Enable -sta and -mta switches for pwsh (#10061)

2026-06-08 12:12:50 +00:00 · 2019-07-25 12:38:52 -07:00
parent 87f537f290
commit 2ed9abc99b
24 changed files with 134 additions and 353 deletions
@@ -162,7 +162,7 @@ namespace Microsoft.PowerShell.Commands
            }

            thread.IsBackground = true;
-            // thread.SetApartmentState( ApartmentState.STA);
+            thread.SetApartmentState(ApartmentState.STA);
            thread.Start();
        }

@@ -395,7 +395,6 @@ namespace Microsoft.PowerShell.Commands
            return result;
        }

-#if !CORECLR
        private class ComCreateInfo
        {
            public object objectCreated;
@@ -435,7 +434,6 @@ namespace Microsoft.PowerShell.Commands
                info.success = false;
            }
        }
-#endif

        private object CreateComObject()
        {
@@ -459,13 +457,6 @@ namespace Microsoft.PowerShell.Commands
                // Check Error Code to see if Error is because of Com apartment Mismatch.
                if (e.HResult == RPC_E_CHANGED_MODE)
                {
-#if CORECLR
-                    ThrowTerminatingError(
-                        new ErrorRecord(
-                            new COMException(StringUtil.Format(NewObjectStrings.ApartmentNotSupported, e.Message), e),
-                            "NoCOMClassIdentified",
-                            ErrorCategory.ResourceUnavailable, null));
-#else
                    createInfo = new ComCreateInfo();

                    Thread thread = new Thread(new ParameterizedThreadStart(STAComCreateThreadProc));
@@ -482,7 +473,6 @@ namespace Microsoft.PowerShell.Commands
                    ThrowTerminatingError(
                             new ErrorRecord(createInfo.e, "NoCOMClassIdentified",
                                                    ErrorCategory.ResourceUnavailable, null));
-#endif
                }
                else
                {
@@ -173,10 +173,8 @@ namespace Microsoft.PowerShell
        private const int MaxPipePathLengthMacOS = 104;

        internal static string[] validParameters = {
-#if STAMODE
            "sta",
            "mta",
-#endif
            "command",
            "configurationname",
            "custompipename",
@@ -644,7 +642,6 @@ namespace Microsoft.PowerShell
            }
        }

-#if STAMODE
        internal bool StaMode
        {
            get
@@ -655,14 +652,10 @@ namespace Microsoft.PowerShell
                }
                else
                {
-                    // Nano doesn't support STA COM apartment, so on Nano powershell has to use MTA as the default.
-                    // return false;
-                    // Win8: 182409 PowerShell 3.0 should run in STA mode by default
                    return true;
                }
            }
        }
-#endif

        /// <summary>
        /// Processes all the command line parameters to ConsoleHost.  Returns the exit code to be used to terminate the process, or
@@ -944,10 +937,15 @@ namespace Microsoft.PowerShell
                        break;
                    }
                }
-#if STAMODE
-                // explicit setting of the ApartmentState Not supported on NanoServer
                else if (MatchSwitch(switchKey, "sta", "s"))
                {
+                    if (!Platform.IsWindowsDesktop)
+                    {
+                        WriteCommandLineError(
+                            CommandLineParameterParserStrings.STANotImplemented);
+                        break;
+                    }
+
                    if (_staMode.HasValue)
                    {
                        // -sta and -mta are mutually exclusive.
@@ -958,10 +956,15 @@ namespace Microsoft.PowerShell

                    _staMode = true;
                }
-                // Win8: 182409 PowerShell 3.0 should run in STA mode by default..so, consequently adding the switch -mta.
-                // Not deleting -sta for backward compatability reasons
                else if (MatchSwitch(switchKey, "mta", "mta"))
                {
+                    if (!Platform.IsWindowsDesktop)
+                    {
+                        WriteCommandLineError(
+                            CommandLineParameterParserStrings.MTANotImplemented);
+                        break;
+                    }
+
                    if (_staMode.HasValue)
                    {
                        // -sta and -mta are mutually exclusive.
@@ -972,7 +975,6 @@ namespace Microsoft.PowerShell

                    _staMode = false;
                }
-#endif
                else if (MatchSwitch(switchKey, "workingdirectory", "wo") || MatchSwitch(switchKey, "wd", "wd"))
                {
                    ++i;
@@ -1406,15 +1408,7 @@ namespace Microsoft.PowerShell
        private bool _abortStartup;
        private bool _skipUserInit;
        private string _customPipeName;
-#if STAMODE
-        // Win8: 182409 PowerShell 3.0 should run in STA mode by default
-        // -sta and -mta are mutually exclusive..so tracking them using nullable boolean
-        // if true, then sta is specified on the command line.
-        // if false, then mta is specified on the command line.
-        // if null, then none is specified on the command line..use default in this case
-        // default is sta.
        private bool? _staMode = null;
-#endif
        private bool _noExit = true;
        private bool _explicitReadCommandsFromStdin;
        private bool _noPrompt;
@@ -1373,11 +1373,7 @@ namespace Microsoft.PowerShell

                // NTRAID#Windows Out Of Band Releases-915506-2005/09/09
                // Removed HandleUnexpectedExceptions infrastructure
-#if STAMODE
                exitCode = DoRunspaceLoop(cpp.InitialCommand, cpp.SkipProfiles, cpp.Args, cpp.StaMode, cpp.ConfigurationName);
-#else
-                exitCode = DoRunspaceLoop(cpp.InitialCommand, cpp.SkipProfiles, cpp.Args, false, cpp.ConfigurationName);
-#endif
            }
            while (false);

@@ -1452,12 +1448,12 @@ namespace Microsoft.PowerShell

                _runspaceRef.Runspace.Close();
                _runspaceRef = null;
-#if STAMODE
-                if (staMode) // don't recycle the Runspace in STA mode
+
+                if (staMode)
                {
+                    // don't continue the session in STA mode
                    ShouldEndSession = true;
                }
-#endif
            }

            return ExitCode;
@@ -1496,11 +1492,7 @@ namespace Microsoft.PowerShell
            {
                args = runspaceCreationArgs as RunspaceCreationEventArgs;
                Dbg.Assert(args != null, "Event Arguments to CreateRunspace should not be null");
-#if STAMODE
                DoCreateRunspace(args.InitialCommand, args.SkipProfiles, args.StaMode, args.ConfigurationName, args.InitialCommandArgs);
-#else
-                DoCreateRunspace(args.InitialCommand, args.SkipProfiles, false, args.ConfigurationName, args.InitialCommandArgs);
-#endif
            }
            catch (ConsoleHostStartupException startupException)
            {
@@ -1618,17 +1610,11 @@ namespace Microsoft.PowerShell

        private void OpenConsoleRunspace(Runspace runspace, bool staMode)
        {
-#if STAMODE
-            // staMode will have following values:
-            // On FullPS: 'true'/'false' = default('true'=STA) + possibility of overload through cmdline parameter '-mta'
-            // On NanoPS: always 'false' = default('false'=MTA) + NO possibility of overload through cmdline parameter '-mta'
-            // ThreadOptions should match on FullPS and NanoPS for corresponding ApartmentStates.
-            if (staMode)
+            if (staMode && Platform.IsWindowsDesktop)
            {
-                // we can't change ApartmentStates on CoreCLR
                runspace.ApartmentState = ApartmentState.STA;
            }
-#endif
+
            runspace.ThreadOptions = PSThreadOptions.ReuseThread;
            runspace.EngineActivityId = EtwActivity.GetActivityId();

