Copied dotnet code from CosmosDB repository

dotnet/src/HybridRow.Tests.Unit/CustomerSchema/PostalCode.cs

@@ -0,0 +1,42 @@
+// ------------------------------------------------------------
+//  Copyright (c) Microsoft Corporation.  All rights reserved.
+// ------------------------------------------------------------
+
+#pragma warning disable SA1401 // Fields should be private
+
+namespace Microsoft.Azure.Cosmos.Serialization.HybridRow.Tests.Unit.CustomerSchema
+{
+    internal sealed class PostalCode
+    {
+        public int Zip;
+        public short? Plus4;
+
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(null, obj))
+            {
+                return false;
+            }
+
+            if (object.ReferenceEquals(this, obj))
+            {
+                return true;
+            }
+
+            return obj is PostalCode && this.Equals((PostalCode)obj);
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked
+            {
+                return (this.Zip * 397) ^ this.Plus4.GetHashCode();
+            }
+        }
+
+        private bool Equals(PostalCode other)
+        {
+            return this.Zip == other.Zip && this.Plus4 == other.Plus4;
+        }
+    }
+}