Include FontName in Font.GetHashCode (#47674)

* Update Font.cs

* Added test for GetHashCode pr #46816

* Added SkipOnTargetFramework as GetHashCode doesn't include font name in .NET Framework and changed FontFamily to SansSarif as per PR #47674. Fixes #44343. Original PR #46816.

* Update FontTests.cs

* Fix test, skip font if name is equal

Co-authored-by: Dan Moseley <danmose@microsoft.com>
Co-authored-by: Santiago Fernandez Madero <safern@microsoft.com>

src/libraries/System.Drawing.Common/src/System/Drawing/Font.cs

@@ -254,9 +254,7 @@ public override bool Equals([NotNullWhen(true)] object? obj)
         /// </summary>
         public override int GetHashCode()
         {
-            return unchecked((int)((((uint)_fontStyle << 13) | ((uint)_fontStyle >> 19)) ^
-                         (((uint)_fontUnit << 26) | ((uint)_fontUnit >> 6)) ^
-                         (((uint)_fontSize << 7) | ((uint)_fontSize >> 25))));
+            return HashCode.Combine(Name, Style, Size, Unit);
         }
 
         /// <summary>

src/libraries/System.Drawing.Common/tests/FontTests.cs

@@ -978,5 +978,22 @@ private static void VerifyFont(Font font, string expectedName, float expectedEmS
             Assert.False(font.IsSystemFont);
             Assert.Empty(font.SystemFontName);
         }
+
+        [ConditionalFact(Helpers.IsDrawingSupported)]
+        [SkipOnTargetFramework(TargetFrameworkMonikers.NetFramework, "GetHashCode doesn't include font name in .NET Framework")]
+        public void GetHashCode_DifferentNameSameSizeStyleUnit_HashCodeIsNotSame()
+        {
+            using FontFamily family1 = FontFamily.GenericSansSerif;
+            using var font1 = new Font(family1, 1, FontStyle.Bold, GraphicsUnit.Point);
+
+            using FontFamily family2 = FontFamily.GenericMonospace;
+            using var font2 = new Font(family2, 1, FontStyle.Bold, GraphicsUnit.Point);
+            // This test depends on machine setup and whether the fonts we use are installed or not.
+            // If not installed we could get the same font for the two Font families we are testing for.
+            if (font1.Name.Equals(font2.Name, StringComparison.OrdinalIgnoreCase))
+                return;
+
+            Assert.NotEqual(font1.GetHashCode(), font2.GetHashCode());
+        }
     }
 }