9 files changed, 512 insertions, 1 deletions

diff --git a/src/DotNetOpenAuth.Test/OpenId/ChannelElements/ExtensionsBindingElementTests.cs b/src/DotNetOpenAuth.Test/OpenId/ChannelElements/ExtensionsBindingElementTests.cs
index 298b6d4..a9bc5d2 100644
--- a/src/DotNetOpenAuth.Test/OpenId/ChannelElements/ExtensionsBindingElementTests.cs
+++ b/src/DotNetOpenAuth.Test/OpenId/ChannelElements/ExtensionsBindingElementTests.cs
@@ -94,6 +94,28 @@ namespace DotNetOpenAuth.Test.OpenId.ChannelElements {
 			Assert.Inconclusive("Not yet implemented.");
 		}
 
+		/// <summary>
+		/// Verifies that two extensions with the same TypeURI cannot be applied to the same message.
+		/// </summary>
+		/// <remarks>
+		/// OpenID Authentication 2.0 section 12 states that
+		/// "A namespace MUST NOT be assigned more than one alias in the same message".
+		/// </remarks>
+		[TestMethod]
+		public void TwoExtensionsSameTypeUri() {
+			IOpenIdMessageExtension request1 = new MockOpenIdExtension("requestPart1", "requestData1");
+			IOpenIdMessageExtension request2 = new MockOpenIdExtension("requestPart2", "requestData2");
+			try {
+				ExtensionTestUtilities.Roundtrip(
+					Protocol.Default,
+					new IOpenIdMessageExtension[] { request1, request2 },
+					new IOpenIdMessageExtension[0]);
+				Assert.Fail("Expected ProtocolException not thrown.");
+			} catch (AssertFailedException ex) {
+				Assert.IsInstanceOfType(ex.InnerException, typeof(ProtocolException));
+			}
+		}
+
 		private static IEnumerable<string> GetAliases(IDictionary<string, string> extraData) {
 			Regex regex = new Regex(@"^openid\.ns\.(\w+)");
 			return from key in extraData.Keys
diff --git a/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeExchangeRoundtripTests.cs b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeExchangeRoundtripTests.cs
new file mode 100644
index 0000000..ac86156
--- /dev/null
+++ b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeExchangeRoundtripTests.cs
@@ -0,0 +1,53 @@
+//-----------------------------------------------------------------------
+// <copyright file="AttributeExchangeRoundtripTests.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.Test.OpenId.Extensions {
+	using DotNetOpenAuth.OpenId;
+	using DotNetOpenAuth.OpenId.Extensions.AttributeExchange;
+	using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+	[TestClass]
+	public class AttributeExchangeRoundtripTests : OpenIdTestBase {
+		private const string NicknameTypeUri = WellKnownAttributes.Name.Alias;
+		private const string EmailTypeUri = WellKnownAttributes.Contact.Email;
+		private const string IncrementingAttribute = "http://incatt";
+		private int incrementingAttributeValue = 1;
+
+		[TestMethod]
+		public void Fetch() {
+			var request = new FetchRequest();
+			request.AddAttribute(new AttributeRequest(NicknameTypeUri));
+			request.AddAttribute(new AttributeRequest(EmailTypeUri, false, int.MaxValue));
+
+			var response = new FetchResponse();
+			response.AddAttribute(new AttributeValues(NicknameTypeUri, "Andrew"));
+			response.AddAttribute(new AttributeValues(EmailTypeUri, "a@a.com", "b@b.com"));
+
+			ExtensionTestUtilities.Roundtrip(Protocol.Default, new[] { request }, new[] { response });
+		}
+
+		[TestMethod]
+		public void Store() {
+			var request = new StoreRequest();
+			var newAttribute = new AttributeValues(
+				IncrementingAttribute,
+				"val" + (incrementingAttributeValue++).ToString(),
+				"val" + (incrementingAttributeValue++).ToString());
+			request.AddAttribute(newAttribute);
+
+			var successResponse = new StoreResponse();
+			successResponse.Succeeded = true;
+
+			ExtensionTestUtilities.Roundtrip(Protocol.Default, new[] { request }, new[] { successResponse });
+
+			var failureResponse = new StoreResponse();
+			failureResponse.Succeeded = false;
+			failureResponse.FailureReason = "Some error";
+
+			ExtensionTestUtilities.Roundtrip(Protocol.Default, new[] { request }, new[] { failureResponse });
+		}
+	}
+}
diff --git a/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeRequestTests.cs b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeRequestTests.cs
