Enable and fix performance analyzers

.editorconfig

@@ -150,6 +150,30 @@ dotnet_style_null_propagation = true
 # IDE0034: Simplify 'default' expression
 dotnet_diagnostic.IDE0034.severity = warning
 
+# IDE0090: Use 'new(...)'
+dotnet_diagnostic.IDE0090.severity = warning
+
+# IDE0150: Prefer 'null' check over type check
+dotnet_diagnostic.IDE0150.severity = warning
+
+# IDE0028: Simplify collection initialization
+dotnet_diagnostic.IDE0028.severity = warning
+
+# IDE0017: Simplify object initialization
+dotnet_diagnostic.IDE0017.severity = warning
+
+# CA1829: Use Length/Count property instead of Count() when available
+dotnet_diagnostic.CA1829.severity = warning
+
+# CA1840: Use 'Environment.CurrentManagedThreadId'
+dotnet_diagnostic.CA1840.severity = warning
+
+# CA1825: Avoid zero-length array allocations
+dotnet_diagnostic.CA1825.severity = warning
+
+# CA1854: Prefer the 'IDictionary.TryGetValue(TKey, out TValue)' method
+dotnet_diagnostic.CA1854.severity = warning
+
 #### Naming styles ####
 
 # Naming rules (define naming rule using dotnet_naming_rule.<rule_name>.<option>)
@@ -229,15 +253,3 @@ dotnet_naming_style.s_underscore_camel_case.required_prefix = s_
 dotnet_naming_style.s_underscore_camel_case.required_suffix =
 dotnet_naming_style.s_underscore_camel_case.word_separator =
 dotnet_naming_style.s_underscore_camel_case.capitalization = camel_case
-
-# IDE0090: Use 'new(...)'
-dotnet_diagnostic.IDE0090.severity = warning
-
-# IDE0150: Prefer 'null' check over type check
-dotnet_diagnostic.IDE0150.severity = warning
-
-# IDE0028: Simplify collection initialization
-dotnet_diagnostic.IDE0028.severity = warning
-
-# IDE0017: Simplify object initialization
-dotnet_diagnostic.IDE0017.severity = warning

Directory.Build.props

@@ -3,8 +3,17 @@
   <Import Project="scripts\build\TestFx.props" />
   <Import Project="eng\TFMConfiguration.props" />
 
+  <!-- Language configuration -->
   <PropertyGroup>
-    <LangVersion>Latest</LangVersion>
+    <!-- default to allowing all language features -->
+    <LangVersion>preview</LangVersion>
+    <!-- enable strict mode for Roslyn compiler -->
     <TreatWarningsAsErrors>True</TreatWarningsAsErrors>
+    <CodeAnalysisTreatWarningsAsErrors>true</CodeAnalysisTreatWarningsAsErrors>
+    <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
+    <EnableNETAnalyzers>true</EnableNETAnalyzers>
+    <!-- default to max warnlevel -->
+    <AnalysisLevel>preview</AnalysisLevel>
   </PropertyGroup>
+
 </Project>

src/Adapter/MSTest.TestAdapter/Discovery/AssemblyEnumerator.cs

@@ -370,10 +370,9 @@ private bool ProcessTestDataSourceTests(UnitTestElement test, MethodInfo methodI
                 discoveredTest.DisplayName = dataSource.GetDisplayName(methodInfo, d) ?? discoveredTest.DisplayName;
 
                 // if we have a duplicate test name don't expand the test, bail out.
-                if (discoveredTests.ContainsKey(discoveredTest.DisplayName))
+                if (discoveredTests.TryGetValue(discoveredTest.DisplayName, out var firstTestSeen))
                 {
-                    var firstSeen = discoveredIndex[discoveredTest.DisplayName];
-                    var warning = string.Format(CultureInfo.CurrentCulture, Resource.CannotExpandIDataSourceAttribute_DuplicateDisplayName, firstSeen, index, discoveredTest.DisplayName);
+                    var warning = string.Format(CultureInfo.CurrentCulture, Resource.CannotExpandIDataSourceAttribute_DuplicateDisplayName, firstTestSeen, index, discoveredTest.DisplayName);
                     warning = string.Format(CultureInfo.CurrentUICulture, Resource.CannotExpandIDataSourceAttribute, test.TestMethod.ManagedTypeName, test.TestMethod.ManagedMethodName, warning);
                     PlatformServiceProvider.Instance.AdapterTraceLogger.LogWarning($"DynamicDataEnumarator: {warning}");
 
