Fixes #4243 - `ConsoleDriverFacade.CreateClipboard` now honors `FakeDriver.FakeBehaviors.UseFakeClipboard` (#4244)

* updatd ConsoleDriverFacade.CreateClipboard to honor FakeDriver.FakeBehaviors.UseFakeClipboard

* Code cleanup of fake driver v2

Terminal.Gui/App/Clipboard/Clipboard.cs

@@ -1,5 +1,4 @@
-using System.Diagnostics;
-
+#nullable enable
 namespace Terminal.Gui.App;
 
 /// <summary>Provides cut, copy, and paste support for the OS clipboard.</summary>
@@ -20,10 +19,10 @@ namespace Terminal.Gui.App;
 /// </remarks>
 public static class Clipboard
 {
-    private static string _contents = string.Empty;
+    private static string? _contents = string.Empty;
 
     /// <summary>Gets (copies from) or sets (pastes to) the contents of the OS clipboard.</summary>
-    public static string Contents
+    public static string? Contents
     {
         get
         {
@@ -31,13 +30,8 @@ public static class Clipboard
             {
                 if (IsSupported)
                 {
-                    string clipData = Application.Driver?.Clipboard.GetClipboardData ();
-
-                    if (clipData is null)
-                    {
-                        // throw new InvalidOperationException ($"{Application.Driver?.GetType ().Name}.GetClipboardData returned null instead of string.Empty");
-                        clipData = string.Empty;
-                    }
+                    // throw new InvalidOperationException ($"{Application.Driver?.GetType ().Name}.GetClipboardData returned null instead of string.Empty");
+                    string? clipData = Application.Driver?.Clipboard?.GetClipboardData () ?? string.Empty;
 
                     _contents = clipData;
                 }
@@ -55,12 +49,9 @@ public static class Clipboard
             {
                 if (IsSupported)
                 {
-                    if (value is null)
-                    {
-                        value = string.Empty;
-                    }
+                    value ??= string.Empty;
 
-                    Application.Driver?.Clipboard.SetClipboardData (value);
+                    Application.Driver?.Clipboard?.SetClipboardData (value);
                 }
 
                 _contents = value;
@@ -74,126 +65,5 @@ public static class Clipboard
 
     /// <summary>Returns true if the environmental dependencies are in place to interact with the OS clipboard.</summary>
     /// <remarks></remarks>
-    public static bool IsSupported => Application.Driver?.Clipboard.IsSupported ?? false;
-
-    /// <summary>Copies the _contents of the OS clipboard to <paramref name="result"/> if possible.</summary>
-    /// <param name="result">The _contents of the OS clipboard if successful, <see cref="string.Empty"/> if not.</param>
-    /// <returns><see langword="true"/> the OS clipboard was retrieved, <see langword="false"/> otherwise.</returns>
-    public static bool TryGetClipboardData (out string result)
-    {
-        if (IsSupported && Application.Driver!.Clipboard.TryGetClipboardData (out result))
-        {
-            _contents = result;
-
-            return true;
-        }
-
-        result = string.Empty;
-
-        return false;
-    }
-
-    /// <summary>Pastes the <paramref name="text"/> to the OS clipboard if possible.</summary>
-    /// <param name="text">The text to paste to the OS clipboard.</param>
-    /// <returns><see langword="true"/> the OS clipboard was set, <see langword="false"/> otherwise.</returns>
-    public static bool TrySetClipboardData (string text)
-    {
-        if (IsSupported && Application.Driver!.Clipboard.TrySetClipboardData (text))
-        {
-            _contents = text;
-
-            return true;
-        }
-
-        return false;
-    }
-}
-
-/// <summary>
-///     Helper class for console drivers to invoke shell commands to interact with the clipboard. Used primarily by
-///     CursesDriver, but also used in Unit tests which is why it is in IConsoleDriver.cs.
-/// </summary>
-internal static class ClipboardProcessRunner
-{
-    public static (int exitCode, string result) Bash (
-        string commandLine,
-        string inputText = "",
-        bool waitForOutput = false
-    )
-    {
-        var arguments = $"-c \"{commandLine}\"";
-        (int exitCode, string result) = Process ("bash", arguments, inputText, waitForOutput);
-
-        return (exitCode, result.TrimEnd ());
-    }
-
-    public static bool DoubleWaitForExit (this Process process)
-    {
-        bool result = process.WaitForExit (500);
-
-        if (result)
-        {
-            process.WaitForExit ();
-        }
-
-        return result;
-    }
-
-    public static bool FileExists (this string value) { return !string.IsNullOrEmpty (value) && !value.Contains ("not found"); }
-
-    public static (int exitCode, string result) Process (
-        string cmd,
-        string arguments,
-        string input = null,
-        bool waitForOutput = true
-    )
-    {
-            var output = string.Empty;
-
-        using (var process = new Process
-               {
-                   StartInfo = new()
-                   {
-                       FileName = cmd,
-                       Arguments = arguments,
-                       RedirectStandardOutput = true,
-                       RedirectStandardError = true,
-                       RedirectStandardInput = true,
-                       UseShellExecute = false,
-                       CreateNoWindow = true
-                   }
-               })
-        {
-            TaskCompletionSource<bool> eventHandled = new ();
-            process.Start ();
-
-            if (!string.IsNullOrEmpty (input))
-            {
-                process.StandardInput.Write (input);
-                process.StandardInput.Close ();
-            }
-
-            if (!process.WaitForExit (5000))
-            {
-                var timeoutError =
-                    $@"Process timed out. Command line: {process.StartInfo.FileName} {process.StartInfo.Arguments}.";
-
-                throw new TimeoutException (timeoutError);
-            }
-
-            if (waitForOutput && process.StandardOutput.Peek () != -1)
-            {
-                output = process.StandardOutput.ReadToEnd ();
-            }
-
-            if (process.ExitCode > 0)
-            {
-                output = $@"Process failed to run. Command line: {cmd} {arguments}.
-										Output: {output}
-										Error: {process.StandardError.ReadToEnd ()}";
-            }
-
-            return (process.ExitCode, output);
-        }
-    }
-}
+    public static bool IsSupported => Application.Driver?.Clipboard?.IsSupported ?? false;
+}

