Fixes #4139. Application.Run<T> isn't initializing properly by setting the Application.ForceDriver property (#4142)

* Fixes #4139. Application.Run<T> isn't initializing properly by setting the Application.ForceDriver property

* Trying fix unit tests

* Only to force again CI tests because I haven't errors locally

* This should pass, unless RunningUnitTests is set to false somewhere

* Fix Unix unit tests and failures via ReSharper

* Changes suggested by @tig

* Prevent empty string

* Centralize all the entry logic in the InternalInit method

* Change GetDriverTypes to return a tuple

Author: BDisp

Examples/UICatalog/Properties/launchSettings.json

@@ -12,6 +12,10 @@
       "commandName": "Project",
       "commandLineArgs": "--driver WindowsDriver"
     },
+    "UICatalog --driver v2": {
+      "commandName": "Project",
+      "commandLineArgs": "--driver v2 -dl Trace"
+    },
     "UICatalog --driver v2win": {
       "commandName": "Project",
       "commandLineArgs": "--driver v2win -dl Trace"
@@ -32,6 +36,18 @@
       "commandLineArgs": "dotnet UICatalog.dll --driver NetDriver",
       "distributionName": ""
     },
+    "WSL: UICatalog --driver v2": {
+      "commandName": "Executable",
+      "executablePath": "wsl",
+      "commandLineArgs": "dotnet UICatalog.dll --driver v2",
+      "distributionName": ""
+    },
+    "WSL: UICatalog --driver v2net": {
+      "commandName": "Executable",
+      "executablePath": "wsl",
+      "commandLineArgs": "dotnet UICatalog.dll --driver v2net",
+      "distributionName": ""
+    },
     "Benchmark All": {
       "commandName": "Project",
       "commandLineArgs": "--benchmark"

Examples/UICatalog/UICatalog.cs

@@ -54,7 +54,7 @@ namespace UICatalog;
 /// </remarks>
 public class UICatalog
 {
-    private static string _forceDriver = string.Empty;
+    private static string? _forceDriver = null;
 
     public static string LogFilePath { get; set; } = string.Empty;
     public static LoggingLevelSwitch LogLevelSwitch { get; } = new ();
@@ -77,11 +77,7 @@ private static int Main (string [] args)
 
         // If no driver is provided, the default driver is used.
         Option<string> driverOption = new Option<string> ("--driver", "The IConsoleDriver to use.").FromAmong (
-             Application.GetDriverTypes ()
-                        .Where (d => !typeof (IConsoleDriverFacade).IsAssignableFrom (d))
-                        .Select (d => d!.Name)
-                        .Union (["v2", "v2win", "v2net"])
-                        .ToArray ()
+             Application.GetDriverTypes ().Item2.ToArray ()!
             );
         driverOption.AddAlias ("-d");
         driverOption.AddAlias ("--d");

Terminal.Gui/App/Application.Initialization.cs

@@ -40,11 +40,6 @@ public static partial class Application // Initialization (Init/Shutdown)
     [RequiresDynamicCode ("AOT")]
     public static void Init (IConsoleDriver? driver = null, string? driverName = null)
     {
-        if (driverName?.StartsWith ("v2") ?? false)
-        {
-            ApplicationImpl.ChangeInstance (new ApplicationV2 ());
-        }
-
         ApplicationImpl.Instance.Init (driver, driverName);
     }
 
@@ -83,12 +78,6 @@ internal static void InternalInit (
             ResetState (ignoreDisposed: true);
         }
 
-        Debug.Assert (Navigation is null);
-        Navigation = new ();
-
-        Debug.Assert(Popover is null);
-        Popover = new ();
-
         // For UnitTests
         if (driver is { })
         {
@@ -105,8 +94,6 @@ internal static void InternalInit (
             }
         }
 
