use some collection expressions

shared/NullableAttributes.cs

@@ -96,7 +96,7 @@ internal sealed class MemberNotNullAttribute : Attribute
     /// <param name="member">
     /// The field or property member that is promised to be not-null.
     /// </param>
-    public MemberNotNullAttribute(string member) => Members = new[] { member };
+    public MemberNotNullAttribute(string member) => Members = [member];
 
     /// <summary>Initializes the attribute with the list of field and property members.</summary>
     /// <param name="members">
@@ -122,7 +122,7 @@ internal sealed class MemberNotNullWhenAttribute : Attribute
     public MemberNotNullWhenAttribute(bool returnValue, string member)
     {
         ReturnValue = returnValue;
-        Members = new[] { member };
+        Members = [member];
     }
 
     /// <summary>Initializes the attribute with the specified return value condition and list of field and property members.</summary>

src/DataCollectors/Microsoft.TestPlatform.Extensions.EventLogCollector/EventLogDataCollector.cs

@@ -326,7 +326,7 @@ protected override void Dispose(bool disposing)
     private static ISet<string> ParseCommaSeparatedList(string commaSeparatedList)
     {
         ISet<string> strings = new HashSet<string>();
-        string[] items = commaSeparatedList.Split(new char[] { ',' });
+        string[] items = commaSeparatedList.Split([',']);
         foreach (string item in items)
         {
             strings.Add(item.Trim());

src/Microsoft.TestPlatform.Build/Tasks/VSTestTask2.cs

@@ -48,7 +48,7 @@ public class VSTestTask2 : ToolTask, ITestTask
     protected override Encoding StandardOutputEncoding => _disableUtf8ConsoleEncoding ? base.StandardOutputEncoding : Encoding.UTF8;
 
     private readonly string _messageSplitter = "||||";
-    private readonly string[] _messageSplitterArray = new[] { "||||" };
+    private readonly string[] _messageSplitterArray = ["||||"];
     private readonly string _ansiReset = "\x1b[39;49m";
 
     private readonly bool _disableUtf8ConsoleEncoding;
@@ -266,7 +266,7 @@ private bool TryGetMessage(string singleLine, out string name, out string?[] dat
         }
 
         name = string.Empty;
-        data = Array.Empty<string>();
+        data = [];
         return false;
     }
 

src/Microsoft.TestPlatform.Client/DesignMode/DesignModeClient.cs

@@ -334,7 +334,7 @@ public int LaunchCustomHost(TestProcessStartInfo testProcessStartInfo, Cancellat
             // Even if TP has a timeout here, there is no way TP can abort or stop the thread/task that is hung in IDE or LUT
             // Even if TP can abort the API somehow, TP is essentially putting IDEs or Clients in inconsistent state without having info on
             // Since the IDEs own user-UI-experience here, TP will let the custom host launch as much time as IDEs define it for their users
-            WaitHandle.WaitAny(new WaitHandle[] { waitHandle, cancellationToken.WaitHandle });
+            WaitHandle.WaitAny([waitHandle, cancellationToken.WaitHandle]);
 
             cancellationToken.ThrowTestPlatformExceptionIfCancellationRequested();
 
@@ -387,7 +387,7 @@ public bool AttachDebuggerToProcess(AttachDebuggerInfo attachDebuggerInfo, Cance
                 _communicationManager.SendMessage(MessageType.EditorAttachDebugger2, payload);
             }
 
-            WaitHandle.WaitAny(new WaitHandle[] { waitHandle, cancellationToken.WaitHandle });
+            WaitHandle.WaitAny([waitHandle, cancellationToken.WaitHandle]);
 
             cancellationToken.ThrowTestPlatformExceptionIfCancellationRequested();
             onAttachDebuggerAckRecieved = null;

src/Microsoft.TestPlatform.Client/TestPlatform.cs

@@ -283,7 +283,7 @@ private static void AddExtensionAssembliesFromExtensionDirectory()
         TestAdapterLoadingStrategy strategy = runConfiguration.TestAdapterLoadingStrategy;
 
         FileHelper fileHelper = new();
-        IEnumerable<string> defaultExtensionPaths = Enumerable.Empty<string>();
+        IEnumerable<string> defaultExtensionPaths = [];
 
