Remove Nito.AsyncEx dependency, add replacements

src/PowerShellEditorServices.Host.x86/PowerShellEditorServices.Host.x86.csproj

@@ -37,18 +37,6 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="Newtonsoft.Json, Version=7.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed" />
-    <Reference Include="Nito.AsyncEx, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
-    <Reference Include="Nito.AsyncEx.Concurrent, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.Concurrent.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
-    <Reference Include="Nito.AsyncEx.Enlightenment, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.Enlightenment.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="System.Xml.Linq" />
@@ -71,7 +59,6 @@
     <None Include="..\PowerShellEditorServices.Host\App.config">
       <Link>App.config</Link>
     </None>
-    <None Include="packages.config" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\submodules\PSScriptAnalyzer\Engine\ScriptAnalyzerEngine.csproj">

src/PowerShellEditorServices.Host/PowerShellEditorServices.Host.csproj

@@ -39,18 +39,6 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="Newtonsoft.Json, Version=7.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed" />
-    <Reference Include="Nito.AsyncEx, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
-    <Reference Include="Nito.AsyncEx.Concurrent, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.Concurrent.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
-    <Reference Include="Nito.AsyncEx.Enlightenment, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.Enlightenment.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="System.Xml.Linq" />
@@ -69,7 +57,6 @@
     <Content Include="Microsoft.PowerShell.EditorServices.Host.DebugAdapter.cmd">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
-    <None Include="packages.config" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\submodules\PSScriptAnalyzer\Engine\ScriptAnalyzerEngine.csproj">

src/PowerShellEditorServices.Protocol/DebugAdapter/NextRequest.cs

@@ -4,8 +4,6 @@
 //
 
 using Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol;
-using Nito.AsyncEx;
-using System.Threading.Tasks;
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
 {

src/PowerShellEditorServices.Protocol/DebugAdapter/SetExceptionBreakpointsRequest.cs

@@ -4,8 +4,6 @@
 //
 
 using Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol;
-using Nito.AsyncEx;
-using System.Threading.Tasks;
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
 {

src/PowerShellEditorServices.Protocol/MessageProtocol/MessageDispatcher.cs

@@ -4,7 +4,6 @@
 //
 
 using Microsoft.PowerShell.EditorServices.Utility;
-using Nito.AsyncEx;
 using System;
 using System.Collections.Generic;
 using System.Threading;
@@ -26,6 +25,9 @@ public class MessageDispatcher
 
         private Action<Message> responseHandler;
 
+        private CancellationTokenSource messageLoopCancellationToken =
+            new CancellationTokenSource();
+
         #endregion
 
         #region Properties
@@ -65,22 +67,24 @@ public MessageDispatcher(
 
         public void Start()
         {
+
             // Start the main message loop thread.  The Task is
             // not explicitly awaited because it is running on
             // an independent background thread.
-            this.messageLoopThread = new AsyncContextThread(true);
+            this.messageLoopThread = new AsyncContextThread("Message Dispatcher");
             this.messageLoopThread
-                .Factory
-                .Run(this.ListenForMessages)
+                .Run(() => this.ListenForMessages(this.messageLoopCancellationToken.Token))
                 .ContinueWith(this.OnListenTaskCompleted);
         }
 
         public void Stop()
         {
-            // By disposing the thread we cancel all existing work
-            // and cause the thread to be destroyed.
+            // Stop the message loop thread
             if (this.messageLoopThread != null)
-                this.messageLoopThread.Dispose();
+            {
+                this.messageLoopCancellationToken.Cancel();
+                this.messageLoopThread.Stop();
+            }
         }
 
         public void SetRequestHandler<TParams, TResult>(
@@ -181,13 +185,13 @@ protected void OnUnhandledException(Exception unhandledException)
 
         #region Private Methods
 
-        private async Task ListenForMessages()
+        private async Task ListenForMessages(CancellationToken cancellationToken)
         {
             this.SynchronizationContext = SynchronizationContext.Current;
 
