Create unit tests for TestConnection

test/unit/ConnectionTest.cs

@@ -0,0 +1,46 @@
+using System;
+using System.DirectoryServices.Protocols;
+using CommonLibTest.Facades;
+using SharpHoundCommonLib;
+using SharpHoundCommonLib.Enums;
+using Xunit;
+
+namespace ConnectionTest
+{
+    public class ConnectionTests
+    {
+        [Fact]
+        public void TestConnectionNullResponse()
+        {
+            var connection = MockLdapConnection.Get(ResponseBehavior.NullResponse);
+            var testResponse = connection.TestConnection();
+
+            Assert.False(testResponse.Success);
+            Assert.Null(testResponse.Exception);
+        }
+
+        // This happens when a Kerberos misconfiguration occurs
+        [Fact]
+        public void TestConnectionEmptyResponse()
+        {
+            var connection = MockLdapConnection.Get(ResponseBehavior.EmptyResponse);
+            var testResponse = connection.TestConnection();
+
+            Assert.False(testResponse.Success);
+            Assert.IsType<LdapException>(testResponse.Exception);
+            Assert.Equal((int)LdapErrorCodes.KerberosAuthType, testResponse.Exception.ErrorCode);
+            Assert.Throws<ObjectDisposedException>(() => connection.Bind());
+        }
+
+        [Fact]
+        public void TestConnectionThrowsLdapException()
+        {
+            var connection = MockLdapConnection.Get(ResponseBehavior.ThrowsLdapException);
+            var testResponse = connection.TestConnection();
+
+            Assert.False(testResponse.Success);
+            Assert.IsType<LdapException>(testResponse.Exception);
+            Assert.Throws<ObjectDisposedException>(() => connection.Bind());
+        }
+    }
+}

test/unit/Facades/MockLdapConnection.cs

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+using System;
+using System.DirectoryServices.Protocols;
+using Moq;
+
+namespace CommonLibTest.Facades
+{
+    public static class MockLdapConnection
+    {
+        public static LdapConnection Get(ResponseBehavior responseBehavior)
+            => responseBehavior switch
+        {
+            ResponseBehavior.NullResponse => ReturnsNullResponse(),
+            ResponseBehavior.EmptyResponse => ReturnsEmptyResponse(),
+            ResponseBehavior.ThrowsLdapException => ThrowsLdapException(),
+            _ => throw new ArgumentOutOfRangeException(nameof(responseBehavior))
+        };
+
+        private static LdapConnection ReturnsNullResponse()
+        {
+            var mock = new Mock<LdapConnection>();
+            mock.Setup(x => x.SendRequest(It.IsAny<SearchRequest>()))
+                .Returns<SearchResponse>(null);
+            return mock.Object;
+        }
+
+        private static LdapConnection ReturnsEmptyResponse()
+        {
+            var mock = new Mock<LdapConnection>();
+            var emptyResponseMock = Mock.Of<SearchResponse>(m => m.Entries == Mock.Of<SearchResultEntryCollection>(m => m.Count == 0));
+            mock.Setup(x => x.SendRequest(It.IsAny<SearchRequest>()))
+                .Returns(emptyResponseMock);
+            return mock.Object;
+        }
+
+        private static LdapConnection ThrowsLdapException()
+        {
+            var mock = new Mock<LdapConnection>();
+            mock.Setup(x => x.SendRequest(It.IsAny<SearchRequest>()))
+                .Throws<LdapException>();
+            return mock.Object;
+        }
+    }
+
+    public enum ResponseBehavior
+    {
+        NullResponse,
+        EmptyResponse,
+        ThrowsLdapException,
+    }
+}