         // Explicit adapter loading
         if (strategy.HasFlag(TestAdapterLoadingStrategy.Explicit))
@@ -354,7 +354,7 @@ private static IEnumerable<string> ExpandAdaptersWithExplicitStrategy(string pat
     {
         if (!strategy.HasFlag(TestAdapterLoadingStrategy.Explicit))
         {
-            return Enumerable.Empty<string>();
+            return [];
         }
 
         if (fileHelper.Exists(path))
@@ -377,7 +377,7 @@ private static IEnumerable<string> ExpandAdaptersWithExplicitStrategy(string pat
         }
 
         EqtTrace.Warning($"{nameof(TestPlatform)}.{nameof(ExpandAdaptersWithExplicitStrategy)} AdapterPath Not Found: {path}");
-        return Enumerable.Empty<string>();
+        return [];
     }
 
     private static IEnumerable<string> ExpandAdaptersWithDefaultStrategy(string path, IFileHelper fileHelper)
@@ -388,7 +388,7 @@ private static IEnumerable<string> ExpandAdaptersWithDefaultStrategy(string path
         {
             EqtTrace.Warning($"{nameof(TestPlatform)}.{nameof(ExpandAdaptersWithDefaultStrategy)} AdapterPath Not Found: {path}");
 
-            return Enumerable.Empty<string>();
+            return [];
         }
 
         return fileHelper.EnumerateFiles(

src/Microsoft.TestPlatform.Common/ExtensionFramework/VSExtensionManager.cs

@@ -85,7 +85,7 @@ private IEnumerable<string> GetTestExtensionsInternal(string extensionType)
         var resolutionPaths = installContext.GetVisualStudioCommonLocations(vsInstallPath);
         using (var assemblyResolver = new AssemblyResolver(resolutionPaths))
         {
-            var settingsManager = SettingsManagerType.GetMethod("CreateForApplication", new Type[] { typeof(string) })?.Invoke(null, new object[] { installContext.GetVisualStudioPath(vsInstallPath) });
+            var settingsManager = SettingsManagerType.GetMethod("CreateForApplication", [typeof(string)])?.Invoke(null, [installContext.GetVisualStudioPath(vsInstallPath)]);
             if (settingsManager == null)
             {
                 EqtTrace.Warning("VSExtensionManager : Unable to create settings manager");
@@ -99,8 +99,8 @@ private IEnumerable<string> GetTestExtensionsInternal(string extensionType)
 
                 if (extensionManager != null)
                 {
-                    installedExtensions = ExtensionManagerServiceType.GetMethod("GetEnabledExtensionContentLocations", new Type[] { typeof(string) })?.Invoke(
-                        extensionManager, new object[] { extensionType }) as IEnumerable<string>;
+                    installedExtensions = ExtensionManagerServiceType.GetMethod("GetEnabledExtensionContentLocations", [typeof(string)])?.Invoke(
+                        extensionManager, [extensionType]) as IEnumerable<string>;
                 }
                 else
                 {

src/Microsoft.TestPlatform.Common/Filtering/FilterExpression.cs

@@ -122,7 +122,7 @@ private static void ProcessOperator(Stack<FilterExpression> filterStack, Operato
         if (null == properties)
         {
             // if null, initialize to empty list so that invalid properties can be found.
-            properties = Enumerable.Empty<string>();
+            properties = [];
         }
 
         return IterateFilterExpression<string[]?>((current, result) =>
@@ -132,7 +132,7 @@ private static void ProcessOperator(Stack<FilterExpression> filterStack, Operato
             {
                 var valid = current._condition.ValidForProperties(properties, propertyProvider);
                 // If it's not valid will add it to the function's return array.
-                return !valid ? new string[1] { current._condition.Name } : null;
+                return !valid ? [current._condition.Name] : null;
             }
 
             // Concatenate the children node's result to get their parent result.

src/Microsoft.TestPlatform.Common/Utilities/AssemblyResolver.cs

@@ -40,7 +40,7 @@ internal class AssemblyResolver : IDisposable
 
     private readonly IAssemblyLoadContext _platformAssemblyLoadContext;
 
-    private static readonly string[] SupportedFileExtensions = { ".dll", ".exe" };
+    private static readonly string[] SupportedFileExtensions = [".dll", ".exe"];
 
     /// <summary>
     /// Initializes a new instance of the <see cref="AssemblyResolver"/> class.