             // Run the message loop
             bool isRunning = true;
-            while (isRunning)
+            while (isRunning && !cancellationToken.IsCancellationRequested)
             {
                 Message newMessage = null;
 

src/PowerShellEditorServices.Protocol/MessageProtocol/MessageWriter.cs

@@ -6,7 +6,6 @@
 using Microsoft.PowerShell.EditorServices.Utility;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
-using Nito.AsyncEx;
 using System.IO;
 using System.Text;
 using System.Threading.Tasks;

src/PowerShellEditorServices.Protocol/PowerShellEditorServices.Protocol.csproj

@@ -38,18 +38,6 @@
       <HintPath>..\..\packages\Newtonsoft.Json.7.0.1\lib\net45\Newtonsoft.Json.dll</HintPath>
       <Private>True</Private>
     </Reference>
-    <Reference Include="Nito.AsyncEx, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
-    <Reference Include="Nito.AsyncEx.Concurrent, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.Concurrent.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
-    <Reference Include="Nito.AsyncEx.Enlightenment, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.Enlightenment.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="System.Xml.Linq" />

src/PowerShellEditorServices.Protocol/Server/LanguageServer.cs

@@ -8,7 +8,6 @@
 using Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol.Channel;
 using Microsoft.PowerShell.EditorServices.Protocol.Messages;
 using Microsoft.PowerShell.EditorServices.Utility;
-using Nito.AsyncEx;
 using System;
 using System.Collections.Generic;
 using System.IO;
@@ -780,7 +779,7 @@ private Task RunScriptDiagnostics(
             if (!this.currentSettings.ScriptAnalysis.Enable.Value)
             {
                 // If the user has disabled script analysis, skip it entirely
-                return TaskConstants.Completed;
+                return Task.FromResult(true);
             }
 
             // If there's an existing task, attempt to cancel it
@@ -806,7 +805,9 @@ private Task RunScriptDiagnostics(
                         "Exception while cancelling analysis task:\n\n{0}",
                         e.ToString()));
 
-                return TaskConstants.Canceled;
+                TaskCompletionSource<bool> cancelTask = new TaskCompletionSource<bool>();
+                cancelTask.SetCanceled();
+                return cancelTask.Task;
             }
 
             // Create a fresh cancellation token and then start the task.
@@ -826,7 +827,7 @@ private Task RunScriptDiagnostics(
                 TaskCreationOptions.None,
                 TaskScheduler.Default);
 
-            return TaskConstants.Completed;
+            return Task.FromResult(true);
         }
 
         private static async Task DelayThenInvokeDiagnostics(

src/PowerShellEditorServices.Protocol/packages.config

@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="Newtonsoft.Json" version="7.0.1" targetFramework="net45" />
-  <package id="Nito.AsyncEx" version="3.0.1" targetFramework="net45" />
 </packages>

src/PowerShellEditorServices/PowerShellEditorServices.csproj

@@ -38,18 +38,6 @@
     <DocumentationFile>bin\Release\Microsoft.PowerShell.EditorServices.XML</DocumentationFile>
   </PropertyGroup>
   <ItemGroup>
-    <Reference Include="Nito.AsyncEx, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
-    <Reference Include="Nito.AsyncEx.Concurrent, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.Concurrent.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
-    <Reference Include="Nito.AsyncEx.Enlightenment, Version=3.0.1.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\..\packages\Nito.AsyncEx.3.0.1\lib\net45\Nito.AsyncEx.Enlightenment.dll</HintPath>
-      <Private>True</Private>
-    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="System.Management.Automation" />
@@ -109,7 +97,12 @@
     <Compile Include="Session\SessionPSHostRawUserInterface.cs" />
     <Compile Include="Session\SessionPSHostUserInterface.cs" />
     <Compile Include="Session\SessionStateChangedEventArgs.cs" />
+    <Compile Include="Utility\AsyncContextThread.cs" />
+    <Compile Include="Utility\AsyncLock.cs" />
+    <Compile Include="Utility\AsyncQueue.cs" />
+    <Compile Include="Utility\AsyncContext.cs" />
     <Compile Include="Utility\Logger.cs" />
+    <Compile Include="Utility\ThreadSynchronizationContext.cs" />
     <Compile Include="Utility\Validate.cs" />
     <Compile Include="Workspace\BufferRange.cs" />
     <Compile Include="Workspace\FileChange.cs" />
@@ -119,9 +112,6 @@
     <Compile Include="Workspace\ScriptRegion.cs" />
     <Compile Include="Workspace\Workspace.cs" />
   </ItemGroup>
-  <ItemGroup>
-    <None Include="packages.config" />
-  </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\submodules\PSScriptAnalyzer\Engine\ScriptAnalyzerEngine.csproj">
       <Project>{f4bde3d0-3eef-4157-8a3e-722df7adef60}</Project>