@@ -2896,18 +2882,14 @@ namespace Microsoft.PowerShell
        {
            InitialCommand = initialCommand;
            SkipProfiles = skipProfiles;
-#if STAMODE
            StaMode = staMode;
-#endif
            ConfigurationName = configurationName;
            InitialCommandArgs = initialCommandArgs;
        }

        internal string InitialCommand { get; set; }
        internal bool SkipProfiles { get; set; }
-#if STAMODE
        internal bool StaMode { get; set; }
-#endif
        internal string ConfigurationName { get; set; }
        internal Collection<CommandParameter> InitialCommandArgs { get; set; }
    }
@@ -210,4 +210,10 @@
  <data name="MissingWorkingDirectoryArgument" xml:space="preserve">
    <value>Cannot process the command because -WorkingDirectory requires an argument that is a directory path.</value>
  </data>
+  <data name="MTANotImplemented" xml:space="preserve">
+    <value>Parameter -MTA is not supported on this platform.</value>
+  </data>
+  <data name="STANotImplemented" xml:space="preserve">
+    <value>Parameter -STA is not supported on this platform.</value>
+  </data>
 </root>
@@ -131,8 +131,8 @@ Type 'help' to get help.</value>
                  [-ConfigurationName &lt;string&gt;] [-CustomPipeName &lt;string&gt;]
                  [-EncodedCommand &lt;Base64EncodedCommand&gt;]
                  [-ExecutionPolicy &lt;ExecutionPolicy&gt;] [-InputFormat {Text | XML}]
-                  [-Interactive] [-LoadProfile] [-NoExit] [-NoLogo] [-NonInteractive] [-NoProfile]
-                  [-OutputFormat {Text | XML}]  [-SettingsFile &lt;filePath&gt;] [-Version]
+                  [-Interactive] [-LoadProfile] [-MTA] [-NoExit] [-NoLogo] [-NonInteractive] [-NoProfile]
+                  [-OutputFormat {Text | XML}]  [-SettingsFile &lt;filePath&gt;] [-STA] [-Version]
                  [-WindowStyle &lt;style&gt;] [-WorkingDirectory &lt;directoryPath&gt;]

       pwsh[.exe] -h | -Help | -? | /?
@@ -298,6 +298,11 @@ All parameters are case-insensitive.</value>
    Load the PowerShell profiles. This is the default behavior even if this is
    not specified.

+-MTA
+
+    Start the shell using a multi-threaded apartment.
+    Only available on Windows.
+
 -NoExit | -noe

    Does not exit after running startup commands.
@@ -334,6 +339,11 @@ Hides the copyright banner at startup.

    Example: "pwsh -SettingsFile c:\myproject\powershell.config.json"

+-STA
+
+    Start the shell using a single-threaded apartment.  This is the default.
+    Only available on Windows.
+
 -Version | -v

    Displays the version of PowerShell. Additional parameters are ignored.
@@ -1671,9 +1671,7 @@ namespace System.Management.Automation.Runspaces
            ss.UseFullLanguageModeInDebugger = this.UseFullLanguageModeInDebugger;
            ss.ThreadOptions = this.ThreadOptions;
            ss.ThrowOnRunspaceOpenError = this.ThrowOnRunspaceOpenError;
-#if !CORECLR // No ApartmentState In CoreCLR
            ss.ApartmentState = this.ApartmentState;
-#endif

            foreach (ModuleSpecification modSpec in this.ModuleSpecificationsToImport)
            {
@@ -1812,14 +1810,11 @@ namespace System.Management.Automation.Runspaces
        /// </summary>
        public bool UseFullLanguageModeInDebugger { get; set; } = false;

-#if !CORECLR // No ApartmentState In CoreCLR
        /// <summary>
        /// ApartmentState of the thread used to execute commands.
        /// </summary>
        public ApartmentState ApartmentState { get; set; } = Runspace.DefaultApartmentState;

-#endif
-
        /// <summary>
        /// This property determines whether a new thread is created for each invocation of a command.
        /// </summary>
@@ -582,7 +582,6 @@ namespace System.Management.Automation.Runspaces
            }
        }

-#if !CORECLR // No ApartmentState In CoreCLR
        internal const ApartmentState DefaultApartmentState = ApartmentState.Unknown;

        /// <summary>
@@ -613,7 +612,6 @@ namespace System.Management.Automation.Runspaces
        }

        private ApartmentState apartmentState = Runspace.DefaultApartmentState;
-#endif

        /// <summary>
        /// This property determines whether a new thread is create for each invocation.
@@ -77,10 +77,7 @@ namespace System.Management.Automation.Runspaces
            Host = host;
            InitialSessionState = initialSessionState.Clone();
            this.ThreadOptions = initialSessionState.ThreadOptions;
-
-#if !CORECLR // No ApartmentState In CoreCLR
            this.ApartmentState = initialSessionState.ApartmentState;
-#endif
        }

        /// <summary>
@@ -126,10 +123,7 @@ namespace System.Management.Automation.Runspaces
            }

            this.ThreadOptions = initialSessionState.ThreadOptions;
-
-#if !CORECLR // No ApartmentState In CoreCLR
            this.ApartmentState = initialSessionState.ApartmentState;
-#endif
        }

        /// <summary>
@@ -920,7 +914,6 @@ namespace System.Management.Automation.Runspaces
                    waitHandles[i] = runningPipelines[i].PipelineFinishedEvent;
                }