-        AddKeyBindings ();
-
         // Ignore Configuration for ForceDriver if driverName is specified
         if (!string.IsNullOrEmpty (driverName))
         {
@@ -130,13 +117,21 @@ internal static void InternalInit (
             }
             else
             {
-                List<Type?> drivers = GetDriverTypes ();
+                (List<Type?> drivers, List<string?> driverTypeNames) = GetDriverTypes ();
                 Type? driverType = drivers.FirstOrDefault (t => t!.Name.Equals (ForceDriver, StringComparison.InvariantCultureIgnoreCase));
 
                 if (driverType is { })
                 {
                     Driver = (IConsoleDriver)Activator.CreateInstance (driverType)!;
                 }
+                else if (ForceDriver?.StartsWith ("v2") ?? false)
+                {
+                    ApplicationImpl.ChangeInstance (new ApplicationV2 ());
+                    ApplicationImpl.Instance.Init (driver, ForceDriver);
+                    Debug.Assert (Driver is { });
+
+                    return;
+                }
                 else
                 {
                     throw new ArgumentException (
@@ -146,6 +141,14 @@ internal static void InternalInit (
             }
         }
 
+        Debug.Assert (Navigation is null);
+        Navigation = new ();
+
+        Debug.Assert (Popover is null);
+        Popover = new ();
+
+        AddKeyBindings ();
+
         try
         {
             MainLoop = Driver!.Init ();
@@ -201,10 +204,10 @@ internal static void UnsubscribeDriverEvents ()
     private static void Driver_KeyUp (object? sender, Key e) { RaiseKeyUpEvent (e); }
     private static void Driver_MouseEvent (object? sender, MouseEventArgs e) { RaiseMouseEvent (e); }
 
-    /// <summary>Gets of list of <see cref="IConsoleDriver"/> types that are available.</summary>
+    /// <summary>Gets of list of <see cref="IConsoleDriver"/> types and type names that are available.</summary>
     /// <returns></returns>
     [RequiresUnreferencedCode ("AOT")]
-    public static List<Type?> GetDriverTypes ()
+    public static (List<Type?>, List<string?>) GetDriverTypes ()
     {
         // use reflection to get the list of drivers
         List<Type?> driverTypes = new ();
@@ -220,7 +223,13 @@ internal static void UnsubscribeDriverEvents ()
             }
         }
 
-        return driverTypes;
+        List<string?> driverTypeNames = driverTypes
+                                        .Where (d => !typeof (IConsoleDriverFacade).IsAssignableFrom (d))
+                                        .Select (d => d!.Name)
+                                        .Union (["v2", "v2win", "v2net"])
+                                        .ToList ()!;
+
+        return (driverTypes, driverTypeNames);
     }
 
     /// <summary>Shutdown an application initialized with <see cref="Init"/>.</summary>

Terminal.Gui/App/ApplicationImpl.cs

@@ -34,7 +34,7 @@ public static void ChangeInstance (IApplication newApplication)
     [RequiresDynamicCode ("AOT")]
     public virtual void Init (IConsoleDriver? driver = null, string? driverName = null)
     {
-        Application.InternalInit (driver, driverName);
+        Application.InternalInit (driver, string.IsNullOrWhiteSpace (driverName) ? Application.ForceDriver : driverName);
     }
 
     /// <summary>
@@ -85,7 +85,12 @@ public virtual T Run<T> (Func<Exception, bool>? errorHandler = null, IConsoleDri
         if (!Application.Initialized)
         {
             // Init() has NOT been called.
-            Application.InternalInit (driver, null, true);
+            Application.InternalInit (driver, Application.ForceDriver, true);
+        }
+
+        if (Instance is ApplicationV2)
+        {
+            return Instance.Run<T> (errorHandler, driver);
         }
 
         var top = new T ();
@@ -227,6 +232,8 @@ public virtual void Shutdown ()
 
             Application.OnInitializedChanged (this, new (in init));
         }
+
+        _lazyInstance = new (() => new ApplicationImpl ());
     }
 
     /// <inheritdoc />

Terminal.Gui/Drivers/NetDriver/NetEvents.cs

@@ -19,6 +19,11 @@ public NetEvents (IConsoleDriver consoleDriver)
     {
         _consoleDriver = consoleDriver ?? throw new ArgumentNullException (nameof (consoleDriver));
 
+        if (ConsoleDriver.RunningUnitTests)
+        {
+            return;
+        }
+
         Task.Run (() =>
         {
             try
@@ -29,7 +34,8 @@ public NetEvents (IConsoleDriver consoleDriver)
             { }
         }, _netEventsDisposed.Token);
 
-        Task.Run (() => {
+        Task.Run (() =>
+        {
             try
             {
                 CheckWindowSizeChange ();