@@ -388,7 +387,7 @@ private bool ProcessTestDataSourceTests(UnitTestElement test, MethodInfo methodI
                 }
                 catch (SerializationException)
                 {
-                    var firstSeen = discoveredIndex[discoveredTest.DisplayName];
+                    var firstIndexSeen = discoveredIndex[discoveredTest.DisplayName];
                     var warning = string.Format(CultureInfo.CurrentCulture, Resource.CannotExpandIDataSourceAttribute_CannotSerialize, index, discoveredTest.DisplayName);
                     warning = string.Format(CultureInfo.CurrentUICulture, Resource.CannotExpandIDataSourceAttribute, test.TestMethod.ManagedTypeName, test.TestMethod.ManagedMethodName, warning);
                     PlatformServiceProvider.Instance.AdapterTraceLogger.LogWarning($"DynamicDataEnumarator: {warning}");

src/Adapter/MSTest.TestAdapter/Execution/TestExecutionManager.cs

@@ -225,7 +225,7 @@ private void ExecuteTestsInSource(IEnumerable<TestCase> tests, IRunContext runCo
         PlatformServiceProvider.Instance.AdapterTraceLogger.LogInfo("Created unit-test runner {0}", source);
 
         // Default test set is filtered tests based on user provided filter criteria
-        ICollection<TestCase> testsToRun = new TestCase[0];
+        ICollection<TestCase> testsToRun = Array.Empty<TestCase>();
         var filterExpression = TestMethodFilter.GetFilterExpression(runContext, frameworkHandle, out var filterHasError);
         if (filterHasError)
         {

src/Adapter/MSTest.TestAdapter/Execution/TestMethodInfo.cs

@@ -770,6 +770,6 @@ void executeAsyncAction()
 
     private static class EmptyHolder<T>
     {
-        internal static readonly T[] Array = new T[0];
+        internal static readonly T[] Array = System.Array.Empty<T>();
     }
 }

src/Adapter/MSTest.TestAdapter/Helpers/DictionaryHelper.cs

@@ -40,6 +40,7 @@ public static IDictionary<TKey, TValue> ConcatWithOverwrites<TKey, TValue>(
         var overwrites = new List<TKey>();
         foreach (var k in overwrite.Keys)
         {
+#pragma warning disable CA1854 // Prefer the 'IDictionary.TryGetValue(TKey, out TValue)' method | False-positive
             if (destination.ContainsKey(k))
             {
                 PlatformServiceProvider.Instance.AdapterTraceLogger.LogInfo("DictionaryHelper.ConcatWithOverwrites: The {0} already contains key {1}. Overwriting it with value from {2}.", sourceFriendlyName, k, overwriteFriendlyName);
@@ -51,6 +52,7 @@ public static IDictionary<TKey, TValue> ConcatWithOverwrites<TKey, TValue>(
                 PlatformServiceProvider.Instance.AdapterTraceLogger.LogInfo("DictionaryHelper.ConcatWithOverwrites: The {0} does not contain key {1}. Adding it from {2}.", sourceFriendlyName, k, overwriteFriendlyName);
                 destination.Add(k, overwrite[k]);
             }
+#pragma warning restore CA1854 // Prefer the 'IDictionary.TryGetValue(TKey, out TValue)' method
         }
 
         PlatformServiceProvider.Instance.AdapterTraceLogger.LogInfo("DictionaryHelper.ConcatWithOverwrites: Merging done: Resulting dictionary has keys {0}, overwrites {1}.", string.Join(", ", destination.Keys), string.Join(", ", overwrites));

src/Adapter/PlatformServices/Deployment/AssemblyLoadWorker.cs

@@ -59,7 +59,7 @@ public string[] GetFullPathToDependentAssemblies(string assemblyPath, out IList<
             EqtTrace.Error(ex);
 
             warnings.Add(ex.Message);
-            return new string[0]; // Otherwise just return no dependencies.
+            return Array.Empty<string>(); // Otherwise just return no dependencies.
         }
 
         Debug.Assert(assembly != null, "assembly");
@@ -168,7 +168,7 @@ private void ProcessChildren(Assembly assembly, IList<string> result, ISet<strin
         }
 