-#if !CORECLR    // No ApartmentState.STA In CoreCLR
                // WaitAll for multiple handles on a STA (single-thread apartment) thread is not supported as WaitAll will prevent the message pump to run
                if (runningPipelines.Length > 1 && Thread.CurrentThread.GetApartmentState() == ApartmentState.STA)
                {
@@ -940,7 +933,7 @@ namespace System.Management.Automation.Runspaces
                        return waitAllIsDone.WaitOne();
                    }
                }
-#endif
+
                return WaitHandle.WaitAll(waitHandles);
            }
            else
@@ -146,32 +146,32 @@ namespace System.Management.Automation.Runspaces
            {
                lock (this.SyncRoot)
                {
-                    if (value != _createThreadOptions)
+                    if (value == _createThreadOptions)
                    {
-                        if (this.RunspaceStateInfo.State != RunspaceState.BeforeOpen)
-                        {
-#if CORECLR                 // No ApartmentState.STA Support In CoreCLR
-                            bool allowed = value == PSThreadOptions.ReuseThread;
-#else
-                            // if the runspace is already opened we only allow changing the options if
-                            // the apartment state is MTA and the new value is ReuseThread
-                            bool allowed = (this.ApartmentState == ApartmentState.MTA || this.ApartmentState == ApartmentState.Unknown) // Unknown is the same as MTA
-                                           &&
-                                           value == PSThreadOptions.ReuseThread;
-#endif
-
-                            if (!allowed)
-                            {
-                                throw new InvalidOperationException(StringUtil.Format(RunspaceStrings.InvalidThreadOptionsChange));
-                            }
-                        }
-
-                        _createThreadOptions = value;
+                        return;
                    }
+
+                    if (this.RunspaceStateInfo.State != RunspaceState.BeforeOpen)
+                    {
+                        if (!IsValidThreadOptionsConfiguration(value))
+                        {
+                            throw new InvalidOperationException(StringUtil.Format(RunspaceStrings.InvalidThreadOptionsChange));
+                        }
+                    }
+
+                    _createThreadOptions = value;
                }
            }
        }

+        private bool IsValidThreadOptionsConfiguration(PSThreadOptions options)
+        {
+            // If the runspace is already opened, we only allow changing options when:
+            //  - The new value is ReuseThread, and
+            //  - The apartment state is not STA
+            return options == PSThreadOptions.ReuseThread && this.ApartmentState != ApartmentState.STA;
+        }
+
        private PSThreadOptions _createThreadOptions = PSThreadOptions.Default;

        /// <summary>
@@ -770,11 +770,7 @@ namespace System.Management.Automation.Runspaces
        {
            if (_pipelineThread == null)
            {
-#if CORECLR     // No ApartmentState In CoreCLR
-                _pipelineThread = new PipelineThread();
-#else
                _pipelineThread = new PipelineThread(this.ApartmentState);
-#endif
            }

            return _pipelineThread;
@@ -179,8 +179,7 @@ namespace System.Management.Automation.Runspaces
                        // and support impersonation flow as needed (Windows only).
                        Thread invokeThread = new Thread(new ThreadStart(invokeThreadProcDelegate), DefaultPipelineStackSize);
                        SetupInvokeThread(invokeThread, true);
-#if !CORECLR
-                        // No ApartmentState in CoreCLR
+
                        ApartmentState apartmentState;

                        if (InvocationSettings != null && InvocationSettings.ApartmentState != ApartmentState.Unknown)
@@ -192,11 +191,13 @@ namespace System.Management.Automation.Runspaces
                            apartmentState = this.LocalRunspace.ApartmentState; // use the Runspace apartment state
                        }

-                        if (apartmentState != ApartmentState.Unknown)
+#if !UNIX
+                        if (apartmentState != ApartmentState.Unknown && !Platform.IsNanoServer && !Platform.IsIoT)
                        {
                            invokeThread.SetApartmentState(apartmentState);
                        }
 #endif
+
                        invokeThread.Start();

                        break;
@@ -1188,15 +1189,6 @@ namespace System.Management.Automation.Runspaces
        /// <summary>
        /// Creates the worker thread and waits for it to be ready.
        /// </summary>
-#if CORECLR
-        internal PipelineThread()
-        {
-            _worker = new Thread(WorkerProc, LocalPipeline.DefaultPipelineStackSize);
-            _workItem = null;
-            _workItemReady = new AutoResetEvent(false);
-            _closed = false;
-        }
-#else
        internal PipelineThread(ApartmentState apartmentState)
        {
            _worker = new Thread(WorkerProc, LocalPipeline.DefaultPipelineStackSize);
@@ -1204,12 +1196,13 @@ namespace System.Management.Automation.Runspaces
            _workItemReady = new AutoResetEvent(false);
            _closed = false;

-            if (apartmentState != ApartmentState.Unknown)
+#if !UNIX
+            if (apartmentState != ApartmentState.Unknown && !Platform.IsNanoServer && !Platform.IsIoT)
            {
                _worker.SetApartmentState(apartmentState);
            }
-        }
 #endif
+        }

        /// <summary>
        /// Returns the worker thread.
@@ -328,9 +328,7 @@ namespace System.Management.Automation
        /// </summary>
        public PSInvocationSettings()
        {
-#if !CORECLR // No ApartmentState In CoreCLR
            this.ApartmentState = ApartmentState.Unknown;
-#endif
            _host = null;
            RemoteStreamOptions = 0;
            AddToHistory = false;
@@ -339,13 +337,11 @@ namespace System.Management.Automation

        #endregion

-#if !CORECLR // No ApartmentState In CoreCLR
        /// <summary>
        /// ApartmentState of the thread in which the command
        /// is executed.
        /// </summary>
        public ApartmentState ApartmentState { get; set; }
-#endif

        /// <summary>
        /// Host to use with the Runspace when the command is
@@ -4530,9 +4526,8 @@ namespace System.Management.Automation
                {
                    if (pool != null)
                    {
-#if !CORECLR            // No ApartmentState In CoreCLR
                        VerifyThreadSettings(settings, pool.ApartmentState, pool.ThreadOptions, false);
-#endif
+
                        // getting the runspace asynchronously so that Stop can be supported from a different
                        // thread.
                        _worker.GetRunspaceAsyncResult = pool.BeginGetRunspace(null, null);
@@ -4544,9 +4539,8 @@ namespace System.Management.Automation
                        rsToUse = _rsConnection as Runspace;
                        if (rsToUse != null)
                        {
-#if !CORECLR                // No ApartmentState In CoreCLR
                            VerifyThreadSettings(settings, rsToUse.ApartmentState, rsToUse.ThreadOptions, false);
-#endif
+
                            if (rsToUse.RunspaceStateInfo.State != RunspaceState.Opened)
                            {
                                string message = StringUtil.Format(PowerShellStrings.InvalidRunspaceState, RunspaceState.Opened, rsToUse.RunspaceStateInfo.State);
@@ -4810,9 +4804,8 @@ namespace System.Management.Automation
                {
                    if (pool != null)
                    {
-#if !CORECLR            // No ApartmentState In CoreCLR
                        VerifyThreadSettings(settings, pool.ApartmentState, pool.ThreadOptions, pool.IsRemote);
-#endif
+
                        pool.AssertPoolIsOpen();

