Interrupt integrated console command prompt when commands are executed

src/PowerShellEditorServices.Protocol/Server/DebugAdapter.cs

@@ -100,9 +100,6 @@ protected override void Initialize()
 
         protected Task LaunchScript(RequestContext<object> requestContext)
         {
-            // Ensure the read loop is stopped
-            this.editorSession.ConsoleService.CancelReadLoop();
-
             // Is this an untitled script?
             Task launchTask = null;
 
@@ -144,9 +141,6 @@ private async Task OnExecutionCompleted(Task executeTask)
 
             if (this.isAttachSession)
             {
-                // Ensure the read loop is stopped
-                this.editorSession.ConsoleService.CancelReadLoop();
-
                 // Pop the sessions
                 if (this.editorSession.PowerShellContext.CurrentRunspace.Context == RunspaceContext.EnteredProcess)
                 {
@@ -165,12 +159,6 @@ private async Task OnExecutionCompleted(Task executeTask)
                         Logger.WriteException("Caught exception while popping attached process after debugging", e);
                     }
                 }
-
-            }
-
-            if (!this.ownsEditorSession)
-            {
-                this.editorSession.ConsoleService.StartReadLoop();
             }
 
             if (this.disconnectRequestContext != null)

src/PowerShellEditorServices.Protocol/Server/LanguageServer.cs

@@ -1108,9 +1108,6 @@ protected Task HandleEvaluateRequest(
             DebugAdapterMessages.EvaluateRequestArguments evaluateParams,
             RequestContext<DebugAdapterMessages.EvaluateResponseBody> requestContext)
         {
-            // Cancel the read loop before executing
-            this.editorSession.ConsoleService.CancelReadLoop();
-
             // We don't await the result of the execution here because we want
             // to be able to receive further messages while the current script
             // is executing.  This important in cases where the pipeline thread

src/PowerShellEditorServices/Console/ChoicePromptHandler.cs

@@ -199,8 +199,15 @@ private async Task<int[]> StartPromptLoop(
                     break;
                 }
 
-                // If the handler returns null it means we should prompt again
                 choiceIndexes = this.HandleResponse(responseString);
+
+                // Return the default choice values if no choices were entered
+                if (choiceIndexes == null && string.IsNullOrEmpty(responseString))
+                {
+                    choiceIndexes = this.DefaultChoices;
+                }
+
+                // If the user provided no choices, we should prompt again
                 if (choiceIndexes != null)
                 {
                     break;

src/PowerShellEditorServices/Console/ConsoleService.cs

@@ -79,6 +79,7 @@ public ConsoleService(
             this.powerShellContext.ConsoleHost = this;
             this.powerShellContext.DebuggerStop += PowerShellContext_DebuggerStop;
             this.powerShellContext.DebuggerResumed += PowerShellContext_DebuggerResumed;
+            this.powerShellContext.ExecutionStatusChanged += PowerShellContext_ExecutionStatusChanged;
 
             // Set the default prompt handler factory or create
             // a default if one is not provided
@@ -140,31 +141,6 @@ public void CancelReadLoop()
             }
         }
 
-        /// <summary>
-        /// Called when a command string is received from the user.
-        /// If a prompt is currently active, the prompt handler is
-        /// asked to handle the string.  Otherwise the string is
-        /// executed in the PowerShellContext.
-        /// </summary>
-        /// <param name="inputString">The input string to evaluate.</param>
-        /// <param name="echoToConsole">If true, the input will be echoed to the console.</param>
-        public void ExecuteCommand(string inputString, bool echoToConsole)
-        {
-            this.CancelReadLoop();
-
-            if (this.activePromptHandler == null)
-            {
-                // Execute the script string but don't wait for completion
-                var executeTask =
-                    this.powerShellContext
-                        .ExecuteScriptString(
-                            inputString,
-                            echoToConsole,
-                            true)
-                        .ConfigureAwait(false);
-            }
-        }
-
         /// <summary>
         /// Executes a script file at the specified path.
         /// </summary>
@@ -338,11 +314,16 @@ await this.consoleReadLine.ReadCommandLine(
                 {
                     Console.Write(Environment.NewLine);
 
-                    await this.powerShellContext.ExecuteScriptString(
-                        commandString,
-                        false,
-                        true,
-                        true);
+                    var unusedTask =
+                        this.powerShellContext
+                            .ExecuteScriptString(
+                                commandString,
+                                false,
+                                true,
+                                true)
+                            .ConfigureAwait(false);
+
+                    break;
                 }
             }
             while (!cancellationToken.IsCancellationRequested);
@@ -459,6 +440,37 @@ private void PowerShellContext_DebuggerResumed(object sender, System.Management.
             this.CancelReadLoop();
         }
 