new file mode 100644
index 0000000..228bda3
--- /dev/null
+++ b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeRequestTests.cs
@@ -0,0 +1,85 @@
+//-----------------------------------------------------------------------
+// <copyright file="AttributeRequestTests.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.Test.OpenId.Extensions {
+	using System;
+	using DotNetOpenAuth.OpenId.Extensions.AttributeExchange;
+	using DotNetOpenAuth.Test.OpenId;
+	using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+	[TestClass]
+	public class AttributeRequestTests : OpenIdTestBase {
+		[TestMethod]
+		public void CtorDefault() {
+			AttributeRequest req = new AttributeRequest();
+			Assert.AreEqual(1, req.Count);
+			Assert.IsNull(req.TypeUri);
+			Assert.IsFalse(req.IsRequired);
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentException))]
+		public void CtorEmptyTypeUri() {
+			new AttributeRequest(string.Empty);
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentNullException))]
+		public void CtorNullTypeUri() {
+			new AttributeRequest(null);
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+		public void CtorCountZero() {
+			new AttributeRequest(WellKnownAttributes.Contact.Email, false, 0);
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+		public void CtorCountNegative() {
+			new AttributeRequest(WellKnownAttributes.Contact.Email, false, -1);
+		}
+
+		[TestMethod]
+		public void CtorFull() {
+			var req = new AttributeRequest(WellKnownAttributes.Contact.Email, true, 5);
+			Assert.AreEqual(WellKnownAttributes.Contact.Email, req.TypeUri);
+			Assert.IsTrue(req.IsRequired);
+			Assert.AreEqual(5, req.Count);
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+		public void SetCountZero() {
+			var req = new AttributeRequest();
+			req.Count = 0;
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentOutOfRangeException))]
+		public void SetCountNegative() {
+			var req = new AttributeRequest();
+			req.Count = -1;
+		}
+
+		[TestMethod]
+		public void EqualityTests() {
+			var req1 = new AttributeRequest();
+			var req2 = new AttributeRequest();
+			Assert.AreEqual(req1, req2);
+
+			req1.IsRequired = true;
+			Assert.AreNotEqual(req1, req2);
+			req2.IsRequired = true;
+			Assert.AreEqual(req1, req2);
+
+			req1.Count = 3;
+			Assert.AreNotEqual(req1, req2);
+			req2.Count = 3;
+			Assert.AreEqual(req1, req2);
+
+			req1.TypeUri = "http://hi";
+			Assert.AreNotEqual(req1, req2);
+			req2.TypeUri = "http://hi";
+			Assert.AreEqual(req1, req2);
+		}
+	}
+}
diff --git a/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeValuesTests.cs b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeValuesTests.cs
new file mode 100644
index 0000000..1f7e17c
--- /dev/null
+++ b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/AttributeValuesTests.cs
@@ -0,0 +1,62 @@
+//-----------------------------------------------------------------------
+// <copyright file="AttributeValuesTests.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.Test.OpenId.Extensions.AttributeExchange {
+	using System;
+	using System.Collections.Generic;
+	using System.Linq;
+	using System.Text;
+	using DotNetOpenAuth.OpenId.Extensions.AttributeExchange;
+	using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+	[TestClass]
+	public class AttributeValuesTests : OpenIdTestBase {
+		[TestMethod]
+		public void Ctor() {
+			var att = new AttributeValues();
+			Assert.IsNull(att.TypeUri);
+			Assert.IsNotNull(att.Values);
+			Assert.AreEqual(0, att.Values.Count);
+
+			att = new AttributeValues("http://att");
+			Assert.AreEqual("http://att", att.TypeUri);
+			Assert.IsNotNull(att.Values);
+			Assert.AreEqual(0, att.Values.Count);
+
+			att = new AttributeValues("http://att", "value1", "value2");
+			Assert.AreEqual("http://att", att.TypeUri);
+			Assert.IsNotNull(att.Values);
+			Assert.AreEqual(2, att.Values.Count);
+			Assert.AreEqual("value1", att.Values[0]);
+			Assert.AreEqual("value2", att.Values[1]);
+		}
+
+		/// <summary>
+		/// Verifies the Equals method.