                        // for executing in a remote runspace pool case
@@ -4888,9 +4881,8 @@ namespace System.Management.Automation
                        LocalRunspace rs = _rsConnection as LocalRunspace;
                        if (rs != null)
                        {
-#if !CORECLR                // No ApartmentState In CoreCLR
                            VerifyThreadSettings(settings, rs.ApartmentState, rs.ThreadOptions, false);
-#endif
+
                            if (rs.RunspaceStateInfo.State != RunspaceState.Opened)
                            {
                                string message = StringUtil.Format(PowerShellStrings.InvalidRunspaceState, RunspaceState.Opened, rs.RunspaceStateInfo.State);
@@ -4939,7 +4931,6 @@ namespace System.Management.Automation
            return _invokeAsyncResult;
        }

-#if !CORECLR // No ApartmentState In CoreCLR
        /// <summary>
        /// Verifies the settings for ThreadOptions and ApartmentState.
        /// </summary>
@@ -4974,7 +4965,6 @@ namespace System.Management.Automation
                }
            }
        }
-#endif

        /// <summary>
        /// </summary>
@@ -1259,7 +1259,6 @@ namespace System.Management.Automation.Runspaces
            }
        }

-#if !CORECLR // No ApartmentState In CoreCLR
        /// <summary>
        /// ApartmentState of the thread used to execute commands within this RunspacePool.
        /// </summary>
@@ -1286,7 +1285,6 @@ namespace System.Management.Automation.Runspaces
                _internalPool.ApartmentState = value;
            }
        }
-#endif

        /// <summary>
        /// Gets Runspace asynchronously from the runspace pool. The caller
@@ -132,10 +132,7 @@ namespace System.Management.Automation.Runspaces.Internal
            _initialSessionState = initialSessionState.Clone();
            this.host = host;
            ThreadOptions = initialSessionState.ThreadOptions;
-#if !CORECLR
-            // No ApartmentState In CoreCLR
            this.ApartmentState = initialSessionState.ApartmentState;
-#endif
            pool = new Stack<Runspace>();
            runspaceRequestQueue = new Queue<GetRunspaceAsyncResult>();
            ultimateRequestQueue = new Queue<GetRunspaceAsyncResult>();
@@ -851,7 +848,6 @@ namespace System.Management.Automation.Runspaces.Internal
        /// </remarks>
        internal PSThreadOptions ThreadOptions { get; set; } = PSThreadOptions.Default;

-#if !CORECLR // No ApartmentState In CoreCLR
        /// <summary>
        /// The value of this property is propagated to all the Runspaces in this pool.
        /// </summary>
@@ -859,7 +855,6 @@ namespace System.Management.Automation.Runspaces.Internal
        /// Any updates to the value of this property must be done before the RunspacePool is opened
        /// </remarks>
        internal ApartmentState ApartmentState { get; set; } = Runspace.DefaultApartmentState;
-#endif

        /// <summary>
        /// Gets Runspace asynchronously from the runspace pool. The caller
@@ -1257,9 +1252,7 @@ namespace System.Management.Automation.Runspaces.Internal
            Runspace result = RunspaceFactory.CreateRunspaceFromSessionStateNoClone(host, _initialSessionState);

            result.ThreadOptions = this.ThreadOptions == PSThreadOptions.Default ? PSThreadOptions.ReuseThread : this.ThreadOptions;
-#if !CORECLR // No ApartmentState In CoreCLR
            result.ApartmentState = this.ApartmentState;
-#endif

            this.PropagateApplicationPrivateData(result);

@@ -554,9 +554,7 @@ namespace System.Management.Automation
            try
            {
                RunspacePool.ThreadOptions = this.ThreadOptions;
-#if !CORECLR // No ApartmentState In CoreCLR
                RunspacePool.ApartmentState = this.ApartmentState;
-#endif
                RunspacePool.Open();
            }
            catch (InvalidRunspacePoolStateException e)
@@ -8,6 +8,7 @@ using System.Globalization;
 using System.IO;
 using System.Security.AccessControl;
 using System.Text;
+using System.Threading;

 using System.Management.Automation;
 using System.Management.Automation.Internal;
@@ -1050,7 +1051,6 @@ else
                    maxObjectSizeMB.Value,
                    Environment.NewLine));
            }
-#if !CORECLR // No ApartmentState In CoreCLR
            if (threadAptState.HasValue)
            {
                initParameters.Append(string.Format(CultureInfo.InvariantCulture,
@@ -1059,7 +1059,6 @@ else
                    threadAptState.Value,
                    Environment.NewLine));
            }
-#endif
            if (threadOptions.HasValue)
            {
                initParameters.Append(string.Format(CultureInfo.InvariantCulture,
@@ -2041,7 +2040,6 @@ else
        internal PSCredential runAsCredential;
        internal bool isRunAsCredentialSpecified;

-#if !CORECLR // No ApartmentState In CoreCLR
        /// <summary>
        /// ApartmentState of the Runspace created for the shell.
        /// </summary>
@@ -2062,7 +2060,6 @@ else
        }

        internal ApartmentState? threadAptState;
-#endif

        /// <summary>
        /// ThreadOptions of the Runspace created for the shell.
@@ -3227,9 +3224,7 @@ Set-PSSessionConfiguration $args[0] $args[1] $args[2] $args[3] $args[4] $args[5]
            ConfigurationDataFromXML.MAXRCVDOBJSIZETOKEN,
            ConfigurationDataFromXML.MAXRCVDCMDSIZETOKEN,
            ConfigurationDataFromXML.THREADOPTIONSTOKEN,
-#if !CORECLR // No ApartmentState In CoreCLR
            ConfigurationDataFromXML.THREADAPTSTATETOKEN,
-#endif
            ConfigurationDataFromXML.PSVERSIONTOKEN,
            ConfigurationDataFromXML.MAXPSVERSIONTOKEN,
            ConfigurationDataFromXML.SESSIONCONFIGTOKEN,
@@ -3854,12 +3849,10 @@ Set-PSSessionConfiguration $args[0] $args[1] $args[2] $args[3] $args[4] $args[5]
                result.Properties.Add(new PSNoteProperty(ConfigurationDataFromXML.MAXRCVDOBJSIZETOKEN, input));
            }