         // Take care of .netmodule's.
-        var modules = new Module[0];
+        var modules = Array.Empty<Module>();
         try
         {
             EqtTrace.Verbose($"AssemblyLoadWorker.GetFullPathToDependentAssemblies: Getting modules of {assembly.FullName}.");

src/Adapter/PlatformServices/Services/TestDataSource.cs

@@ -57,9 +57,10 @@ IEnumerable<object> ITestDataSource.GetData(UTF.ITestMethod testMethodInfo, ITes
         {
             GetConnectionProperties(testMethodInfo.GetAttributes<UTF.DataSourceAttribute>(false)[0], out providerNameInvariant, out connectionString, out tableName, out dataAccessMethod);
         }
-        catch (Exception ex)
+        catch
         {
-            throw ex;
+            // REVIEW ME: @Haplois, was there any good reason to mess up stack trace?
+            throw;
         }
 
         try

src/TestFramework/MSTest.Core/Assertions/StringAssert.cs

@@ -12,7 +12,7 @@ namespace Microsoft.VisualStudio.TestTools.UnitTesting;
 /// </summary>
 public sealed class StringAssert
 {
-    private static readonly object[] Empty = new object[0];
+    private static readonly object[] Empty = Array.Empty<object>();
 
     private static StringAssert s_that;
 

src/TestFramework/MSTest.Core/Attributes/DataSource/DataRowAttribute.cs

@@ -20,7 +20,7 @@ public class DataRowAttribute : Attribute, ITestDataSource
     /// </summary>
     public DataRowAttribute()
     {
-        Data = new object[0];
+        Data = Array.Empty<object>();
     }
 
     /// <summary>

test/E2ETests/DiscoveryAndExecutionTests/Extensions/AssertionExtensions.cs

@@ -100,7 +100,7 @@ private static void ContainsExpectedTestsWithOutcome(IEnumerable<TestResult> out
     {
         if (matchCount)
         {
-            var expectedCount = expectedTests.Count();
+            var expectedCount = expectedTests.Length;
             AssertOutcomeCount(outcomedTests, expectedOutcome, expectedCount);
         }
 

test/UnitTests/MSTest.Core.Unit.Tests/Attributes/DataRowAttributeTests.cs

@@ -25,7 +25,7 @@ public void DefaultConstructorSetsEmptyArrayPassed()
     {
         var dataRow = new DataRowAttribute();
 
-        CollectionAssert.AreEqual(new object[] { }, dataRow.Data);
+        CollectionAssert.AreEqual(System.Array.Empty<object>(), dataRow.Data);
     }
 
     [TestMethod]

test/UnitTests/MSTest.Core.Unit.Tests/Attributes/DynamicDataAttributeTests.cs

@@ -310,7 +310,7 @@ public static IEnumerable<object[]> EmptyProperty
     {
         get
         {
-            return new object[][] { };
+            return Array.Empty<object[]>();
         }
     }
 

test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Discovery/AssemblyEnumeratorTests.cs

@@ -405,13 +405,13 @@ private static Mock<TestableAssembly> CreateMockTestableAssembly()
             .Setup(a => a.GetCustomAttributes(
                 typeof(FrameworkV2::Microsoft.VisualStudio.TestTools.UnitTesting.DiscoverInternalsAttribute),
                 true))
-            .Returns(new Attribute[0]);
+            .Returns(Array.Empty<Attribute>());
 
         mockAssembly
             .Setup(a => a.GetCustomAttributes(
                 typeof(FrameworkV2::Microsoft.VisualStudio.TestTools.UnitTesting.TestDataSourceDiscoveryAttribute),
                 true))
-            .Returns(new Attribute[0]);
+            .Returns(Array.Empty<Attribute>());
 
         return mockAssembly;
     }

test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Discovery/TypeEnumeratorTests.cs

@@ -453,7 +453,7 @@ public void GetTestFromMethodShouldSetWorkItemIdsToNullIfNotAny()
         SetupTestClassAndTestMethods(isValidTestClass: true, isValidTestMethod: true, isMethodFromSameAssembly: true);
         TypeEnumerator typeEnumerator = GetTypeEnumeratorInstance(typeof(DummyTestClass), "DummyAssemblyName");
         var methodInfo = typeof(DummyTestClass).GetMethod("MethodWithVoidReturnType");
-        _mockReflectHelper.Setup(rh => rh.GetCustomAttributes(methodInfo, typeof(UTF.WorkItemAttribute))).Returns(new Attribute[0]);
+        _mockReflectHelper.Setup(rh => rh.GetCustomAttributes(methodInfo, typeof(UTF.WorkItemAttribute))).Returns(Array.Empty<Attribute>());
 
         var testElement = typeEnumerator.GetTestFromMethod(methodInfo, true, _warnings);
 

test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Execution/TestExecutionManagerTests.cs