src/Microsoft.TestPlatform.Common/Utilities/FakesUtilities.cs

@@ -231,7 +231,7 @@ private static void EnsureSettingsNode(XmlDocument settings, TestRunSettings set
         {
             var assembly = LoadTestPlatformAssembly();
             var type = assembly?.GetType(ConfiguratorAssemblyQualifiedName, false);
-            var method = type?.GetMethod(NetFrameworkConfiguratorMethodName, new Type[] { typeof(IEnumerable<string>) });
+            var method = type?.GetMethod(NetFrameworkConfiguratorMethodName, [typeof(IEnumerable<string>)]);
             if (method != null)
             {
                 return (Func<IEnumerable<string>, string>)method.CreateDelegate(typeof(Func<IEnumerable<string>, string>));
@@ -251,7 +251,7 @@ private static void EnsureSettingsNode(XmlDocument settings, TestRunSettings set
         {
             var assembly = LoadTestPlatformAssembly();
             var type = assembly?.GetType(ConfiguratorAssemblyQualifiedName, false, false);
-            var method = type?.GetMethod(CrossPlatformConfiguratorMethodName, new Type[] { typeof(IDictionary<string, FrameworkVersion>) });
+            var method = type?.GetMethod(CrossPlatformConfiguratorMethodName, [typeof(IDictionary<string, FrameworkVersion>)]);
             if (method != null)
             {
                 return (Func<IDictionary<string, FrameworkVersion>, DataCollectorSettings>)method.CreateDelegate(typeof(Func<IDictionary<string, FrameworkVersion>, DataCollectorSettings>));

src/Microsoft.TestPlatform.Common/Utilities/InstallationContext.cs

@@ -48,13 +48,13 @@ public string GetVisualStudioPath(string visualStudioDirectory)
     [SuppressMessage("Performance", "CA1822:Mark members as static", Justification = "Part of the public API")]
     public string[] GetVisualStudioCommonLocations(string visualStudioDirectory)
     {
-        return new[]
-        {
+        return
+        [
             Path.Combine(visualStudioDirectory, PrivateAssembliesDirName),
             Path.Combine(visualStudioDirectory, PublicAssembliesDirName),
             Path.Combine(visualStudioDirectory, "CommonExtensions", "Microsoft", "TestWindow"),
             Path.Combine(visualStudioDirectory, "CommonExtensions", "Microsoft", "TeamFoundation", "Team Explorer"),
             visualStudioDirectory
-        };
+        ];
     }
 }

src/Microsoft.TestPlatform.Common/Utilities/MetadataReaderHelper.cs

@@ -42,7 +42,7 @@ internal static class MetadataReaderExtensionsHelper
 {
     private const string TestExtensionTypesAttributeV2 = "Microsoft.VisualStudio.TestPlatform.TestExtensionTypesV2Attribute";
     private static readonly ConcurrentDictionary<string, Type[]> AssemblyCache = new();
-    private static readonly Type[] EmptyTypeArray = new Type[0];
+    private static readonly Type[] EmptyTypeArray = [];
 
     public static Type[] DiscoverTestExtensionTypesV2Attribute(Assembly loadedAssembly, string assemblyFilePath)
         => AssemblyCache.GetOrAdd(assemblyFilePath, DiscoverTestExtensionTypesV2AttributeInternal(loadedAssembly, assemblyFilePath));

src/Microsoft.TestPlatform.Common/Utilities/RunSettingsUtilities.cs

@@ -4,7 +4,6 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
-using System.Linq;
 
 using Microsoft.VisualStudio.TestPlatform.ObjectModel;
 using Microsoft.VisualStudio.TestPlatform.ObjectModel.Utilities;
@@ -176,12 +175,12 @@ public static IEnumerable<string> GetTestAdaptersPaths(string? runSettings)
     {
         var runConfiguration = XmlRunSettingsUtilities.GetRunConfigurationNode(runSettings);
 
-        IEnumerable<string> testAdaptersPaths = Enumerable.Empty<string>();
+        IEnumerable<string> testAdaptersPaths = [];
         if (runConfiguration != null)
         {
             if (runConfiguration.TestAdaptersPathsSet)
             {
-                testAdaptersPaths = runConfiguration.TestAdaptersPaths.Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries);
+                testAdaptersPaths = runConfiguration.TestAdaptersPaths.Split([';'], StringSplitOptions.RemoveEmptyEntries);
             }
         }
 

src/Microsoft.TestPlatform.CommunicationUtilities/Serialization/TestObjectConverter.cs