-#if !CORECLR // No ApartmentState In CoreCLR
            if (threadAptState.HasValue)
            {
                result.Properties.Add(new PSNoteProperty(ConfigurationDataFromXML.THREADAPTSTATETOKEN, threadAptState.Value));
            }
-#endif

            if (threadOptions.HasValue)
            {
@@ -3459,16 +3459,6 @@ namespace System.Management.Automation.Runspaces
        /// </summary>
        private void RunOnMTAThread(ThreadStart threadProc)
        {
-            //
-            // By default, non-OneCore PowerShell is launched with ApartmentState being STA.
-            // In this case, we need to create a separate thread, set its ApartmentState to MTA,
-            // and do the work.
-            //
-            // For OneCore PowerShell, its ApartmentState is always MTA.
-            //
-#if CORECLR
-            threadProc();
-#else
            if (Thread.CurrentThread.GetApartmentState() == ApartmentState.MTA)
            {
                threadProc();
@@ -3481,7 +3471,6 @@ namespace System.Management.Automation.Runspaces
                executionThread.Start();
                executionThread.Join();
            }
-#endif
        }

        /// <summary>
@@ -677,11 +677,7 @@ namespace System.Management.Automation
            dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.MinRunspaces, minRunspaces));
            dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.MaxRunspaces, maxRunspaces));
            dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.ThreadOptions, runspacePool.ThreadOptions));
-#if CORECLR // No ApartmentState In CoreCLR, default to MTA for outgoing objects
-            ApartmentState poolState = ApartmentState.MTA;
-#else
            ApartmentState poolState = runspacePool.ApartmentState;
-#endif
            dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.ApartmentState, poolState));
            dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.ApplicationArguments, applicationArguments));

@@ -1113,11 +1109,7 @@ namespace System.Management.Automation
                hostInfo = new HostInfo(null);
                hostInfo.UseRunspaceHost = true;

-#if CORECLR // No ApartmentState In CoreCLR, default to MTA for outgoing objects
-                ApartmentState passedApartmentState = ApartmentState.MTA;
-#else
                ApartmentState passedApartmentState = rsPool.ApartmentState;
-#endif
                dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.ApartmentState, passedApartmentState));
                dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.RemoteStreamOptions, RemoteStreamOptions.AddInvocationInfo));
                dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.AddToHistory, false));
@@ -1130,11 +1122,7 @@ namespace System.Management.Automation
                    hostInfo.UseRunspaceHost = true;
                }

-#if CORECLR // No ApartmentState In CoreCLR, default to MTA for outgoing objects
-                ApartmentState passedApartmentState = ApartmentState.MTA;
-#else
                ApartmentState passedApartmentState = settings.ApartmentState;
-#endif
                dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.ApartmentState, passedApartmentState));
                dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.RemoteStreamOptions, settings.RemoteStreamOptions));
                dataAsPSObject.Properties.Add(new PSNoteProperty(RemoteDataNameStrings.AddToHistory, settings.AddToHistory));
@@ -2341,7 +2329,6 @@ namespace System.Management.Automation
            return GetPropertyValue<bool>(dataAsPSObject, RemoteDataNameStrings.IsNested);
        }

-#if !CORECLR // No ApartmentState In CoreCLR
        /// <summary>
        /// Gets the invocation settings information from the message.
        /// </summary>
@@ -2352,7 +2339,7 @@ namespace System.Management.Automation
            PSObject dataAsPSObject = PSObject.AsPSObject(data);
            return GetPropertyValue<ApartmentState>(dataAsPSObject, RemoteDataNameStrings.ApartmentState);
        }
-#endif
+
        /// <summary>
        /// Gets the stream options from the message.
        /// </summary>
@@ -12,6 +12,7 @@ using System.Management.Automation.Internal;
 using System.Management.Automation.Runspaces;
 using System.Management.Automation.Tracing;
 using System.Reflection;
+using System.Threading;
 using System.Xml;

 using Microsoft.PowerShell.Commands;
@@ -44,9 +45,7 @@ namespace System.Management.Automation.Remoting
        internal const string MAXRCVDCMDSIZETOKEN = "psmaximumreceiveddatasizepercommandmb";
        internal const string MAXRCVDCMDSIZETOKEN_CamelCase = "PSMaximumReceivedDataSizePerCommandMB";
        internal const string THREADOPTIONSTOKEN = "pssessionthreadoptions";
-#if !CORECLR // No ApartmentState In CoreCLR
        internal const string THREADAPTSTATETOKEN = "pssessionthreadapartmentstate";
-#endif
        internal const string SESSIONCONFIGTOKEN = "sessionconfigurationdata";
        internal const string PSVERSIONTOKEN = "PSVersion";
        internal const string MAXPSVERSIONTOKEN = "MaxPSVersion";
@@ -68,10 +67,7 @@ namespace System.Management.Automation.Remoting
        internal int? MaxReceivedCommandSizeMB;
        // Used to set properties on the RunspacePool created for this shell.
        internal PSThreadOptions? ShellThreadOptions;
-
-#if !CORECLR // No ApartmentState In CoreCLR
-        internal Nullable<System.Threading.ApartmentState> ShellThreadApartmentState;
-#endif
+        internal ApartmentState? ShellThreadApartmentState;
        internal PSSessionConfigurationData SessionConfigurationData;
        internal string ConfigFilePath;

@@ -127,13 +123,11 @@ namespace System.Management.Automation.Remoting
                    ShellThreadOptions = (PSThreadOptions)LanguagePrimitives.ConvertTo(
                        optionValue, typeof(PSThreadOptions), CultureInfo.InvariantCulture);
                    break;
-#if !CORECLR // No ApartmentState In CoreCLR
                case THREADAPTSTATETOKEN:
                    AssertValueNotAssigned(THREADAPTSTATETOKEN, ShellThreadApartmentState);
-                    ShellThreadApartmentState = (System.Threading.ApartmentState)LanguagePrimitives.ConvertTo(
-                        optionValue, typeof(System.Threading.ApartmentState), CultureInfo.InvariantCulture);
+                    ShellThreadApartmentState = (ApartmentState)LanguagePrimitives.ConvertTo(
+                        optionValue, typeof(ApartmentState), CultureInfo.InvariantCulture);
                    break;
-#endif
                case SESSIONCONFIGTOKEN:
                    {
                        AssertValueNotAssigned(SESSIONCONFIGTOKEN, SessionConfigurationData);
@@ -42,11 +42,8 @@ namespace System.Management.Automation
        // associated with this powershell
        private ServerRemoteHost _remoteHost;

-#if !CORECLR
-        // No ApartmentState In CoreCLR
        // apartment state for this powershell
        private ApartmentState apartmentState;
-#endif

        // Handles nested invocation of PS drivers.
        private IRSPDriverInvoke _psDriverInvoker;
@@ -55,7 +52,6 @@ namespace System.Management.Automation

