Merge pull request #11904 from drognanar/fixreploutput2

Print remaining REPL output if it crashes in VS host

src/Interactive/Features/Interactive/Core/InteractiveHost.RemoteService.cs

@@ -20,7 +20,8 @@ internal sealed class RemoteService
             // output pumping threads (stream output from stdout/stderr of the host process to the output/errorOutput writers)
             private Thread _readOutputThread;           // nulled on dispose
             private Thread _readErrorOutputThread;      // nulled on dispose
-            private InteractiveHost _host;       // nulled on dispose
+            private InteractiveHost _host;              // nulled on dispose
+            private bool _disposing;                    // set to true on dispose
 
             internal RemoteService(InteractiveHost host, Process process, int processId, Service service)
             {
@@ -29,6 +30,7 @@ internal RemoteService(InteractiveHost host, Process process, int processId, Ser
                 Debug.Assert(service != null);
 
                 _host = host;
+                _disposing = false;
                 this.Process = process;
                 _processId = processId;
                 this.Service = service;
@@ -61,7 +63,7 @@ internal void HookAutoRestartEvent()
                         {
                             Process.Exited -= localHandler;
 
-                            if (!IsDisposed)
+                            if (!_disposing)
                             {
                                 await _host.OnProcessExited(Process).ConfigureAwait(false);
                             }
@@ -73,7 +75,7 @@ internal void HookAutoRestartEvent()
                     }
                 };
 
-                // hook the even only once per process:
+                // hook the event only once per process:
                 if (Interlocked.Exchange(ref processExitHandling, ProcessExitHooked) == 0)
                 {
                     Process.Exited += localHandler;
@@ -110,12 +112,10 @@ private void ReadOutput(bool error)
                 }
             }
 
-            private bool IsDisposed => _host == null;
-
             internal void Dispose(bool joinThreads)
             {
-                // null the host so that we don't attempt to restart or write to the buffer anymore:
-                _host = null;
+                // set _disposing so that we don't attempt restart the host anymore:
+                _disposing = true;
 
                 InitiateTermination(Process, _processId);
 
@@ -147,6 +147,9 @@ internal void Dispose(bool joinThreads)
                     }
                 }
 
+                // null the host so that we don't attempt to write to the buffer anymore:
+                _host = null;
+
                 _readOutputThread = _readErrorOutputThread = null;
             }
 

src/Interactive/Features/Interactive/Core/InteractiveHost.cs

@@ -76,7 +76,7 @@ internal Process TryGetProcess()
 
         internal Service TryGetService()
         {
-            var initializedService = TryGetOrCreateRemoteServiceAsync().Result;
+            var initializedService = TryGetOrCreateRemoteServiceAsync(processPendingOutput: false).Result;
             return initializedService.ServiceOpt?.Service;
         }
 
@@ -312,7 +312,7 @@ private LazyRemoteService CreateRemoteService(InteractiveHostOptions options, bo
         private Task OnProcessExited(Process process)
         {
             ReportProcessExited(process);
-            return TryGetOrCreateRemoteServiceAsync();
+            return TryGetOrCreateRemoteServiceAsync(processPendingOutput: true);
         }
 
         private void ReportProcessExited(Process process)
@@ -333,7 +333,7 @@ private void ReportProcessExited(Process process)
             }
         }
 
-        private async Task<InitializedRemoteService> TryGetOrCreateRemoteServiceAsync()
+        private async Task<InitializedRemoteService> TryGetOrCreateRemoteServiceAsync(bool processPendingOutput)
         {
             try
             {
@@ -357,7 +357,7 @@ private async Task<InitializedRemoteService> TryGetOrCreateRemoteServiceAsync()
                     if (previousService == currentRemoteService)
                     {
                         // we replaced the service whose process we know is dead:
-                        currentRemoteService.Dispose(joinThreads: false);
+                        currentRemoteService.Dispose(processPendingOutput);
                         currentRemoteService = newService;
                     }
                     else
@@ -387,7 +387,7 @@ private async Task<TResult> Async<TResult>(Action<Service, RemoteAsyncOperation<
         {
             try
             {
-                var initializedService = await TryGetOrCreateRemoteServiceAsync().ConfigureAwait(false);
+                var initializedService = await TryGetOrCreateRemoteServiceAsync(processPendingOutput: false).ConfigureAwait(false);
                 if (initializedService.ServiceOpt == null)
                 {
                     return default(TResult);
@@ -434,7 +434,7 @@ public async Task<RemoteExecutionResult> ResetAsync(InteractiveHostOptions optio
                     oldService.Dispose(joinThreads: false);
                 }
 
-                var initializedService = await TryGetOrCreateRemoteServiceAsync().ConfigureAwait(false);
+                var initializedService = await TryGetOrCreateRemoteServiceAsync(processPendingOutput: false).ConfigureAwait(false);
                 if (initializedService.ServiceOpt == null)
                 {
                     return default(RemoteExecutionResult);