Terminal.Gui/Drivers/V2/ConsoleDriverFacade.cs

@@ -64,7 +64,19 @@ private void CreateClipboard ()
     }
 
     /// <summary>Gets the location and size of the terminal screen.</summary>
-    public Rectangle Screen => new (new (0, 0), _output.GetWindowSize ());
+    public Rectangle Screen
+    {
+        get
+        {
+            if (ConsoleDriver.RunningUnitTests)
+            {
+                // In unit tests, we don't have a real output, so we return an empty rectangle.
+                return Rectangle.Empty;
+            }
+
+            return new (new (0, 0), _output.GetWindowSize ());
+        }
+    }
 
     /// <summary>
     ///     Gets or sets the clip rectangle that <see cref="AddRune(Rune)"/> and <see cref="AddStr(string)"/> are subject

Terminal.Gui/Drivers/V2/NetInput.cs

@@ -17,6 +17,12 @@ public class NetInput : ConsoleInput<ConsoleKeyInfo>, INetInput
     public NetInput ()
     {
         Logging.Logger.LogInformation ($"Creating {nameof (NetInput)}");
+
+        if (ConsoleDriver.RunningUnitTests)
+        {
+            return;
+        }
+
         PlatformID p = Environment.OSVersion.Platform;
 
         if (p == PlatformID.Win32NT || p == PlatformID.Win32S || p == PlatformID.Win32Windows)
@@ -39,7 +45,15 @@ public NetInput ()
     }
 
     /// <inheritdoc/>
-    protected override bool Peek () { return Console.KeyAvailable; }
+    protected override bool Peek ()
+    {
+        if (ConsoleDriver.RunningUnitTests)
+        {
+            return false;
+        }
+
+        return Console.KeyAvailable;
+    }
 
     /// <inheritdoc/>
     protected override IEnumerable<ConsoleKeyInfo> Read ()

Terminal.Gui/Drivers/V2/NetOutput.cs

@@ -47,6 +47,11 @@ public void Write (ReadOnlySpan<char> text)
     /// <inheritdoc/>
     public void Write (IOutputBuffer buffer)
     {
+        if (ConsoleDriver.RunningUnitTests)
+        {
+            return;
+        }
+
         if (Console.WindowHeight < 1
             || buffer.Contents.Length != buffer.Rows * buffer.Cols
             || buffer.Rows != Console.WindowHeight)
@@ -197,7 +202,16 @@ public void Write (IOutputBuffer buffer)
     }
 
     /// <inheritdoc/>
-    public Size GetWindowSize () { return new (Console.WindowWidth, Console.WindowHeight); }
+    public Size GetWindowSize ()
+    {
+        if (ConsoleDriver.RunningUnitTests)
+        {
+            // For unit tests, we return a default size.
+            return Size.Empty;
+        }
+
+        return new (Console.WindowWidth, Console.WindowHeight);
+    }
 
     private void WriteToConsole (StringBuilder output, ref int lastCol, int row, ref int outputWidth)
     {

Terminal.Gui/Drivers/V2/WindowSizeMonitor.cs

@@ -20,6 +20,11 @@ public WindowSizeMonitor (IConsoleOutput consoleOut, IOutputBuffer outputBuffer)
     /// <inheritdoc/>
     public bool Poll ()
     {
+        if (ConsoleDriver.RunningUnitTests)
+        {
+            return false;
+        }
+
         Size size = _consoleOut.GetWindowSize ();
 
         if (size != _lastSize)

Terminal.Gui/Drivers/V2/WindowsInput.cs

@@ -38,6 +38,12 @@ out uint lpNumberOfEventsRead
     public WindowsInput ()
     {
         Logging.Logger.LogInformation ($"Creating {nameof (WindowsInput)}");
+
+        if (ConsoleDriver.RunningUnitTests)
+        {
+            return;
+        }
+
         _inputHandle = GetStdHandle (STD_INPUT_HANDLE);
 
         GetConsoleMode (_inputHandle, out uint v);
@@ -110,5 +116,13 @@ protected override bool Peek ()
         }
     }
 
-    public override void Dispose () { SetConsoleMode (_inputHandle, _originalConsoleMode); }
+    public override void Dispose ()
+    {
+        if (ConsoleDriver.RunningUnitTests)
+        {
+            return;
+        }
+
+        SetConsoleMode (_inputHandle, _originalConsoleMode);
+    }
 }