        #region Constructors

-#if !CORECLR
        /// <summary>
        /// Default constructor for creating ServerPowerShellDrivers.
        /// </summary>
@@ -85,66 +81,7 @@ namespace System.Management.Automation
                   apartmentState, hostInfo, streamOptions, addToHistory, rsToUse, null)
        {
        }
-#else
-        /// <summary>
-        /// Default constructor for creating ServerPowerShellDrivers.
-        /// </summary>
-        /// <param name="powershell">Decoded powershell object.</param>
-        /// <param name="extraPowerShell">Extra pipeline to be run after <paramref name="powershell"/> completes.</param>
-        /// <param name="noInput">Whether there is input for this powershell.</param>
-        /// <param name="clientPowerShellId">The client powershell id.</param>
-        /// <param name="clientRunspacePoolId">The client runspacepool id.</param>
-        /// <param name="runspacePoolDriver">runspace pool driver
-        /// which is creating this powershell driver</param>
-        /// <param name="hostInfo">host info using which the host for
-        /// this powershell will be constructed</param>
-        /// <param name="streamOptions">Serialization options for the streams in this powershell.</param>
-        /// <param name="addToHistory">
-        /// true if the command is to be added to history list of the runspace. false, otherwise.
-        /// </param>
-        /// <param name="rsToUse">
-        /// If not null, this Runspace will be used to invoke Powershell.
-        /// If null, the RunspacePool pointed by <paramref name="runspacePoolDriver"/> will be used.
-        /// </param>
-        internal ServerPowerShellDriver(PowerShell powershell, PowerShell extraPowerShell, bool noInput, Guid clientPowerShellId,
-           Guid clientRunspacePoolId, ServerRunspacePoolDriver runspacePoolDriver,
-           HostInfo hostInfo, RemoteStreamOptions streamOptions,
-           bool addToHistory, Runspace rsToUse)
-            : this(powershell, extraPowerShell, noInput, clientPowerShellId, clientRunspacePoolId, runspacePoolDriver,
-                   hostInfo, streamOptions, addToHistory, rsToUse, null)
-        {
-        }
-#endif

-#if CORECLR
-        /// <summary>
-        /// Default constructor for creating ServerPowerShellDrivers.
-        /// </summary>
-        /// <param name="powershell">Decoded powershell object.</param>
-        /// <param name="extraPowerShell">Extra pipeline to be run after <paramref name="powershell"/> completes.</param>
-        /// <param name="noInput">Whether there is input for this powershell.</param>
-        /// <param name="clientPowerShellId">The client powershell id.</param>
-        /// <param name="clientRunspacePoolId">The client runspacepool id.</param>
-        /// <param name="runspacePoolDriver">runspace pool driver
-        /// which is creating this powershell driver</param>
-        /// <param name="hostInfo">host info using which the host for
-        /// this powershell will be constructed</param>
-        /// <param name="streamOptions">Serialization options for the streams in this powershell.</param>
-        /// <param name="addToHistory">
-        /// true if the command is to be added to history list of the runspace. false, otherwise.
-        /// </param>
-        /// <param name="rsToUse">
-        /// If not null, this Runspace will be used to invoke Powershell.
-        /// If null, the RunspacePool pointed by <paramref name="runspacePoolDriver"/> will be used.
-        /// </param>
-        /// <param name="output">
-        /// If not null, this is used as another source of output sent to the client.
-        /// </param>
-        internal ServerPowerShellDriver(PowerShell powershell, PowerShell extraPowerShell, bool noInput, Guid clientPowerShellId,
-            Guid clientRunspacePoolId, ServerRunspacePoolDriver runspacePoolDriver,
-            HostInfo hostInfo, RemoteStreamOptions streamOptions,
-            bool addToHistory, Runspace rsToUse, PSDataCollection<PSObject> output)
-#else
        /// <summary>
        /// Default constructor for creating ServerPowerShellDrivers.
        /// </summary>
@@ -173,14 +110,11 @@ namespace System.Management.Automation
            Guid clientRunspacePoolId, ServerRunspacePoolDriver runspacePoolDriver,
            ApartmentState apartmentState, HostInfo hostInfo, RemoteStreamOptions streamOptions,
            bool addToHistory, Runspace rsToUse, PSDataCollection<PSObject> output)
-#endif
        {
            InstanceId = clientPowerShellId;
            RunspacePoolId = clientRunspacePoolId;
            RemoteStreamOptions = streamOptions;
-#if !CORECLR // No ApartmentState In CoreCLR
            this.apartmentState = apartmentState;
-#endif
            LocalPowerShell = powershell;
            _extraPowerShell = extraPowerShell;
            _localPowerShellOutput = new PSDataCollection<PSObject>();
@@ -298,9 +232,7 @@ namespace System.Management.Automation
            }

            PSInvocationSettings settings = new PSInvocationSettings();
-#if !CORECLR // No ApartmentState In CoreCLR
            settings.ApartmentState = apartmentState;
-#endif
            settings.Host = _remoteHost;

            // Flow the impersonation policy to pipeline execution thread
@@ -95,46 +95,6 @@ namespace System.Management.Automation

        #region Constructors

-#if CORECLR // No ApartmentState In CoreCLR
-        /// <summary>
-        /// Creates the runspace pool driver.
-        /// </summary>
-        /// <param name="clientRunspacePoolId">Client runspace pool id to associate.</param>
-        /// <param name="transportManager">transport manager associated with this
-        /// runspace pool driver</param>
-        /// <param name="maxRunspaces">Maximum runspaces to open.</param>
-        /// <param name="minRunspaces">Minimum runspaces to open.</param>
-        /// <param name="threadOptions">Threading options for the runspaces in the pool.</param>
-        /// <param name="hostInfo">Host information about client side host.</param>
-        /// <param name="configData">
-        /// Contains:
-        /// 1. Script to run after a RunspacePool/Runspace is created in this session.
-        /// For RunspacePool case, every newly created Runspace (in the pool) will run
-        /// this script.
-        /// 2. ThreadOptions for RunspacePool/Runspace
-        /// 3. ThreadApartment for RunspacePool/Runspace
-        /// </param>
-        /// <param name="initialSessionState">Configuration of the runspace.</param>
-        /// <param name="applicationPrivateData">Application private data.</param>
-        /// <param name="isAdministrator">True if the driver is being created by an administrator.</param>
-        /// <param name="serverCapability">Server capability reported to the client during negotiation (not the actual capability).</param>
-        /// <param name="psClientVersion">Client PowerShell version.</param>
-        /// <param name="configurationName">Optional endpoint configuration name to create a pushed configured runspace.</param>
-        internal ServerRunspacePoolDriver(
-            Guid clientRunspacePoolId,
-            int minRunspaces,
-            int maxRunspaces,
-            PSThreadOptions threadOptions,
-            HostInfo hostInfo,
-            InitialSessionState initialSessionState,
-            PSPrimitiveDictionary applicationPrivateData,
-            ConfigurationDataFromXML configData,
-            AbstractServerSessionTransportManager transportManager,
-            bool isAdministrator,
-            RemoteSessionCapability serverCapability,
-            Version psClientVersion,
-            string configurationName)
-#else
        /// <summary>
        /// Creates the runspace pool driver.
        /// </summary>
@@ -175,7 +135,6 @@ namespace System.Management.Automation
            RemoteSessionCapability serverCapability,
            Version psClientVersion,
            string configurationName)
-#endif
        {
            Dbg.Assert(configData != null, "ConfigurationData cannot be null");