+		/// </summary>
+		[TestMethod]
+		public void EqualityTests() {
+			var att1 = new AttributeValues();
+			var att2 = new AttributeValues();
+			Assert.AreEqual(att1, att2);
+
+			att1.TypeUri = "http://att1";
+			Assert.AreNotEqual(att1, att2);
+			att2.TypeUri = "http://att1";
+			Assert.AreEqual(att1, att2);
+
+			att1.Values.Add("value1");
+			Assert.AreNotEqual(att1, att2);
+			att2.Values.Add("value1");
+			Assert.AreEqual(att1, att2);
+
+			// Values that are out of order should not be considered equal.
+			att1.Values.Add("value2");
+			att2.Values.Insert(0, "value2");
+			Assert.AreNotEqual(att1, att2);
+		}
+	}
+}
diff --git a/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/FetchRequestTests.cs b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/FetchRequestTests.cs
new file mode 100644
index 0000000..5374794
--- /dev/null
+++ b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/FetchRequestTests.cs
@@ -0,0 +1,99 @@
+//-----------------------------------------------------------------------
+// <copyright file="FetchRequestTests.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.Test.OpenId.Extensions {
+	using System;
+	using DotNetOpenAuth.OpenId.Extensions.AttributeExchange;
+	using DotNetOpenAuth.Test.OpenId;
+	using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+	[TestClass]
+	public class FetchRequestTests : OpenIdTestBase {
+		[TestMethod, ExpectedException(typeof(ArgumentNullException))]
+		public void AddAttributeRequestNull() {
+			new FetchRequest().AddAttribute(null);
+		}
+
+		[TestMethod]
+		public void AddAttributeRequest() {
+			var req = new FetchRequest();
+			req.AddAttribute(new AttributeRequest() { TypeUri = "http://someUri" });
+		}
+
+		[TestMethod]
+		public void AddAttributeRequestStrangeUri() {
+			var req = new FetchRequest();
+			req.AddAttribute(new AttributeRequest() { TypeUri = "=someUri*who*knows*but*this*is*legal" });
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentException))]
+		public void AddAttributeRequestAgain() {
+			var req = new FetchRequest();
+			req.AddAttribute(new AttributeRequest() { TypeUri = "http://UriTwice" });
+			req.AddAttribute(new AttributeRequest() { TypeUri = "http://UriTwice" });
+		}
+
+		[TestMethod]
+		public void RespondSimpleValue() {
+			var req = new AttributeRequest();
+			req.TypeUri = "http://someType";
+			var resp = req.Respond("value");
+			Assert.AreEqual(req.TypeUri, resp.TypeUri);
+			Assert.AreEqual(1, resp.Values.Count);
+			Assert.AreEqual("value", resp.Values[0]);
+		}
+
+		[TestMethod]
+		public void RespondTwoValues() {
+			var req = new AttributeRequest();
+			req.TypeUri = "http://someType";
+			req.Count = 2;
+			var resp = req.Respond("value1", "value2");
+			Assert.AreEqual(req.TypeUri, resp.TypeUri);
+			Assert.AreEqual(2, resp.Values.Count);
+			Assert.AreEqual("value1", resp.Values[0]);
+			Assert.AreEqual("value2", resp.Values[1]);
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentException))]
+		public void RespondTooManyValues() {
+			var req = new AttributeRequest();
+			req.TypeUri = "http://someType";
+			req.Count = 1;
+			req.Respond("value1", "value2");
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentNullException))]
+		public void RespondNull() {
+			var req = new AttributeRequest();
+			req.TypeUri = "http://someType";
+			req.Count = 1;
+			req.Respond(null);
+		}
+
+		[TestMethod]
+		public void EqualityTests() {
+			var req1 = new FetchRequest();
+			var req2 = new FetchRequest();
+			Assert.AreEqual(req1, req2);
+
+			req1.UpdateUrl = new Uri("http://hi");
+			Assert.AreNotEqual(req1, req2);
+			req2.UpdateUrl = new Uri("http://hi");
+			Assert.AreEqual(req1, req2);
+
+			// Add attributes in different orders deliberately.
