttachedSourceGeneratorAsync(source, expectedGenerated);
+	}
+
+	[Fact]
+	public async Task GenerateAttachedBindableProperty_WithNewKeyword_GeneratesCorrectCode()
+	{
+		const string source =
+			/* language=C#-test */
+			//lang=csharp
+			$$"""
+            using CommunityToolkit.Maui;
+            using Microsoft.Maui.Controls;
+
+            namespace {{defaultTestNamespace}};
+
+            public partial class {{defaultTestClassName}} : View
+            {
+                [AttachedBindableProperty]
+                public new partial string Text { get; set; }
+            }
+            """;
+
+		const string expectedGenerated =
+			/* language=C#-test */
+			//lang=csharp
+			$$"""
+            // <auto-generated>
+            // See: CommunityToolkit.Maui.SourceGenerators.Internal.AttachedBindablePropertySourceGenerator
+            #pragma warning disable
+            #nullable enable
+            using global::Microsoft.Maui.Controls;
+
+            namespace {{defaultTestNamespace}};
+            public partial class {{defaultTestClassName}}
+            {
+                /// <summary>
+                /// Backing BindableProperty for the <see cref = "Text"/> property.
+                /// </summary>
+                public new static readonly global::Microsoft.Maui.Controls.BindableProperty TextProperty = global::Microsoft.Maui.Controls.BindableProperty.CreateAttached("Text", typeof(string), typeof({{defaultTestNamespace}}.{{defaultTestClassName}}), null, Microsoft.Maui.Controls.BindingMode.OneWay, null, null, null, null, null);
+                public new partial string Text { get => (string)GetValue(TextProperty); set => SetValue(TextProperty, value); }
+
+                public static string GetText(BindableObject view) => (string)view.GetValue(TextProperty);
+                public static void SetText(BindableObject view, string value) => view.SetValue(TextProperty, value);
+            }
+            """;
+
+		await VerifyAttachedSourceGeneratorAsync(source, expectedGenerated);
+	}
+
+	[Fact]
+	public async Task GenerateAttachedBindableProperty_NullableReferenceType_GeneratesCorrectCode()
+	{
+		const string source =
+			/* language=C#-test */
+			//lang=csharp
+			$$"""
+            using CommunityToolkit.Maui;
+            using Microsoft.Maui.Controls;
+
+            namespace {{defaultTestNamespace}};
+
+            public partial class {{defaultTestClassName}} : View
+            {
+                [AttachedBindableProperty]
+                public partial string? Text { get; set; }
+            }
+            """;
+
+		const string expectedGenerated =
+			/* language=C#-test */
+			//lang=csharp
+			$$"""
+            // <auto-generated>
+            // See: CommunityToolkit.Maui.SourceGenerators.Internal.AttachedBindablePropertySourceGenerator
+            #pragma warning disable
+            #nullable enable
+            using global::Microsoft.Maui.Controls;
+
+            namespace {{defaultTestNamespace}};
+            public partial class {{defaultTestClassName}}
+            {
+                /// <summary>
+                /// Backing BindableProperty for the <see cref = "Text"/> property.
+                /// </summary>
+                public static readonly global::Microsoft.Maui.Controls.BindableProperty TextProperty = global::Microsoft.Maui.Controls.BindableProperty.CreateAttached("Text", typeof(string), typeof({{defaultTestNamespace}}.{{defaultTestClassName}}), null, Microsoft.Maui.Controls.BindingMode.OneWay, null, null, null, null, null);
+                public partial string? Text { get => (string)GetValue(TextProperty); set => SetValue(TextProperty, value); }
+
+                public static string? GetText(BindableObject view) => (string)view.GetValue(TextProperty);
+                public static void SetText(BindableObject view, string? value) => view.SetValue(TextProperty, value);
+            }
+            """;
+
+		await VerifyAttachedSourceGeneratorAsync(source, expectedGenerated);
+	}
+
+	[Fact]
+	public async Task GenerateAttachedBindableProperty_MultipleProperties_GeneratesCorrectCode()
+	{
+		const string source =
+			/* language=C#-test */
+			//lang=csharp
+			$$"""
+        using CommunityToolkit.Maui;
+        using Microsoft.Maui.Controls;
+
+        namespace {{defaultTestNamespace}};
+
+        public partial class {{defaultTestClassName}} : View
+        {
+            [AttachedBindableProperty]
+            public partial string Text { get; set; }
+
+            [AttachedBindableProperty]
+            public partial int Number { get; set; }
+        }
+        """;
+
+		const string expectedGenerated =
+			/* language=C#-test */
+			//lang=csharp
+			$$"""
+        // <auto-generated>
+        // See: CommunityToolkit.Maui.SourceGenerators.Internal.AttachedBindablePropertySourceGenerator
+        #pragma warning disable
+        #nullable enable
+        using global::Microsoft.Maui.Controls;
+
+        namespace {{defaultTestNamespace}};
+        public partial class {{defaultTestClassName}}
+        {
+            /// <summary>
+            /// Backing BindableProperty for the <see cref = "Text"/> property.
+            /// </summary>
+            public static readonly global::Microsoft.Maui.Controls.BindableProperty TextProperty = global::Microsoft.Maui.Controls.BindableProperty.CreateAttached("Text", typeof(string), typeof({{defaultTestNamespace}}.{{defaultTestClassName}}), null, Microsoft.Maui.Controls.BindingMode.OneWay, null, null, null, null, null);
+            public partial string Text { get => (string)GetValue(TextProperty); set => SetValue(TextProperty, value); }
+
+            public static string GetText(BindableObject view) => (string)view.GetValue(TextProperty);
+            public static void SetText(BindableObject view, string value) => view.SetValue(TextProperty, value);
+            /// <summary>
+            /// Backing BindableProperty for the <see cref = "Number"/> property.
+            /// </summary>
+            public static readonly global::Microsoft.Maui.Controls.BindableProperty NumberProperty = global::Microsoft.Maui.Controls.BindableProperty.CreateAttached("Number", typeof(int), typeof({{defaultTestNamespace}}.{{defaultTestClassName}}), null, Microsoft.Maui.Controls.BindingMode.OneWay, null, null, null, null, null);
+            public partial int Number { get => (int)GetValue(NumberProperty); set => SetValue(NumberProperty, value); }
+
+            public static int GetNumber(BindableObject view) => (int)view.GetValue(NumberProperty);
+            public static void SetNumber(BindableObject view, int value) => view.SetValue(NumberProperty, value);
+        }
+        """;
+
+		await VerifyAttachedSourceGeneratorAsync(source, expectedGenerated);
+	}
+}