@@ -213,7 +172,6 @@ namespace System.Management.Automation
                RunspacePool.ThreadOptions = threadOptions;
            }

-#if !CORECLR // No ApartmentState In CoreCLR
            // Set Thread ApartmentState for this RunspacePool
            ApartmentState serverApartmentState = configData.ShellThreadApartmentState.HasValue ? configData.ShellThreadApartmentState.Value : Runspace.DefaultApartmentState;

@@ -225,7 +183,6 @@ namespace System.Management.Automation
            {
                RunspacePool.ApartmentState = apartmentState;
            }
-#endif

            // If we have a runspace pool with a single runspace then we can run nested pipelines on
            // on it in a single pipeline invoke thread.
@@ -579,9 +536,7 @@ namespace System.Management.Automation
                Guid.Empty,
                this.InstanceId,
                this,
-#if !CORECLR // No ApartmentState In CoreCLR
                args.Runspace.ApartmentState,
-#endif
                hostInfo,
                RemoteStreamOptions.AddInvocationInfo,
                false,
@@ -760,9 +715,7 @@ namespace System.Management.Automation
            // invoked from within the driver
            HostInfo hostInfo = RemotingDecoder.GetHostInfo(data.Data);

-#if !CORECLR // No ApartmentState In CoreCLR
            ApartmentState apartmentState = RemotingDecoder.GetApartmentState(data.Data);
-#endif

            RemoteStreamOptions streamOptions = RemotingDecoder.GetRemoteStreamOptions(data.Data);
            PowerShell powershell = RemotingDecoder.GetPowerShell(data.Data);
@@ -824,9 +777,7 @@ namespace System.Management.Automation
                        data.PowerShellId,
                        data.RunspacePoolId,
                        this,
-#if !CORECLR // No ApartmentState In CoreCLR
                        apartmentState,
-#endif
                        hostInfo,
                        streamOptions,
                        addToHistory,
@@ -883,9 +834,7 @@ namespace System.Management.Automation
                            data.PowerShellId,
                            data.RunspacePoolId,
                            this,
-#if !CORECLR // No ApartmentState In CoreCLR
                            apartmentState,
-#endif
                            hostInfo,
                            streamOptions,
                            addToHistory,
@@ -904,9 +853,7 @@ namespace System.Management.Automation
                            data.PowerShellId,
                            data.RunspacePoolId,
                            this,
-#if !CORECLR // No ApartmentState In CoreCLR
                            apartmentState,
-#endif
                            _remoteHost,
                            hostInfo,
                            streamOptions,
@@ -937,9 +884,7 @@ namespace System.Management.Automation
                            data.PowerShellId,
                            data.RunspacePoolId,
                            this,
-#if !CORECLR // No ApartmentState In CoreCLR
                            apartmentState,
-#endif
                            hostInfo,
                            streamOptions,
                            addToHistory,
@@ -971,9 +916,7 @@ namespace System.Management.Automation
                data.PowerShellId,
                data.RunspacePoolId,
                this,
-#if !CORECLR // No ApartmentState In CoreCLR
                apartmentState,
-#endif
                hostInfo,
                streamOptions,
                addToHistory,
@@ -1085,9 +1028,7 @@ namespace System.Management.Automation
                    data.PowerShellId,
                    data.RunspacePoolId,
                    this,
-#if !CORECLR // No ApartmentState In CoreCLR
                    ApartmentState.Unknown,
-#endif
                    useRunspaceHost,
                    0 /* stream options */,
                    false /* addToHistory */,
@@ -1224,9 +1165,7 @@ namespace System.Management.Automation
                powershellId,
                runspacePoolId,
                this,
-#if !CORECLR // No ApartmentState In CoreCLR
                ApartmentState.MTA,
-#endif
                hostInfo,
                streamOptions,
                addToHistory,
@@ -2519,9 +2458,7 @@ namespace System.Management.Automation
            Guid powershellId,
            Guid runspacePoolId,
            ServerRunspacePoolDriver runspacePoolDriver,
-#if !CORECLR // No ApartmentState In CoreCLR
            ApartmentState apartmentState,
-#endif
            ServerRemoteHost remoteHost,
            HostInfo hostInfo,
            RemoteStreamOptions streamOptions,
@@ -2557,9 +2494,7 @@ namespace System.Management.Automation
                    powershellId,
                    runspacePoolId,
                    runspacePoolDriver,
-#if !CORECLR // No ApartmentState In CoreCLR
                    apartmentState,
-#endif
                    hostInfo,
                    streamOptions,
                    addToHistory,
@@ -74,9 +74,7 @@ namespace System.Management.Automation
        // was created
        private bool _addToHistory;
        // associated with this powershell
-#if !CORECLR // No ApartmentState In CoreCLR
        private ApartmentState apartmentState;  // apartment state for this powershell
-#endif

        // pipeline that runs the actual command.
        private ServerSteppablePipelineSubscriber _eventSubscriber;
@@ -84,36 +82,6 @@ namespace System.Management.Automation