@@ -972,15 +972,15 @@ public void TestMethod1()
         {
             // Ensures stability.. for the thread to be not used for another test method
             System.Threading.Thread.Sleep(2000);
-            ThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            ThreadIds.Add(Environment.CurrentManagedThreadId);
         }
 
         [UTF.TestMethod]
         public void TestMethod2()
         {
             // Ensures stability.. for the thread to be not used for another test method
             System.Threading.Thread.Sleep(2000);
-            ThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            ThreadIds.Add(Environment.CurrentManagedThreadId);
         }
     }
 
@@ -999,15 +999,15 @@ public void TestMethod1()
         {
             // Ensures stability.. for the thread to be not used for another test method
             System.Threading.Thread.Sleep(2000);
-            ThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            ThreadIds.Add(Environment.CurrentManagedThreadId);
         }
 
         [UTF.TestMethod]
         public void TestMethod2()
         {
             // Ensures stability.. for the thread to be not used for another test method
             System.Threading.Thread.Sleep(2000);
-            ThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            ThreadIds.Add(Environment.CurrentManagedThreadId);
         }
     }
 
@@ -1026,7 +1026,7 @@ public void TestMethod1()
         {
             // Ensures stability.. for the thread to be not used for another test method
             Thread.Sleep(2000);
-            ThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            ThreadIds.Add(Environment.CurrentManagedThreadId);
         }
     }
 
@@ -1058,7 +1058,7 @@ public void TestMethod1()
         {
             // Ensures stability.. for the thread to be not used for another test method
             Thread.Sleep(2000);
-            ParallelizableTestsThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            ParallelizableTestsThreadIds.Add(Environment.CurrentManagedThreadId);
             ThreadApartmentStates.Add(Thread.CurrentThread.GetApartmentState());
 
             LastParallelizableTestRun = DateTime.Now;
@@ -1069,7 +1069,7 @@ public void TestMethod2()
         {
             // Ensures stability.. for the thread to be not used for another test method
             Thread.Sleep(2000);
-            ParallelizableTestsThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            ParallelizableTestsThreadIds.Add(Environment.CurrentManagedThreadId);
             ThreadApartmentStates.Add(Thread.CurrentThread.GetApartmentState());
 
             LastParallelizableTestRun = DateTime.Now;
@@ -1084,7 +1084,7 @@ public void TestMethod3()
                 FirstUnParallelizableTestRun = DateTime.Now;
             }
 
-            UnParallelizableTestsThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            UnParallelizableTestsThreadIds.Add(Environment.CurrentManagedThreadId);
             ThreadApartmentStates.Add(Thread.CurrentThread.GetApartmentState());
         }
 
@@ -1097,7 +1097,7 @@ public void TestMethod4()
                 FirstUnParallelizableTestRun = DateTime.Now;
             }
 
-            UnParallelizableTestsThreadIds.Add(Thread.CurrentThread.ManagedThreadId);
+            UnParallelizableTestsThreadIds.Add(Environment.CurrentManagedThreadId);
             ThreadApartmentStates.Add(Thread.CurrentThread.GetApartmentState());
         }
     }

test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Execution/TestMethodInfoTests.cs

@@ -1398,7 +1398,7 @@ public void ResolveArgumentsShouldReturnEmptyParamsWithNoneProvided()
             _testMethodOptions);
 
         object[] arguments = new object[] { 1 };
-        object[] expectedArguments = new object[] { 1, new string[] { } };
+        object[] expectedArguments = new object[] { 1, Array.Empty<string>() };
         var resolvedArguments = method.ResolveArguments(arguments);
 
         Assert.AreEqual(2, resolvedArguments.Length);

test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Execution/TypeCacheTests.cs

