Tests | ActiveIssues (Part 4) (#3750)

* Reenable tests in SqlCommandCancelTest: TimeoutCancelTcp, TimeoutCancelNamedPipe, TimeoutDuringReadTcp, TimeoutDuringReadNamedPipe

* Reenable tests in SqlCredentialTest - SqlConnectionChangePasswordPlaintext, SqlConnectionChangePasswordSecureString

* Very light cleanup of SqlCredentialTest

* Reenable MarsSessionPoolingTest in MarsExecuteReader_Text_WithGC and MarsExecuteReader_StoredProcedure_WithGC

# Conflicts:
#	src/Microsoft.Data.SqlClient/tests/ManualTests/SQL/MARSSessionPoolingTest/MARSSessionPoolingTest.cs

* Split tests into separate tests for each scenario, discover which tests are flaky

* Mostly working . Except for those no close tests

* Clean up old code, but the nocloses test still breaks everything - need to investigate if it's a bug

* Clean up a biiiit more

* Finishing test matrix, improving DisposableArray, renaming test file to match guidelines

* Final iteration of tests, adding backoff to DMV queries, adding #nullable enable

* Fix mistakes in MARS tests

* Rewrite TimeoutCancel to use less custom utilities - hopefully this will make it easier to sort out why we have these failures

* Fix session => request comment

* Re-disable TimeoutCancelNamedPipe due to bug in managed SNI implementation

* Remove AreConnStringsNotAzureSynapse
Adding doc comments to DisposableArray

Author: benrr101

src/Microsoft.Data.SqlClient/tests/Common/DisposableArray.cs

@@ -0,0 +1,83 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections;
+using System.Collections.Generic;
+
+#nullable enable
+
+namespace Microsoft.Data.SqlClient.Tests.Common
+{
+    /// <summary>
+    /// Utility class that enables disposal of a collection of <see cref="IDisposable"/> objects
+    /// with a single <c>using</c> statement.
+    /// </summary>
+    /// <typeparam name="T">Type of the elements contained within.</typeparam>
+    public class DisposableArray<T> : IDisposable, IEnumerable<T>
+        where T : IDisposable?
+    {
+        private readonly T[] _elements;
+
+        /// <summary>
+        /// Constructs a new instance with <paramref name="size"/> elements.
+        /// </summary>
+        /// <remarks>
+        /// Remember when using this constructor that the underlying array will be initialized to
+        /// <c>default(T)</c>. If <typeparamref name="T"/> is a reference type, this will be
+        /// <c>null</c> - even if <typeparamref name="T"/> is not nullable!
+        /// </remarks>
+        /// <param name="size">Number of elements the new instance will contain.</param>
+        public DisposableArray(int size)
+        {
+            _elements = new T[size];
+        }
+
+        /// <summary>
+        /// Constructs a new instance from an existing array of elements.
+        /// </summary>
+        /// <param name="elements">Array of elements to store within the current instance.</param>
+        public DisposableArray(T[] elements)
+        {
+            _elements = elements;
+        }
+
+        /// <summary>
+        /// Gets or sets the element at index <see cref="i"/>.
+        /// </summary>
+        /// <param name="i">The element to get/set will be at this position in the array</param>
+        public T this[int i]
+        {
+            get => _elements[i];
+            set => _elements[i] = value;
+        }
+
+        /// <summary>
+        /// Gets the number of elements in the array.
+        /// </summary>
+        public int Length => _elements.Length;
+
+        /// <summary>
+        /// Disposes all elements in the current instance. Each element will be checked for
+        /// <c>null</c> before disposing it.
+        /// </summary>
+        public void Dispose()
+        {
+            foreach (T element in _elements)
+            {
+                element?.Dispose();
+            }
+
+            GC.SuppressFinalize(this);
+        }
+
+        /// <inheritdoc/>
+        public IEnumerator<T> GetEnumerator() =>
+            ((IEnumerable<T>)_elements).GetEnumerator();
+
+        /// <inheritdoc/>
+        IEnumerator IEnumerable.GetEnumerator() =>
+            _elements.GetEnumerator();
+    }
+}

src/Microsoft.Data.SqlClient/tests/ManualTests/Microsoft.Data.SqlClient.ManualTesting.Tests.csproj

@@ -181,7 +181,7 @@
     <Compile Include="SQL\KerberosTests\KerberosTest.cs" />
     <Compile Include="SQL\KerberosTests\KerberosTicketManager\KerberosTicketManager.cs" />
     <Compile Include="SQL\LocalDBTest\LocalDBTest.cs" />
-    <Compile Include="SQL\MARSSessionPoolingTest\MARSSessionPoolingTest.cs" />
+    <Compile Include="SQL\MARSSessionPoolingTest\MarsSessionPoolingTest.cs" />
     <Compile Include="SQL\MARSTest\MARSTest.cs" />
     <Compile Include="SQL\MirroringTest\ConnectionOnMirroringTest.cs" />
     <Compile Include="SQL\ParallelTransactionsTest\ParallelTransactionsTest.cs" />