+        private void PowerShellContext_ExecutionStatusChanged(object sender, ExecutionStatusChangedEventArgs eventArgs)
+        {
+            if (this.EnableConsoleRepl)
+            {
+                // Any command which writes output to the host will affect
+                // the display of the prompt
+                if (eventArgs.ExecutionOptions.WriteOutputToHost ||
+                    eventArgs.ExecutionOptions.InterruptCommandPrompt)
+                {
+                    if (eventArgs.ExecutionStatus != ExecutionStatus.Running)
+                    {
+                        // Execution has completed, start the input prompt
+                        this.StartReadLoop();
+                    }
+                    else
+                    {
+                        // A new command was started, cancel the input prompt
+                        this.CancelReadLoop();
+                    }
+                }
+                else if (
+                    eventArgs.ExecutionOptions.WriteErrorsToHost &&
+                    (eventArgs.ExecutionStatus == ExecutionStatus.Failed ||
+                     eventArgs.HadErrors))
+                {
+                    this.CancelReadLoop();
+                    this.StartReadLoop();
+                }
+            }
+        }
+
         #endregion
     }
 }

src/PowerShellEditorServices/Session/ExecutionOptions.cs

@@ -0,0 +1,59 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+namespace Microsoft.PowerShell.EditorServices
+{
+    /// <summary>
+    /// Defines options for the execution of a command.
+    /// </summary>
+    public class ExecutionOptions
+    {
+        #region Properties
+
+        /// <summary>
+        /// Gets or sets a boolean that determines whether command output
+        /// should be written to the host.
+        /// </summary>
+        public bool WriteOutputToHost { get; set; }
+
+        /// <summary>
+        /// Gets or sets a boolean that determines whether command errors
+        /// should be written to the host.
+        /// </summary>
+        public bool WriteErrorsToHost { get; set; }
+
+        /// <summary>
+        /// Gets or sets a boolean that determines whether the executed
+        /// command should be added to the command history.
+        /// </summary>
+        public bool AddToHistory { get; set; }
+
+        /// <summary>
+        /// Gets or sets a boolean that determines whether the execution
+        /// of the command should interrupt the command prompt.  Should
+        /// only be set if WriteOutputToHost is false but the command
+        /// should still interrupt the command prompt.
+        /// </summary>
+        public bool InterruptCommandPrompt { get; set; }
+
+        #endregion
+
+        #region Constructors
+
+        /// <summary>
+        /// Creates an instance of the ExecutionOptions class with
+        /// default settings configured.
+        /// </summary>
+        public ExecutionOptions()
+        {
+            this.WriteOutputToHost = true;
+            this.WriteErrorsToHost = true;
+            this.AddToHistory = false;
+            this.InterruptCommandPrompt = false;
+        }
+
+        #endregion
+    }
+}

src/PowerShellEditorServices/Session/ExecutionStatus.cs

@@ -0,0 +1,39 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+namespace Microsoft.PowerShell.EditorServices
+{
+    /// <summary>
+    /// Enumerates the possible execution results that can occur after
+    /// executing a command or script.
+    /// </summary>
+    public enum ExecutionStatus
+    {
+        /// <summary>
+        /// Indicates that execution has not yet started.
+        /// </summary>
+        Pending,
+
+        /// <summary>
+        /// Indicates that the command is executing.
+        /// </summary>
+        Running,
+
+        /// <summary>
+        /// Indicates that execution has failed.
+        /// </summary>
+        Failed,
+
+        /// <summary>
+        /// Indicates that execution was aborted by the user.
+        /// </summary>
+        Aborted,
+
+        /// <summary>
+        /// Indicates that execution completed successfully.
+        /// </summary>
+        Completed
+    }
+}

src/PowerShellEditorServices/Session/ExecutionStatusChangedEventArgs.cs

@@ -0,0 +1,52 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+namespace Microsoft.PowerShell.EditorServices
+{
+    /// <summary>
+    /// Contains details about an executed 
+    /// </summary>
+    public class ExecutionStatusChangedEventArgs
+    {
+        #region Properties
+
+        /// <summary>
+        /// Gets the options used when the command was executed.
+        /// </summary>
+        public ExecutionOptions ExecutionOptions { get; private set; }
+
+        /// <summary>
+        /// Gets the command execution's current status.
+        /// </summary>
+        public ExecutionStatus ExecutionStatus { get; private set; }
+
+        /// <summary>
+        /// If true, the command execution had errors.
+        /// </summary>
+        public bool HadErrors { get; private set; }
+
+        #endregion
+
+        #region Constructors
+
+        /// <summary>
+        /// Creates an instance of the ExecutionStatusChangedEventArgs class.
+        /// </summary>
+        /// <param name="executionStatus">The command execution's current status.</param>
+        /// <param name="executionOptions">The options used when the command was executed.</param>
+        /// <param name="hadErrors">If execution has completed, indicates whether there were errors.</param>
+        public ExecutionStatusChangedEventArgs(
+            ExecutionStatus executionStatus,
+            ExecutionOptions executionOptions,
+            bool hadErrors)
+        {
+            this.ExecutionStatus = executionStatus;
+            this.ExecutionOptions = executionOptions;
+            this.HadErrors = hadErrors || (executionStatus == ExecutionStatus.Failed);
+        }
+
+        #endregion
+    }
+}