        #endregion

-#if CORECLR // No ApartmentState In CoreCLR
-        /// <summary>
-        /// Default constructor for creating ServerSteppablePipelineDriver...Used by server to concurrently
-        /// run 2 pipelines.
-        /// </summary>
-        /// <param name="powershell">Decoded powershell object.</param>
-        /// <param name="noInput">Whether there is input for this powershell.</param>
-        /// <param name="clientPowerShellId">The client powershell id.</param>
-        /// <param name="clientRunspacePoolId">The client runspacepool id.</param>
-        /// <param name="runspacePoolDriver">runspace pool driver
-        /// which is creating this powershell driver</param>
-        /// <param name="hostInfo">host info using which the host for
-        /// this powershell will be constructed</param>
-        /// <param name="streamOptions">Serialization options for the streams in this powershell.</param>
-        /// <param name="addToHistory">
-        /// true if the command is to be added to history list of the runspace. false, otherwise.
-        /// </param>
-        /// <param name="rsToUse">
-        /// If not null, this Runspace will be used to invoke Powershell.
-        /// If null, the RunspacePool pointed by <paramref name="runspacePoolDriver"/> will be used.
-        /// </param>
-        /// <param name="eventSubscriber">
-        /// Steppable pipeline event subscriber
-        /// </param>
-        /// <param name="powershellInput">Input collection of the PowerShell pipeline.</param>
-        internal ServerSteppablePipelineDriver(PowerShell powershell, bool noInput, Guid clientPowerShellId,
-            Guid clientRunspacePoolId, ServerRunspacePoolDriver runspacePoolDriver,
-            HostInfo hostInfo, RemoteStreamOptions streamOptions,
-            bool addToHistory, Runspace rsToUse, ServerSteppablePipelineSubscriber eventSubscriber, PSDataCollection<object> powershellInput)
-#else
        /// <summary>
        /// Default constructor for creating ServerSteppablePipelineDriver...Used by server to concurrently
        /// run 2 pipelines.
@@ -143,15 +111,12 @@ namespace System.Management.Automation
            Guid clientRunspacePoolId, ServerRunspacePoolDriver runspacePoolDriver,
            ApartmentState apartmentState, HostInfo hostInfo, RemoteStreamOptions streamOptions,
            bool addToHistory, Runspace rsToUse, ServerSteppablePipelineSubscriber eventSubscriber, PSDataCollection<object> powershellInput)
-#endif
        {
            LocalPowerShell = powershell;
            InstanceId = clientPowerShellId;
            RunspacePoolId = clientRunspacePoolId;
            RemoteStreamOptions = streamOptions;
-#if !CORECLR // No ApartmentState In CoreCLR
            this.apartmentState = apartmentState;
-#endif
            NoInput = noInput;
            _addToHistory = addToHistory;
            _eventSubscriber = eventSubscriber;
@@ -856,9 +856,7 @@ namespace System.Management.Automation.Remoting
            int minRunspaces = RemotingDecoder.GetMinRunspaces(rcvdData.Data);
            int maxRunspaces = RemotingDecoder.GetMaxRunspaces(rcvdData.Data);
            PSThreadOptions threadOptions = RemotingDecoder.GetThreadOptions(rcvdData.Data);
-#if !CORECLR // No ApartmentState In CoreCLR
            ApartmentState apartmentState = RemotingDecoder.GetApartmentState(rcvdData.Data);
-#endif
            HostInfo hostInfo = RemotingDecoder.GetHostInfo(rcvdData.Data);

            if (_runspacePoolDriver != null)
@@ -878,9 +876,7 @@ namespace System.Management.Automation.Remoting
                minRunspaces,
                maxRunspaces,
                threadOptions,
-#if !CORECLR // No ApartmentState In CoreCLR
                apartmentState,
-#endif
                hostInfo,
                rsSessionStateToUse,
                applicationPrivateData,
@@ -240,7 +240,7 @@ Describe "ConsoleHost unit tests" -tags "Feature" {
 '@
            $testFilePath = Join-Path $TestDrive "test.ps1"
            Set-Content -Path $testFilePath -Value $testScript
-            $observed = echo hello | pwsh $testFilePath e -
+            $observed = echo hello | pwsh -noprofile $testFilePath e -
            $observed | Should -BeExactly "h-llo"
        }
    }
@@ -711,8 +711,62 @@ namespace StackTest {
            $longPipeName = [string]::new("A", 200)

            "`$pid" | & $powershell -CustomPipeName $longPipeName -c -
-            # 64 is the ExitCode for BadCommandLineParameter
-            $LASTEXITCODE | Should -Be 64
+            $LASTEXITCODE | Should -Be $ExitCodeBadCommandLineParameter
+        }
+    }
+
+    Context "ApartmentState WPF tests" -Tag Slow {
+
+        It "WPF requires STA and will work" -Skip:(!$IsWindows -or [System.Management.Automation.Platform]::IsNanoServer) {
+            add-type -AssemblyName presentationframework
+
+            $xaml = [xml]@"
+            <Window
+                xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+                xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                x:Name="Window" Title="Initial Window" WindowStartupLocation = "CenterScreen"
+                Width = "400" Height = "300" ShowInTaskbar = "True">
+            </Window>
+"@
+
+            $reader = [System.Xml.XmlNodeReader]::new($xaml)
+            $Window = [System.Windows.Markup.XamlReader]::Load($reader)
+            # This will throw an exception if MTA
+            { $Window.Show() } | Should -Not -Throw
+            $Window.Close()
+        }
+
+    }
+
+    Context "ApartmentState tests" {
+
+        It "Default apartment state for main thread is STA" -Skip:(!$IsWindows -or [System.Management.Automation.Platform]::IsNanoServer) {
+            [System.Threading.Thread]::CurrentThread.GetApartmentState() | Should -BeExactly "STA"
+        }
+
+        It "Default apartment state for new runspace is MTA" -Skip:(!$IsWindows) {
+            $ps = [powershell]::Create()
+            $ps.AddScript({[System.Threading.Thread]::CurrentThread.GetApartmentState()})
+            $ps.Invoke() | Should -BeExactly "MTA"
+        }
+
+        It "Should be able to set apartment state to: <apartment>" -Skip:(!$IsWindows -or [System.Management.Automation.Platform]::IsNanoServer) -TestCases @(
+            @{ apartment = "STA"; switch = "-sta" }
+            @{ apartment = "MTA"; switch = "-mta" }
+        ) {
+            param ($apartment, $switch)
+
+            & $powershell $switch -noprofile -command "[System.Threading.Thread]::CurrentThread.GetApartmentState()" | Should -BeExactly $apartment
+        }
+
+        It "Should fail to set apartment state to: <switch>" -Skip:($IsWindows -and ![System.Management.Automation.Platform]::IsNanoServer) -TestCases @(
+            @{ switch = "-sta" }
+            @{ switch = "-mta" }
+        ) {
+            param ($switch)
+
+            & $powershell $switch -noprofile -command exit
+            $LASTEXITCODE | Should -Be $ExitCodeBadCommandLineParameter
        }
    }
 }
@@ -855,7 +909,7 @@ Describe 'Pwsh startup in directories that contain wild cards' -Tag CI {
        param ( $dirname )
        try {
            Push-Location -LiteralPath "${TESTDRIVE}/${dirname}"
-            $result = & $powershell -c '(Get-Item .).Name'
+            $result = & $powershell -noprofile -c '(Get-Item .).Name'
            $result | Should -BeExactly $dirname
        }
        finally {