@@ -102,12 +102,12 @@ internal class TestObjectConverter7 : JsonConverter
 {
     // Empty is not present everywhere
 #pragma warning disable CA1825 // Avoid zero-length array allocations
-    private static readonly object[] EmptyObjectArray = new object[0];
+    private static readonly object[] EmptyObjectArray = [];
 #pragma warning restore CA1825 // Avoid zero-length array allocations
 
     public TestObjectConverter7()
     {
-        TestPropertyCtor = typeof(TestProperty).GetConstructor(BindingFlags.NonPublic | BindingFlags.Instance, null, new Type[0], null);
+        TestPropertyCtor = typeof(TestProperty).GetConstructor(BindingFlags.NonPublic | BindingFlags.Instance, null, [], null);
     }
 
     /// <inheritdoc/>

src/Microsoft.TestPlatform.CommunicationUtilities/TestRequestSender.cs

@@ -217,7 +217,7 @@ public bool WaitForRequestHandlerConnection(int connectionTimeout, CancellationT
         // Wait until either connection is successful, handled by connected.WaitHandle
         // or operation is canceled, handled by cancellationToken.WaitHandle
         // or testhost exits unexpectedly, handled by clientExited.WaitHandle
-        var waitIndex = WaitHandle.WaitAny(new WaitHandle[] { _connected.WaitHandle, cancellationToken.WaitHandle, _clientExited.WaitHandle }, connectionTimeout);
+        var waitIndex = WaitHandle.WaitAny([_connected.WaitHandle, cancellationToken.WaitHandle, _clientExited.WaitHandle], connectionTimeout);
 
         EqtTrace.Verbose("TestRequestSender.WaitForRequestHandlerConnection: waiting took {0} ms, with timeout {1} ms, and result {2}, which is {3}.", sw.ElapsedMilliseconds, connectionTimeout, waitIndex, waitIndex == 0 ? "success" : "failure");
 

src/Microsoft.TestPlatform.CoreUtilities/Helpers/FileHelper.cs

@@ -50,7 +50,7 @@ public IEnumerable<string> EnumerateFiles(
     {
         if (endsWithSearchPatterns == null || endsWithSearchPatterns.Length == 0)
         {
-            return Enumerable.Empty<string>();
+            return [];
         }
 
         var files = Directory.EnumerateFiles(directory, "*", searchOption);

src/Microsoft.TestPlatform.CrossPlatEngine/AttachmentsProcessing/DataCollectorAttachmentProcessorAppDomain.cs

@@ -63,7 +63,7 @@ public DataCollectorAttachmentProcessorAppDomain(InvokedDataCollector invokedDat
             false,
             BindingFlags.Default,
             null,
-            new[] { _pipeShutdownMessagePrefix },
+            [_pipeShutdownMessagePrefix],
             null,
             null);
 

src/Microsoft.TestPlatform.CrossPlatEngine/Client/InProcessProxyDiscoveryManager.cs

@@ -74,7 +74,7 @@ public void DiscoverTests(DiscoveryCriteria discoveryCriteria, ITestDiscoveryEve
 
                 var discoveryCompeleteEventsArg = new DiscoveryCompleteEventArgs(-1, true);
 
-                eventHandler.HandleDiscoveryComplete(discoveryCompeleteEventsArg, Enumerable.Empty<TestCase>());
+                eventHandler.HandleDiscoveryComplete(discoveryCompeleteEventsArg, []);
             }
         });
     }
@@ -103,15 +103,15 @@ public void Abort(ITestDiscoveryEventsHandler2 eventHandler)
 
     private void InitializeExtensions(IEnumerable<string> sources)
     {
-        var extensionsFromSource = _testHostManager.GetTestPlatformExtensions(sources, Enumerable.Empty<string>());
+        var extensionsFromSource = _testHostManager.GetTestPlatformExtensions(sources, []);
         if (extensionsFromSource.Any())
         {
             TestPluginCache.Instance.UpdateExtensions(extensionsFromSource, false);
         }
 
