Add New Enum Description Converter

src/CommunityToolkit.Maui.UnitTests/Converters/EnumDescriptionConverterTests.cs

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+using Xunit;
+
+using CommunityToolkit.Maui.Converters;
+
+using System.ComponentModel;
+using System.ComponentModel.DataAnnotations;
+
+namespace CommunityToolkit.Maui.UnitTests.Converters;
+
+public class EnumDescriptionConverterTests : BaseOneWayConverterTest<EnumDescriptionConverter>
+{
+   enum TestEnum
+	{
+		[Display(Name = "Display Name")]
+		WithDisplay,
+		[Description("Description Text")]
+		WithDescription,
+		NoAttribute
+	}
+
+	enum MultiAttributeEnum
+	{
+		[Display(Name = "Display Name")]
+		[Description("Description Text")]
+		Both,
+		[Display(Name = "")]
+		[Description("Description Text")]
+		EmptyDisplay,
+		[Display(Name = " ")]
+		[Description("Description Text")]
+		WhitespaceDisplay,
+		[Description("")]
+		EmptyDescription,
+	}
+
+  [Fact]
+  public void ConvertFrom_ThrowsArgumentNullException_WhenNull()
+  {
+	var converter = (ICommunityToolkitValueConverter)new EnumDescriptionConverter();
+	Assert.Throws<ArgumentNullException>(() => converter.Convert(null, typeof(string), null, null));
+  }
+
+	[Fact]
+	public void ConvertFrom_FallbackToValueToString_WhenInvalidEnumValue()
+	{
+		var converter = new EnumDescriptionConverter();
+		// Cast an int not defined in MultiAttributeEnum
+		var invalid = (MultiAttributeEnum)999;
+		var result = converter.ConvertFrom(invalid);
+		Assert.Equal("999", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_ReturnsDisplayName()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(TestEnum.WithDisplay);
+		Assert.Equal("Display Name", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_ReturnsDescriptionText()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(TestEnum.WithDescription);
+		Assert.Equal("Description Text", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_ReturnsEnumName_WhenNoAttribute()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(TestEnum.NoAttribute);
+		Assert.Equal("NoAttribute", result);
+	}
+
+
+  [Fact]
+	public void ConvertFrom_DisplayTakesPrecedence_WhenBothAttributes()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(MultiAttributeEnum.Both);
+		Assert.Equal("Display Name", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_FallbackToDescription_WhenDisplayEmpty()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(MultiAttributeEnum.EmptyDisplay);
+		Assert.Equal("Description Text", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_FallbackToDescription_WhenDisplayWhitespace()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(MultiAttributeEnum.WhitespaceDisplay);
+		Assert.Equal("Description Text", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_FallbackToEnumName_WhenDescriptionEmpty()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(MultiAttributeEnum.EmptyDescription);
+		Assert.Equal("EmptyDescription", result);
+	}
+
+	#region DisplayAttribute Localization & Edge Cases
+
+	public class TestResources
+	{
+		public static string LocalizedDisplay => "Localized Display";
+		public static int NonStringResource => 42;
+	}
+
+	enum LocalizedEnum
+	{
+		[Display(Name = "LocalizedDisplay", ResourceType = typeof(TestResources))]
+		Localized,
+		[Display(Name = "MissingResource", ResourceType = typeof(TestResources))]
+		MissingResource,
+		[Display(Name = null)]
+		NullName,
+		[Display(Name = " ")]
+		WhitespaceName,
+		[Display(Name = "NonStringResource", ResourceType = typeof(TestResources))]
+		NonStringResource,
+	}
+
+	[Fact]
+	public void ConvertFrom_ReturnsLocalizedDisplay_WhenResourceTypeSet()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(LocalizedEnum.Localized);
+		Assert.Equal("Localized Display", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_FallbackToName_WhenResourceMissing()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(LocalizedEnum.MissingResource);
+		Assert.Equal("MissingResource", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_FallbackToEnumName_WhenDisplayNameNull()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(LocalizedEnum.NullName);
+		Assert.Equal("NullName", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_FallbackToEnumName_WhenDisplayNameWhitespace()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(LocalizedEnum.WhitespaceName);
+		Assert.Equal("WhitespaceName", result);
+	}
+
+	[Fact]
+	public void ConvertFrom_FallbackToEnumName_WhenGetNameThrows()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(LocalizedEnum.NonStringResource);
+		Assert.Equal("NonStringResource", result);
+	}
+
+	#endregion
+
+	#region DescriptionAttribute Edge Cases
+
+	enum DescriptionEdgeEnum
+	{
+		[Description("")]
+		EmptyDescription,
+	}
+
+	[Fact]
+	public void ConvertFrom_FallbackToEnumName_WhenDescriptionEmptyEdge()
+	{
+		var converter = new EnumDescriptionConverter();
+		var result = converter.ConvertFrom(DescriptionEdgeEnum.EmptyDescription);
+		Assert.Equal("EmptyDescription", result);
+	}
+
+	#endregion
+}

src/CommunityToolkit.Maui/Converters/EnumDescriptionConverter.cs

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+using System.ComponentModel;
+using System.ComponentModel.DataAnnotations;
+using System.Globalization;
+using System.Reflection;
+
+namespace CommunityToolkit.Maui.Converters;
+
+/// <summary>
+/// Converts an <see cref="Enum"/> value to its display string using <see cref="DisplayAttribute"/> or <see cref="DescriptionAttribute"/>.
+/// </summary>
+[AcceptEmptyServiceProvider]
+public partial class EnumDescriptionConverter : BaseConverterOneWay<Enum, string>
+{
+	/// <inheritdoc/>
+	public override string DefaultConvertReturnValue { get; set; } = string.Empty;
+
+	/// <summary>
+	/// Converts an <see cref="Enum"/> value to its display string.
+	/// </summary>
+	/// <param name="value">The enum value to convert.</param>
+	/// <param name="culture">The culture to use for the conversion (not used).</param>
+	/// <returns>
+	/// The value of the <see cref="DisplayAttribute.Name"/> if defined;
+	/// otherwise the value of the <see cref="DescriptionAttribute.Description"/> if defined;
+	/// otherwise the enum name as a string.
+	/// </returns>
+	public override string ConvertFrom(Enum value, CultureInfo? culture = null)
+	{
+		ArgumentNullException.ThrowIfNull(value);
+		var fieldInfo = value.GetType().GetField(value.ToString());
+
+		// Check for DisplayAttribute first (common in data annotations)
+		var displayAttr = fieldInfo?.GetCustomAttribute<DisplayAttribute>();
+		if (displayAttr is not null)
+		{
+			string? displayName = null;
+			try
+			{
+				displayName = displayAttr.GetName();
+			}
+			catch
+			{
+				// If GetName throws, fallback to Name
+				displayName = null;
+			}
+			if (!string.IsNullOrWhiteSpace(displayName))
+			{
+				return displayName;
+			}
+			if (!string.IsNullOrWhiteSpace(displayAttr.Name))
+			{
+				return displayAttr.Name;
+			}
+		}
+
+		// Fallback to DescriptionAttribute
+		var descriptionAttr = fieldInfo?.GetCustomAttribute<DescriptionAttribute>();
+		if (descriptionAttr is not null && !string.IsNullOrWhiteSpace(descriptionAttr.Description))
+		{
+			return descriptionAttr.Description;
+		}
+
+		return value.ToString(); // Fallback to enum name if no attribute found
+	}
+
+	// ConvertBackTo is sealed in BaseConverterOneWay and cannot be overridden.
+}