Fix Color equality regression for derived types by sealing the record

src/Graphics/src/Graphics/Color.cs

@@ -11,10 +11,15 @@ namespace Microsoft.Maui.Graphics
 	/// <summary>
 	/// Represents an RGBA color with floating-point components in the range of 0.0 to 1.0.
 	/// </summary>
+	/// <remarks>
+	/// <see cref="Color"/> is a sealed record type, so equality (via <see cref="Equals(Color?)"/>, <c>==</c>, and <c>!=</c>)
+	/// is always value-based, comparing the underlying ARGB representation regardless of how the instance was created.
+	/// Sealing prevents subclassing, which guarantees this value-based equality can never be silently broken by a derived type.
+	/// </remarks>
 	[DebuggerDisplay("Red={Red}, Green={Green}, Blue={Blue}, Alpha={Alpha}")]
 	[TypeConverter(typeof(Converters.ColorTypeConverter))]
 	[ImmutableObject(true)]
-	public record class Color
+	public sealed record class Color
 	{
 		/// <summary>
 		/// The red component of the color, ranging from 0.0 to 1.0.
@@ -119,7 +124,7 @@ public override string ToString()
 		/// <summary>
 		/// Determines whether the specified <see cref="Color"/> is equal to the current color using byte-precision comparison.
 		/// </summary>
-		public virtual bool Equals(Color? other)
+		public bool Equals(Color? other)
 		{
 			if (other is null)
 				return false;

src/Graphics/src/Graphics/PublicAPI/net-android/PublicAPI.Unshipped.txt

@@ -1,12 +1,9 @@
 #nullable enable
-Microsoft.Maui.Graphics.Color.Color(Microsoft.Maui.Graphics.Color! original) -> void
 override Microsoft.Maui.Graphics.Color.Equals(object? obj) -> bool
 static Microsoft.Maui.Graphics.Color.operator !=(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
 static Microsoft.Maui.Graphics.Color.operator ==(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
-virtual Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
-virtual Microsoft.Maui.Graphics.Color.EqualityContract.get -> System.Type!
-virtual Microsoft.Maui.Graphics.Color.PrintMembers(System.Text.StringBuilder! builder) -> bool
-virtual Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
+Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
+Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
 Microsoft.Maui.Graphics.Color.AddLuminosity(float delta) -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.ToArgbHex(bool includeAlpha = false) -> string!
 Microsoft.Maui.Graphics.Color.ToRgbaHex(bool includeAlpha = false) -> string!

src/Graphics/src/Graphics/PublicAPI/net-ios/PublicAPI.Unshipped.txt

@@ -1,12 +1,9 @@
 #nullable enable
-Microsoft.Maui.Graphics.Color.Color(Microsoft.Maui.Graphics.Color! original) -> void
 override Microsoft.Maui.Graphics.Color.Equals(object? obj) -> bool
 static Microsoft.Maui.Graphics.Color.operator !=(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
 static Microsoft.Maui.Graphics.Color.operator ==(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
-virtual Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
-virtual Microsoft.Maui.Graphics.Color.EqualityContract.get -> System.Type!
-virtual Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
-virtual Microsoft.Maui.Graphics.Color.PrintMembers(System.Text.StringBuilder! builder) -> bool
+Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
+Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
 Microsoft.Maui.Graphics.Color.AsPaint() -> Microsoft.Maui.Graphics.Paint!
 Microsoft.Maui.Graphics.Color.MultiplyAlpha(float multiplyBy) -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.WithAlpha(float alpha) -> Microsoft.Maui.Graphics.Color!

src/Graphics/src/Graphics/PublicAPI/net-maccatalyst/PublicAPI.Unshipped.txt

@@ -1,12 +1,9 @@
 #nullable enable
-Microsoft.Maui.Graphics.Color.Color(Microsoft.Maui.Graphics.Color! original) -> void
 override Microsoft.Maui.Graphics.Color.Equals(object? obj) -> bool
 static Microsoft.Maui.Graphics.Color.operator !=(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
 static Microsoft.Maui.Graphics.Color.operator ==(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
-virtual Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
-virtual Microsoft.Maui.Graphics.Color.EqualityContract.get -> System.Type!
-virtual Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
-virtual Microsoft.Maui.Graphics.Color.PrintMembers(System.Text.StringBuilder! builder) -> bool
+Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
+Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
 Microsoft.Maui.Graphics.Color.AsPaint() -> Microsoft.Maui.Graphics.Paint!
 Microsoft.Maui.Graphics.Color.MultiplyAlpha(float multiplyBy) -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.WithAlpha(float alpha) -> Microsoft.Maui.Graphics.Color!

src/Graphics/src/Graphics/PublicAPI/net-macos/PublicAPI.Unshipped.txt

@@ -1,12 +1,9 @@
 #nullable enable
-Microsoft.Maui.Graphics.Color.Color(Microsoft.Maui.Graphics.Color! original) -> void
 override Microsoft.Maui.Graphics.Color.Equals(object? obj) -> bool
 static Microsoft.Maui.Graphics.Color.operator !=(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
 static Microsoft.Maui.Graphics.Color.operator ==(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
-virtual Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
-virtual Microsoft.Maui.Graphics.Color.EqualityContract.get -> System.Type!
-virtual Microsoft.Maui.Graphics.Color.PrintMembers(System.Text.StringBuilder! builder) -> bool
-virtual Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
+Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
+Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
 Microsoft.Maui.Graphics.Color.AddLuminosity(float delta) -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.GetComplementary() -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.ToArgbHex(bool includeAlpha = false) -> string!