Terminal.Gui/App/Clipboard/ClipboardProcessRunner.cs

@@ -0,0 +1,79 @@
+#nullable enable
+using System.Diagnostics;
+
+namespace Terminal.Gui.App;
+
+/// <summary>
+///     Helper class for console drivers to invoke shell commands to interact with the clipboard. Used primarily by
+///     CursesDriver, but also used in Unit tests which is why it is in IConsoleDriver.cs.
+/// </summary>
+internal static class ClipboardProcessRunner
+{
+    public static (int exitCode, string result) Bash (
+        string commandLine,
+        string inputText = "",
+        bool waitForOutput = false
+    )
+    {
+        var arguments = $"-c \"{commandLine}\"";
+        (int exitCode, string result) = Process ("bash", arguments, inputText, waitForOutput);
+
+        return (exitCode, result.TrimEnd ());
+    }
+
+    public static bool FileExists (this string value) { return !string.IsNullOrEmpty (value) && !value.Contains ("not found"); }
+
+    public static (int exitCode, string result) Process (
+        string cmd,
+        string arguments,
+        string? input = null,
+        bool waitForOutput = true
+    )
+    {
+        var output = string.Empty;
+
+        using var process = new Process ();
+
+        process.StartInfo = new()
+        {
+            FileName = cmd,
+            Arguments = arguments,
+            RedirectStandardOutput = true,
+            RedirectStandardError = true,
+            RedirectStandardInput = true,
+            UseShellExecute = false,
+            CreateNoWindow = true
+        };
+
+        TaskCompletionSource<bool> eventHandled = new ();
+        process.Start ();
+
+        if (!string.IsNullOrEmpty (input))
+        {
+            process.StandardInput.Write (input);
+            process.StandardInput.Close ();
+        }
+
+        if (!process.WaitForExit (5000))
+        {
+            var timeoutError =
+                $@"Process timed out. Command line: {process.StartInfo.FileName} {process.StartInfo.Arguments}.";
+
+            throw new TimeoutException (timeoutError);
+        }
+
+        if (waitForOutput && process.StandardOutput.Peek () != -1)
+        {
+            output = process.StandardOutput.ReadToEnd ();
+        }
+
+        if (process.ExitCode > 0)
+        {
+            output = $@"Process failed to run. Command line: {cmd} {arguments}.
+										Output: {output}
+										Error: {process.StandardError.ReadToEnd ()}";
+        }
+
+        return (process.ExitCode, output);
+    }
+}

Terminal.Gui/Drivers/FakeDriver/FakeDriver.cs

@@ -1,4 +1,5 @@
-//
+#nullable enable
+//
 // FakeDriver.cs: A fake IConsoleDriver for unit tests. 
 //
 
@@ -36,7 +37,7 @@ public class FakeDriver : ConsoleDriver
         public bool UseFakeClipboard { get; internal set; }
     }
 
-    public static Behaviors FakeBehaviors = new ();
+    public static Behaviors FakeBehaviors { get; } = new ();
     public override bool SupportsTrueColor => false;
 