         // We don't need to pass list of extension as we are running inside vstest.console and
         // it will use TestPluginCache of vstest.console
-        _discoveryManager.Initialize(Enumerable.Empty<string>(), null);
+        _discoveryManager.Initialize([], null);
     }
 
     public void InitializeDiscovery(DiscoveryCriteria discoveryCriteria, ITestDiscoveryEventsHandler2 eventHandler, bool skipDefaultAdapters)

src/Microsoft.TestPlatform.CrossPlatEngine/Client/InProcessProxyexecutionManager.cs

@@ -135,15 +135,15 @@ public void Close()
 
     private void InitializeExtensions(IEnumerable<string> sources)
     {
-        var extensionsFromSource = _testHostManager.GetTestPlatformExtensions(sources, Enumerable.Empty<string>());
+        var extensionsFromSource = _testHostManager.GetTestPlatformExtensions(sources, []);
         if (extensionsFromSource.Any())
         {
             TestPluginCache.Instance.UpdateExtensions(extensionsFromSource, false);
         }
 
         // We don't need to pass list of extension as we are running inside vstest.console and
         // it will use TestPluginCache of vstest.console
-        _executionManager.Initialize(Enumerable.Empty<string>(), null);
+        _executionManager.Initialize([], null);
     }
 
     public void InitializeTestRun(TestRunCriteria testRunCriteria, IInternalTestRunEventsHandler eventHandler)

src/Microsoft.TestPlatform.CrossPlatEngine/Client/Parallel/ParallelOperationManager.cs

@@ -312,7 +312,7 @@ private void ClearCompletedSlot(TManager completedManager)
 
     private static string GetSourcesForSlotExpensive(ParallelOperationManager<TManager, TEventHandler, TWorkload>.Slot slot)
     {
-        return string.Join(", ", (slot.Work as DiscoveryCriteria)?.Sources ?? (slot.Work as TestRunCriteria)?.Sources ?? Array.Empty<string>());
+        return string.Join(", ", (slot.Work as DiscoveryCriteria)?.Sources ?? (slot.Work as TestRunCriteria)?.Sources ?? []);
     }
 
     public void DoActionOnAllManagers(Action<TManager> action, bool doActionsInParallel = false)

src/Microsoft.TestPlatform.CrossPlatEngine/Client/Parallel/ParallelProxyDiscoveryManager.cs

@@ -222,7 +222,7 @@ private List<ProviderSpecificWorkload<DiscoveryCriteria>> SplitToWorkloads(Disco
             if (!_isParallel && testhostProviderInfo.Shared)
             {
                 // Create one big source batch that will be single workload for single testhost.
-                sourceBatches = new List<string[]> { group.Select(w => w.Work).ToArray() };
+                sourceBatches = [group.Select(w => w.Work).ToArray()];
             }
             else
             {

src/Microsoft.TestPlatform.CrossPlatEngine/Client/Parallel/ParallelProxyExecutionManager.cs

@@ -261,7 +261,7 @@ private List<ProviderSpecificWorkload<TestRunCriteria>> SplitToWorkloads(TestRun
                 if (!_isParallel && testhostProviderInfo.Shared)
                 {
                     // Create one big batch of testcases that will be single workload for single testhost.
-                    testCaseBatches = new List<TestCase[]> { group.SelectMany(w => sourceToTestCasesMap[w.Work]).ToArray() };
+                    testCaseBatches = [group.SelectMany(w => sourceToTestCasesMap[w.Work]).ToArray()];
                 }
                 else
                 {
@@ -319,7 +319,7 @@ private List<ProviderSpecificWorkload<TestRunCriteria>> SplitToWorkloads(TestRun
                 if (!_isParallel && testhostProviderInfo.Shared)
                 {
                     // Create one big source batch that will be single workload for single testhost.
-                    sourceBatches = new List<string[]> { group.Select(w => w.Work).ToArray() };
+                    sourceBatches = [group.Select(w => w.Work).ToArray()];
                 }
                 else
                 {

src/Microsoft.TestPlatform.CrossPlatEngine/Client/TestLoggerManager.cs

@@ -543,7 +543,7 @@ private bool InitializeLoggerByType(string assemblyQualifiedName, string codeBas
 
             // Create logger instance
             var constructorInfo = loggerType?.GetConstructor(Type.EmptyTypes);
-            var logger = constructorInfo?.Invoke(new object[] { });
+            var logger = constructorInfo?.Invoke([]);
 
             // Handle logger null scenario.
             if (logger == null)