src/Graphics/src/Graphics/PublicAPI/net-tizen/PublicAPI.Unshipped.txt

@@ -1,12 +1,9 @@
 #nullable enable
-Microsoft.Maui.Graphics.Color.Color(Microsoft.Maui.Graphics.Color! original) -> void
 override Microsoft.Maui.Graphics.Color.Equals(object? obj) -> bool
 static Microsoft.Maui.Graphics.Color.operator !=(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
 static Microsoft.Maui.Graphics.Color.operator ==(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
-virtual Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
-virtual Microsoft.Maui.Graphics.Color.EqualityContract.get -> System.Type!
-virtual Microsoft.Maui.Graphics.Color.PrintMembers(System.Text.StringBuilder! builder) -> bool
-virtual Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
+Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
+Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
 Microsoft.Maui.Graphics.Color.AddLuminosity(float delta) -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.GetComplementary() -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.ToArgbHex(bool includeAlpha = false) -> string!

src/Graphics/src/Graphics/PublicAPI/net-windows/PublicAPI.Unshipped.txt

@@ -1,12 +1,9 @@
 #nullable enable
-Microsoft.Maui.Graphics.Color.Color(Microsoft.Maui.Graphics.Color! original) -> void
 override Microsoft.Maui.Graphics.Color.Equals(object? obj) -> bool
 static Microsoft.Maui.Graphics.Color.operator !=(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
 static Microsoft.Maui.Graphics.Color.operator ==(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
-virtual Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
-virtual Microsoft.Maui.Graphics.Color.EqualityContract.get -> System.Type!
-virtual Microsoft.Maui.Graphics.Color.PrintMembers(System.Text.StringBuilder! builder) -> bool
-virtual Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
+Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
+Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
 Microsoft.Maui.Graphics.Color.AddLuminosity(float delta) -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.GetComplementary() -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.ToArgbHex(bool includeAlpha = false) -> string!

src/Graphics/src/Graphics/PublicAPI/net/PublicAPI.Unshipped.txt

@@ -1,12 +1,9 @@
 #nullable enable
-Microsoft.Maui.Graphics.Color.Color(Microsoft.Maui.Graphics.Color! original) -> void
 override Microsoft.Maui.Graphics.Color.Equals(object? obj) -> bool
 static Microsoft.Maui.Graphics.Color.operator !=(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
 static Microsoft.Maui.Graphics.Color.operator ==(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
-virtual Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
-virtual Microsoft.Maui.Graphics.Color.EqualityContract.get -> System.Type!
-virtual Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
-virtual Microsoft.Maui.Graphics.Color.PrintMembers(System.Text.StringBuilder! builder) -> bool
+Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
+Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
 Microsoft.Maui.Graphics.Color.AsPaint() -> Microsoft.Maui.Graphics.Paint!
 Microsoft.Maui.Graphics.Color.MultiplyAlpha(float multiplyBy) -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.WithAlpha(float alpha) -> Microsoft.Maui.Graphics.Color!

src/Graphics/src/Graphics/PublicAPI/netstandard/PublicAPI.Unshipped.txt

@@ -1,12 +1,9 @@
 #nullable enable
-Microsoft.Maui.Graphics.Color.Color(Microsoft.Maui.Graphics.Color! original) -> void
 override Microsoft.Maui.Graphics.Color.Equals(object? obj) -> bool
 static Microsoft.Maui.Graphics.Color.operator !=(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
 static Microsoft.Maui.Graphics.Color.operator ==(Microsoft.Maui.Graphics.Color? left, Microsoft.Maui.Graphics.Color? right) -> bool
-virtual Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
-virtual Microsoft.Maui.Graphics.Color.EqualityContract.get -> System.Type!
-virtual Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
-virtual Microsoft.Maui.Graphics.Color.PrintMembers(System.Text.StringBuilder! builder) -> bool
+Microsoft.Maui.Graphics.Color.<Clone>$() -> Microsoft.Maui.Graphics.Color!
+Microsoft.Maui.Graphics.Color.Equals(Microsoft.Maui.Graphics.Color? other) -> bool
 Microsoft.Maui.Graphics.Color.AsPaint() -> Microsoft.Maui.Graphics.Paint!
 Microsoft.Maui.Graphics.Color.MultiplyAlpha(float multiplyBy) -> Microsoft.Maui.Graphics.Color!
 Microsoft.Maui.Graphics.Color.WithAlpha(float alpha) -> Microsoft.Maui.Graphics.Color!

src/Graphics/tests/Graphics.Tests/ColorUnitTests.cs

@@ -468,5 +468,37 @@ public void TestParseAllBuiltInColors()
 				Assert.Equal(expected, actual);
 			}
 		}
+
+		[Fact]
+		public void ColorTypeIsSealed()
+		{
+			// Sealing Color guarantees every instance shares the same runtime type, so its
+			// record-generated equality (based on the ARGB value) can never be broken by a subclass.
+			Assert.True(typeof(Color).IsSealed);
+		}
+
+		[Fact]
+		public void EqualsIsValueBasedForSameArgbValue()
+		{
+			var color1 = new Color(1f, 0f, 0f, 1f);
+			var color2 = new Color(1f, 0f, 0f, 1f);
+
+			Assert.Equal(color1, color2);
+			Assert.True(color1 == color2);
+			Assert.True(color1.Equals(color2));
+			Assert.True(EqualityComparer<Color>.Default.Equals(color1, color2));
+			Assert.Equal(color1.GetHashCode(), color2.GetHashCode());
+		}
+
+		[Fact]
+		public void EqualsIsFalseForDifferentArgbValue()
+		{
+			var color1 = new Color(1f, 0f, 0f, 1f);
+			var color2 = new Color(0f, 1f, 0f, 1f);
+
+			Assert.NotEqual(color1, color2);
+			Assert.True(color1 != color2);
+			Assert.False(color1.Equals(color2));
+		}
 	}
 }