+			req1.AddAttribute(new AttributeRequest("http://att1"));
+			Assert.AreNotEqual(req1, req2);
+			req2.AddAttribute(new AttributeRequest("http://att2"));
+			Assert.AreNotEqual(req1, req2);
+			req1.AddAttribute(new AttributeRequest("http://att2"));
+			Assert.AreNotEqual(req1, req2);
+			req2.AddAttribute(new AttributeRequest("http://att1"));
+			Assert.AreEqual(req1, req2);
+		}
+	}
+}
diff --git a/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/FetchResponseTests.cs b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/FetchResponseTests.cs
new file mode 100644
index 0000000..3f01498
--- /dev/null
+++ b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/FetchResponseTests.cs
@@ -0,0 +1,63 @@
+//-----------------------------------------------------------------------
+// <copyright file="FetchResponseTests.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenId.Test.OpenId.Extensions {
+	using System;
+	using DotNetOpenAuth.OpenId.Extensions.AttributeExchange;
+	using DotNetOpenAuth.Test.OpenId;
+	using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+	[TestClass]
+	public class FetchResponseTests : OpenIdTestBase {
+		[TestMethod]
+		public void AddAttribute() {
+			var response = new FetchResponse();
+			response.AddAttribute(new AttributeValues("http://someattribute", "Value1"));
+		}
+
+		[TestMethod]
+		public void AddTwoAttributes() {
+			var response = new FetchResponse();
+			response.AddAttribute(new AttributeValues("http://someattribute", "Value1"));
+			response.AddAttribute(new AttributeValues("http://someOtherAttribute", "Value2"));
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentException))]
+		public void AddAttributeTwice() {
+			var response = new FetchResponse();
+			response.AddAttribute(new AttributeValues("http://someattribute", "Value1"));
+			response.AddAttribute(new AttributeValues("http://someattribute", "Value1"));
+		}
+
+		[TestMethod, ExpectedException(typeof(ArgumentNullException))]
+		public void AddAttributeNull() {
+			var response = new FetchResponse();
+			response.AddAttribute(null);
+		}
+
+		[TestMethod]
+		public void EqualityTests() {
+			var response1 = new FetchResponse();
+			var response2 = new FetchResponse();
+			Assert.AreEqual(response1, response2);
+
+			response1.UpdateUrl = new Uri("http://updateurl");
+			Assert.AreNotEqual(response1, response2);
+			response2.UpdateUrl = new Uri("http://updateurl");
+			Assert.AreEqual(response1, response2);
+
+			// Add attributes in different orders deliberately.
+			response1.AddAttribute(new AttributeValues("http://att1"));
+			Assert.AreNotEqual(response1, response2);
+			response2.AddAttribute(new AttributeValues("http://att2"));
+			Assert.AreNotEqual(response1, response2);
+			response1.AddAttribute(new AttributeValues("http://att2"));
+			Assert.AreNotEqual(response1, response2);
+			response2.AddAttribute(new AttributeValues("http://att1"));
+			Assert.AreEqual(response1, response2);
+		}
+	}
+}
diff --git a/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/StoreRequestTests.cs b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/StoreRequestTests.cs
new file mode 100644
index 0000000..e0fe064
--- /dev/null
+++ b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/StoreRequestTests.cs
@@ -0,0 +1,70 @@
+//-----------------------------------------------------------------------
+// <copyright file="StoreRequestTests.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.Test.OpenId.Extensions.AttributeExchange {
+	using System;
+	using System.Collections.Generic;
+	using System.Linq;
+	using System.Text;
+	using DotNetOpenAuth.Messaging;
+	using DotNetOpenAuth.OpenId.Extensions.AttributeExchange;
+	using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+	[TestClass]
+	public class StoreRequestTests {
+		/// <summary>
+		/// Verifies the constructor behavior.
+		/// </summary>
+		[TestMethod]
+		public void Ctor() {
+			var req = new StoreRequest();
+			Assert.IsFalse(req.Attributes.Any());
+		}
+
+		/// <summary>
+		/// Verifies the AddAttribute method.
+		/// </summary>
+		[TestMethod]
+		public void AddAttributeByValue() {
+			var req = new StoreRequest();
+			AttributeValues value = new AttributeValues();
+			req.AddAttribute(value);
+			Assert.AreSame(value, req.Attributes.Single());
+		}
+
+		/// <summary>
+		/// Verifies the AddAttribute method.