@@ -1183,7 +1183,7 @@ public void GetTestMethodInfoShouldNotAddDuplicateTestPropertiesToTestContext()
     public void GetTestMethodInfoShouldReturnTestMethodInfoForDerivedTestClasses()
     {
         var type = typeof(DerivedTestClass);
-        var methodInfo = type.GetRuntimeMethod("DummyTestMethod", new Type[] { });
+        var methodInfo = type.GetRuntimeMethod("DummyTestMethod", Array.Empty<Type>());
         var testMethod = new TestMethod(methodInfo.Name, type.FullName, "A", isAsync: false);
 
         var testMethodInfo = _typeCache.GetTestMethodInfo(
@@ -1201,7 +1201,7 @@ public void GetTestMethodInfoShouldReturnTestMethodInfoForDerivedTestClasses()
     public void GetTestMethodInfoShouldReturnTestMethodInfoForDerivedClassMethodOverloadByDefault()
     {
         var type = typeof(DerivedTestClass);
-        var methodInfo = type.GetRuntimeMethod("OverloadedTestMethod", new Type[] { });
+        var methodInfo = type.GetRuntimeMethod("OverloadedTestMethod", Array.Empty<Type>());
         var testMethod = new TestMethod(methodInfo.Name, type.FullName, "A", isAsync: false);
 
         var testMethodInfo = _typeCache.GetTestMethodInfo(
@@ -1220,7 +1220,7 @@ public void GetTestMethodInfoShouldReturnTestMethodInfoForDeclaringTypeMethodOve
     {
         var baseType = typeof(BaseTestClass);
         var type = typeof(DerivedTestClass);
-        var methodInfo = baseType.GetRuntimeMethod("OverloadedTestMethod", new Type[] { });
+        var methodInfo = baseType.GetRuntimeMethod("OverloadedTestMethod", Array.Empty<Type>());
         var testMethod = new TestMethod(methodInfo.Name, type.FullName, "A", isAsync: false)
         {
             DeclaringClassFullName = baseType.FullName

test/UnitTests/MSTest.CoreAdapter.Unit.Tests/ObjectModel/UnitTestElementTests.cs

@@ -129,7 +129,7 @@ public void ToTestCaseShouldSetTestCategoryIfPresent()
 
         Assert.IsNull(testCase.GetPropertyValue(Constants.TestCategoryProperty));
 
-        _unitTestElement.TestCategory = new string[] { };
+        _unitTestElement.TestCategory = Array.Empty<string>();
         testCase = _unitTestElement.ToTestCase();
 
         Assert.IsNull(testCase.GetPropertyValue(Constants.TestCategoryProperty));
@@ -195,7 +195,7 @@ public void ToTestCaseShouldSetDeploymentItemPropertyIfPresent()
 
         Assert.IsNull(testCase.GetPropertyValue(Constants.DeploymentItemsProperty));
 
-        _unitTestElement.DeploymentItems = new KeyValuePair<string, string>[] { };
+        _unitTestElement.DeploymentItems = Array.Empty<KeyValuePair<string, string>>();
         testCase = _unitTestElement.ToTestCase();
 
         Assert.IsNull(testCase.GetPropertyValue(Constants.DeploymentItemsProperty));

test/UnitTests/MSTest.CoreAdapter.Unit.Tests/TestableImplementations/TestableReflectHelper.cs

@@ -45,9 +45,9 @@ internal override Attribute[] GetCustomAttributeForAssembly(MemberInfo memberInf
     {
         var hashcode = MemberTypes.All.GetHashCode() + type.FullName.GetHashCode();
 
-        if (_customAttributes.ContainsKey(hashcode))
+        if (_customAttributes.TryGetValue(hashcode, out Attribute[] value))
         {
-            return _customAttributes[hashcode];
+            return value;
         }
         else
         {
@@ -59,9 +59,9 @@ internal override Attribute[] GetCustomAttributes(MemberInfo memberInfo, Type ty
     {
         var hashcode = memberInfo.MemberType.GetHashCode() + type.FullName.GetHashCode();
 
-        if (_customAttributes.ContainsKey(hashcode))
+        if (_customAttributes.TryGetValue(hashcode, out Attribute[] value))
         {
-            return _customAttributes[hashcode];
+            return value;
         }
         else
         {

test/UnitTests/PlatformServices.Desktop.Unit.Tests/Deployment/AssemblyLoadWorkerTests.cs

@@ -138,7 +138,7 @@ public override AssemblyName[] GetReferencedAssemblies()
                 return GetReferencedAssembliesSetter.Invoke();
             }
 
-            return new AssemblyName[] { };
+            return Array.Empty<AssemblyName>();
         }
 
         public string Name
@@ -177,7 +177,7 @@ public override string Location
 
         public override Module[] GetModules(bool getResourceModules)
         {
-            return new Module[] { };
+            return Array.Empty<Module>();
         }
     }