Forward all DataAnnotations attribute for [ObservableProperty]

Author: Sergio0694

CommunityToolkit.Mvvm.SourceGenerators/ComponentModel/ObservablePropertyGenerator.Execute.cs

@@ -118,8 +118,19 @@ internal static class Execute
                     continue;
                 }
 
-                // Track the current validation attribute, if applicable
-                if (attributeData.AttributeClass?.InheritsFromFullyQualifiedName("global::System.ComponentModel.DataAnnotations.ValidationAttribute") == true)
+                // Track the current attribute for forwarding if applicable. The following attributes are special cased:
+                //   - Validation attributes (System.ComponentModel.DataAnnotations.ValidationAttribute)
+                //   - Display attributes (System.ComponentModel.DataAnnotations.DisplayAttribute)
+                //   - UI hint attributes(System.ComponentModel.DataAnnotations.UIHintAttribute)
+                //   - Scaffold column attributes (System.ComponentModel.DataAnnotations.ScaffoldColumnAttribute)
+                //   - Editable attributes (System.ComponentModel.DataAnnotations.EditableAttribute)
+                //   - Key attributes (System.ComponentModel.DataAnnotations.KeyAttribute)
+                if (attributeData.AttributeClass?.InheritsFromFullyQualifiedName("global::System.ComponentModel.DataAnnotations.ValidationAttribute") == true ||
+                    attributeData.AttributeClass?.HasOrInheritsFromFullyQualifiedName("global::System.ComponentModel.DataAnnotations.UIHintAttribute") == true ||
+                    attributeData.AttributeClass?.HasOrInheritsFromFullyQualifiedName("global::System.ComponentModel.DataAnnotations.ScaffoldColumnAttribute") == true ||
+                    attributeData.AttributeClass?.HasFullyQualifiedName("global::System.ComponentModel.DataAnnotations.DisplayAttribute") == true ||
+                    attributeData.AttributeClass?.HasFullyQualifiedName("global::System.ComponentModel.DataAnnotations.EditableAttribute") == true ||
+                    attributeData.AttributeClass?.HasFullyQualifiedName("global::System.ComponentModel.DataAnnotations.KeyAttribute") == true)
                 {
                     validationAttributes.Add(AttributeInfo.From(attributeData));
                 }

tests/CommunityToolkit.Mvvm.UnitTests/Test_ObservablePropertyAttribute.cs

@@ -658,6 +658,46 @@ public void Test_ObservableProperty_InheritedModelWithCommandUsingInheritedObser
         Assert.IsTrue(model.SaveCommand.CanExecute(null));
     }
 
+    [TestMethod]
+    public void Test_ObservableProperty_ForwardsSpecialCasesDataAnnotationAttributes()
+    {
+        PropertyInfo propertyInfo = typeof(ModelWithAdditionalDataAnnotationAttributes).GetProperty(nameof(ModelWithAdditionalDataAnnotationAttributes.Name))!;
+
+        DisplayAttribute? displayAttribute = (DisplayAttribute?)propertyInfo.GetCustomAttribute(typeof(DisplayAttribute));
+
+        Assert.IsNotNull(displayAttribute);
+        Assert.AreEqual(displayAttribute!.Name, "MyProperty");
+        Assert.AreEqual(displayAttribute.ResourceType, typeof(List<double>));
+        Assert.AreEqual(displayAttribute.Prompt, "Foo bar baz");
+
+        KeyAttribute? keyAttribute = (KeyAttribute?)propertyInfo.GetCustomAttribute(typeof(KeyAttribute));
+
+        Assert.IsNotNull(keyAttribute);
+
+        EditableAttribute? editableAttribute = (EditableAttribute?)propertyInfo.GetCustomAttribute(typeof(EditableAttribute));
+
+        Assert.IsNotNull(keyAttribute);
+        Assert.IsTrue(editableAttribute!.AllowEdit);
+
+        UIHintAttribute? uiHintAttribute = (UIHintAttribute?)propertyInfo.GetCustomAttribute(typeof(UIHintAttribute));
+
+        Assert.IsNotNull(uiHintAttribute);
+        Assert.AreEqual(uiHintAttribute!.UIHint, "MyControl");
+        Assert.AreEqual(uiHintAttribute.PresentationLayer, "WPF");
+        Assert.AreEqual(uiHintAttribute.ControlParameters.Count, 3);
+        Assert.IsTrue(uiHintAttribute.ControlParameters.ContainsKey("Foo"));
+        Assert.IsTrue(uiHintAttribute.ControlParameters.ContainsKey("Bar"));
+        Assert.IsTrue(uiHintAttribute.ControlParameters.ContainsKey("Baz"));
+        Assert.AreEqual(uiHintAttribute.ControlParameters["Foo"], 42);
+        Assert.AreEqual(uiHintAttribute.ControlParameters["Bar"], 3.14);
+        Assert.AreEqual(uiHintAttribute.ControlParameters["Baz"], "Hello");
+
+        ScaffoldColumnAttribute? scaffoldColumnAttribute = (ScaffoldColumnAttribute?)propertyInfo.GetCustomAttribute(typeof(ScaffoldColumnAttribute));
+
+        Assert.IsNotNull(scaffoldColumnAttribute);
+        Assert.IsTrue(scaffoldColumnAttribute!.Scaffold);
+    }
+
     public abstract partial class BaseViewModel : ObservableObject
     {
         public string? Content { get; set; }
@@ -1066,4 +1106,15 @@ public override void Save()
         {
         }
     }
+
+    public partial class ModelWithAdditionalDataAnnotationAttributes : ObservableValidator
+    {
+        [ObservableProperty]
+        [Display(Name = "MyProperty", ResourceType = typeof(List<double>), Prompt = "Foo bar baz")]
+        [Key]
+        [Editable(true)]
+        [UIHint("MyControl", "WPF", new object[] { "Foo", 42, "Bar", 3.14, "Baz", "Hello" })]
+        [ScaffoldColumn(true)]
+        private string? name;
+    }
 }