fix: deadlock when calling Environment.Exit (#301)

Author: thomaslevesque

CHANGELOG.md

@@ -2,6 +2,11 @@
 
 [See unreleased changes][unreleased].
 
+## [v2.4.3]
+* Fix [#292] by [@thomaslevesque] - fix deadlock when `Environment.Exit` is called
+
+[#292]: https://github.com/natemcmaster/CommandLineUtils/issues/292
+
 ## [v2.4.2]
 * Fix [#286] - fix deadlock in CTRL+C handling on Windows
 
@@ -384,6 +389,7 @@ Other:
 [@sebastienros]: https://github.com/sebastienros
 [@SteveBenz]: https://github.com/SteveBenz
 [@TheConstructor]: https://github.com/TheConstructor
+[@thomaslevesque]: https://github.com/thomaslevesque
 [@vpkopylov]: https://github.com/vpkopylov
 
 [unreleased]: https://github.com/natemcmaster/CommandLineUtils/compare/v2.4.0...HEAD

src/CommandLineUtils/CommandLineApplication.cs

@@ -886,22 +886,10 @@ void cancelHandler(object o, ConsoleCancelEventArgs e)
                 e.Cancel = true;
             }
 
-#if !NETSTANDARD1_6
-            void processExitHandler(object o, EventArgs e)
-            {
-                handlerCancellationTokenSource.Cancel();
-                handlerCompleted.Wait();
-            }
-#endif
-
             try
             {
                 // blocks .NET's CTRL+C handler from completing until after async completions are done
                 _context.Console.CancelKeyPress += cancelHandler;
-#if !NETSTANDARD1_6
-                // blocks .NET's process unloading from completing until after async completions are done
-                AppDomain.CurrentDomain.ProcessExit += processExitHandler;
-#endif
 
                 return await command._handler(handlerCancellationTokenSource.Token);
             }
@@ -912,9 +900,6 @@ void processExitHandler(object o, EventArgs e)
             finally
             {
                 _context.Console.CancelKeyPress -= cancelHandler;
-#if !NETSTANDARD1_6
-                AppDomain.CurrentDomain.ProcessExit -= processExitHandler;
-#endif
                 handlerCompleted.Set();
             }
         }

src/Hosting.CommandLine/Internal/CommandLineLifetime.cs

@@ -20,7 +20,6 @@ internal class CommandLineLifetime : IHostLifetime, IDisposable
         private readonly ICommandLineService _cliService;
         private readonly IConsole _console;
         private readonly IUnhandledExceptionHandler? _unhandledExceptionHandler;
-        private readonly ManualResetEvent _blockProcessExit = new ManualResetEvent(false);
 
         /// <summary>
         ///     Creates a new instance.
@@ -81,13 +80,6 @@ public Task WaitForStartAsync(CancellationToken cancellationToken)
                 }
             });
 
-            AppDomain.CurrentDomain.ProcessExit += (_, __) =>
-            {
-                _applicationLifetime.StopApplication();
-                // Ensures services are disposed before the application exits.
-                _blockProcessExit.WaitOne();
-            };
-
             // Capture CTRL+C and prevent it from immediately force killing the app.
             _console.CancelKeyPress += (_, e) =>
             {
@@ -100,7 +92,6 @@ public Task WaitForStartAsync(CancellationToken cancellationToken)
 
         public void Dispose()
         {
-            _blockProcessExit.Set();
         }
     }
 }