src/PowerShellEditorServices/Session/PowerShellContext.cs

@@ -5,7 +5,6 @@
 
 using Microsoft.PowerShell.EditorServices.Console;
 using Microsoft.PowerShell.EditorServices.Utility;
-using Nito.AsyncEx;
 using System;
 using System.Collections;
 using System.Globalization;
@@ -44,8 +43,7 @@ public class PowerShellContext : IDisposable
         private TaskCompletionSource<IPipelineExecutionRequest> pipelineResultTask;
 
         private object runspaceMutex = new object();
-        private RunspaceHandle currentRunspaceHandle;
-        private IAsyncWaitQueue<RunspaceHandle> runspaceWaitQueue = new DefaultAsyncWaitQueue<RunspaceHandle>();
+        private AsyncQueue<RunspaceHandle> runspaceWaitQueue = new AsyncQueue<RunspaceHandle>();
 
         #endregion
 
@@ -115,6 +113,7 @@ public PowerShellContext()
             this.ownsInitialRunspace = true;
 
             this.Initialize(runspace);
+
         }
 
         /// <summary>
@@ -164,6 +163,10 @@ private void Initialize(Runspace initialRunspace)
 #endif
 
             this.SessionState = PowerShellContextState.Ready;
+
+            // Now that the runspace is ready, enqueue it for first use
+            RunspaceHandle runspaceHandle = new RunspaceHandle(this.currentRunspace, this);
+            this.runspaceWaitQueue.EnqueueAsync(runspaceHandle).Wait();
         }
 
         private Version GetPowerShellVersion()
@@ -198,21 +201,19 @@ private Version GetPowerShellVersion()
         /// <returns>A RunspaceHandle instance that gives access to the session's runspace.</returns>
         public Task<RunspaceHandle> GetRunspaceHandle()
         {
-            lock (this.runspaceMutex)
-            {
-                if (this.currentRunspaceHandle == null)
-                {
-                    this.currentRunspaceHandle = new RunspaceHandle(this.currentRunspace, this);
-                    TaskCompletionSource<RunspaceHandle> tcs = new TaskCompletionSource<RunspaceHandle>();
-                    tcs.SetResult(this.currentRunspaceHandle);
-                    return tcs.Task;
-                }
-                else
-                {
-                    // TODO: Use CancellationToken?
-                    return this.runspaceWaitQueue.Enqueue();
-                }
-            }
+            return this.GetRunspaceHandle(CancellationToken.None);
+        }
+
+        /// <summary>
+        /// Gets a RunspaceHandle for the session's runspace.  This
+        /// handle is used to gain temporary ownership of the runspace
+        /// so that commands can be executed against it directly.
+        /// </summary>
+        /// <param name="cancellationToken">A CancellationToken that can be used to cancel the request.</param>
+        /// <returns>A RunspaceHandle instance that gives access to the session's runspace.</returns>
+        public Task<RunspaceHandle> GetRunspaceHandle(CancellationToken cancellationToken)
+        {
+            return this.runspaceWaitQueue.DequeueAsync(cancellationToken);
         }
 
         /// <summary>
@@ -532,30 +533,17 @@ internal void ReleaseRunspaceHandle(RunspaceHandle runspaceHandle)
         {
             Validate.IsNotNull("runspaceHandle", runspaceHandle);
 
-            IDisposable dequeuedTask = null;
-
-            lock (this.runspaceMutex)
+            if (this.runspaceWaitQueue.IsEmpty)
             {
-                if (runspaceHandle != this.currentRunspaceHandle)
-                {
-                    throw new InvalidOperationException("Released runspace handle was not the current handle.");
-                }
-
-                this.currentRunspaceHandle = null;
-
-                if (!this.runspaceWaitQueue.IsEmpty)
-                {
-                    this.currentRunspaceHandle = new RunspaceHandle(this.currentRunspace, this);
-                    dequeuedTask =
-                        this.runspaceWaitQueue.Dequeue(
-                            this.currentRunspaceHandle);
-                }
+                var newRunspaceHandle = new RunspaceHandle(this.currentRunspace, this);
+                this.runspaceWaitQueue.EnqueueAsync(newRunspaceHandle).Wait();
             }
-
-            // If a queued task was dequeued, call Dispose to cause it to be executed.
-            if (dequeuedTask != null)
+            else
             {
-                dequeuedTask.Dispose();
+                // Write the situation to the log since this shouldn't happen
+                Logger.Write(
+                    LogLevel.Error,
+                    "The PowerShellContext.runspaceWaitQueue has more than one item");
             }
         }