+		/// </summary>
+		[TestMethod]
+		public void AddAttributeByPrimitives() {
+			var req = new StoreRequest();
+			req.AddAttribute("http://att1", "value1", "value2");
+			AttributeValues value = req.Attributes.Single();
+			Assert.AreEqual("http://att1", value.TypeUri);
+			Assert.IsTrue(MessagingUtilities.AreEquivalent(new[] { "value1", "value2" }, value.Values));
+		}
+
+		/// <summary>
+		/// Verifies the Equals method.
+		/// </summary>
+		[TestMethod]
+		public void EqualityTests() {
+			var req1 = new StoreRequest();
+			var req2 = new StoreRequest();
+			Assert.AreEqual(req1, req2);
+
+			// Add attributes in different orders deliberately.
+			req1.AddAttribute("http://att1");
+			Assert.AreNotEqual(req1, req2);
+			req2.AddAttribute("http://att2");
+			Assert.AreNotEqual(req1, req2);
+			req1.AddAttribute("http://att2");
+			Assert.AreNotEqual(req1, req2);
+			req2.AddAttribute("http://att1");
+			Assert.AreEqual(req1, req2);
+		}
+	}
+}
diff --git a/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/StoreResponseTests.cs b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/StoreResponseTests.cs
new file mode 100644
index 0000000..5dab1b7
--- /dev/null
+++ b/src/DotNetOpenAuth.Test/OpenId/Extensions/AttributeExchange/StoreResponseTests.cs
@@ -0,0 +1,50 @@
+//-----------------------------------------------------------------------
+// <copyright file="StoreResponseTests.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.Test.OpenId.Extensions.AttributeExchange {
+	using DotNetOpenAuth.OpenId.Extensions.AttributeExchange;
+	using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+	[TestClass]
+	public class StoreResponseTests {
+		/// <summary>
+		/// Verifies the constructor's behavior.
+		/// </summary>
+		[TestMethod]
+		public void Ctor() {
+			var response = new StoreResponse();
+			Assert.IsTrue(response.Succeeded, "The default status should be Succeeded.");
+			Assert.IsNull(response.FailureReason);
+
+			response = new StoreResponse("failed");
+			Assert.IsFalse(response.Succeeded);
+			Assert.AreEqual("failed", response.FailureReason);
+		}
+
+		/// <summary>
+		/// Verifies the Equals method.
+		/// </summary>
+		[TestMethod]
+		public void EqualityTests() {
+			var response1 = new StoreResponse();
+			var response2 = new StoreResponse();
+			Assert.AreEqual(response1, response2);
+
+			response1.Succeeded = true;
+			response2.Succeeded = false;
+			Assert.AreNotEqual(response1, response2);
+
+			response1.Succeeded = false;
+			Assert.AreEqual(response1, response2);
+
+			response1.FailureReason = "bad code";
+			Assert.AreNotEqual(response1, response2);
+
+			response2.FailureReason = "bad code";
+			Assert.AreEqual(response1, response2);
+		}
+	}
+}
diff --git a/src/DotNetOpenAuth.Test/OpenId/Extensions/ExtensionTestBase.cs b/src/DotNetOpenAuth.Test/OpenId/Extensions/ExtensionTestUtilities.cs
index a052e55..a765d57 100644
--- a/src/DotNetOpenAuth.Test/OpenId/Extensions/ExtensionTestBase.cs
+++ b/src/DotNetOpenAuth.Test/OpenId/Extensions/ExtensionTestUtilities.cs
@@ -1,5 +1,5 @@
 //-----------------------------------------------------------------------
-// <copyright file="ExtensionTestBase.cs" company="Andrew Arnott">
+// <copyright file="ExtensionTestUtilities.cs" company="Andrew Arnott">
 //     Copyright (c) Andrew Arnott. All rights reserved.
 // </copyright>
 //-----------------------------------------------------------------------
@@ -17,6 +17,13 @@ namespace DotNetOpenAuth.Test.OpenId.Extensions {
 	using DotNetOpenAuth.Test.Messaging;
 
 	public static class ExtensionTestUtilities {
+		/// <summary>
+		/// Simulates an extension request and response.
+		/// </summary>
+		/// <remarks>
+		/// This method relies on the extension objects' Equals methods to verify
+		/// accurate transport.  The Equals methods should be verified by separate tests.
+		/// </remarks>
 		internal static void Roundtrip(
 			Protocol protocol,
 			IEnumerable<IOpenIdMessageExtension> requests,