1 files changed, 19 insertions, 0 deletions
diff --git a/src/csharp/Grpc.Core.Tests/MetadataTest.cs b/src/csharp/Grpc.Core.Tests/MetadataTest.cs
index 8916731757..d85d7572a6 100644
--- a/src/csharp/Grpc.Core.Tests/MetadataTest.cs
+++ b/src/csharp/Grpc.Core.Tests/MetadataTest.cs
@@ -66,11 +66,30 @@ namespace Grpc.Core.Tests
             new Metadata.Entry("0123456789abc", "XYZ");
             new Metadata.Entry("-abc", "XYZ");
             new Metadata.Entry("a_bc_", "XYZ");
+            new Metadata.Entry("abc.xyz", "XYZ");
+            new Metadata.Entry("abc.xyz-bin", new byte[] {1, 2, 3});
             Assert.Throws(typeof(ArgumentException), () => new Metadata.Entry("abc[", "xyz"));
             Assert.Throws(typeof(ArgumentException), () => new Metadata.Entry("abc/", "xyz"));
         }
 
         [Test]
+        public void KeysAreNormalized_UppercaseKey()
+        {
+            var uppercaseKey = "ABC";
+            var entry = new Metadata.Entry(uppercaseKey, "XYZ");
+            Assert.AreEqual("abc", entry.Key);
+        }
+
+        [Test]
+        public void KeysAreNormalized_LowercaseKey()
+        {
+            var lowercaseKey = "abc";
+            var entry = new Metadata.Entry(lowercaseKey, "XYZ");
+            // no allocation if key already lowercase
+            Assert.AreSame(lowercaseKey, entry.Key);
+        }
+
+        [Test]
         public void Entry_ConstructionPreconditions()
         {
             Assert.Throws(typeof(ArgumentNullException), () => new Metadata.Entry(null, "xyz"));