     /// <inheritdoc />
@@ -47,8 +48,8 @@ public class FakeDriver : ConsoleDriver
 
     public FakeDriver ()
     {
-        Cols = FakeConsole.WindowWidth = FakeConsole.BufferWidth = FakeConsole.WIDTH;
-        Rows = FakeConsole.WindowHeight = FakeConsole.BufferHeight = FakeConsole.HEIGHT;
+        base.Cols = FakeConsole.WindowWidth = FakeConsole.BufferWidth = FakeConsole.WIDTH;
+        base.Rows = FakeConsole.WindowHeight = FakeConsole.BufferHeight = FakeConsole.HEIGHT;
 
         if (FakeBehaviors.UseFakeClipboard)
         {
@@ -87,7 +88,7 @@ public class FakeDriver : ConsoleDriver
         FakeConsole.Clear ();
     }
 
-    private FakeMainLoop _mainLoopDriver;
+    private FakeMainLoop? _mainLoopDriver;
 
     public override MainLoop Init ()
     {
@@ -124,7 +125,7 @@ public class FakeDriver : ConsoleDriver
 
         for (int row = top; row < rows; row++)
         {
-            if (!_dirtyLines [row])
+            if (!_dirtyLines! [row])
             {
                 continue;
             }
@@ -144,7 +145,7 @@ public class FakeDriver : ConsoleDriver
 
                 for (; col < cols; col++)
                 {
-                    if (!Contents [row, col].IsDirty)
+                    if (!Contents! [row, col].IsDirty)
                     {
                         if (output.Length > 0)
                         {
@@ -168,7 +169,7 @@ public class FakeDriver : ConsoleDriver
                         lastCol = col;
                     }
 
-                    Attribute attr = Contents [row, col].Attribute.Value;
+                    Attribute attr = Contents [row, col].Attribute!.Value;
 
                     // Performance: Only send the escape sequence if the attribute has changed.
                     if (attr != redrawAttr)
@@ -209,18 +210,18 @@ public class FakeDriver : ConsoleDriver
 
         //SetCursorVisibility (savedVisibility);
 
-        void WriteToConsole (StringBuilder output, ref int lastCol, int row, ref int outputWidth)
+        void WriteToConsole (StringBuilder outputSb, ref int lastColumn, int row, ref int outputWidth)
         {
             FakeConsole.CursorTop = row;
-            FakeConsole.CursorLeft = lastCol;
+            FakeConsole.CursorLeft = lastColumn;
 
-            foreach (char c in output.ToString ())
+            foreach (char c in outputSb.ToString ())
             {
                 FakeConsole.Write (c);
             }
 
-            output.Clear ();
-            lastCol += outputWidth;
+            outputSb.Clear ();
+            lastColumn += outputWidth;
             outputWidth = 0;
         }
 
@@ -506,7 +507,7 @@ public class FakeDriver : ConsoleDriver
 
     public class FakeClipboard : ClipboardBase
     {
-        public Exception FakeException;
+        public Exception? FakeException { get; set; }
 
         private readonly bool _isSupportedAlwaysFalse;
         private string _contents = string.Empty;
@@ -536,19 +537,14 @@ public class FakeDriver : ConsoleDriver
             return _contents;
         }
 
-        protected override void SetClipboardDataImpl (string text)
+        protected override void SetClipboardDataImpl (string? text)
         {
-            if (text is null)
-            {
-                throw new ArgumentNullException (nameof (text));
-            }
-
             if (FakeException is { })
             {
                 throw FakeException;
             }
 
-            _contents = text;
+            _contents = text ?? throw new ArgumentNullException (nameof (text));
         }
     }
 

Terminal.Gui/Drivers/V2/ConsoleDriverFacade.cs

@@ -1,5 +1,5 @@
-using System.Runtime.InteropServices;
-using Microsoft.Extensions.Logging;
+#nullable enable
+using System.Runtime.InteropServices;
 
 namespace Terminal.Gui.Drivers;
 
@@ -11,7 +11,7 @@ internal class ConsoleDriverFacade<T> : IConsoleDriver, IConsoleDriverFacade
     private CursorVisibility _lastCursor = CursorVisibility.Default;
 
     /// <summary>The event fired when the terminal is resized.</summary>
-    public event EventHandler<SizeChangedEventArgs> SizeChanged;
+    public event EventHandler<SizeChangedEventArgs>? SizeChanged;
 
     public IInputProcessor InputProcessor { get; }
     public IOutputBuffer OutputBuffer => _outputBuffer;
@@ -48,6 +48,13 @@ internal class ConsoleDriverFacade<T> : IConsoleDriver, IConsoleDriverFacade
 
     private void CreateClipboard ()
     {
+        if (FakeDriver.FakeBehaviors.UseFakeClipboard)
+        {
+            Clipboard = new FakeDriver.FakeClipboard ();
+
+            return;
+        }
+
         PlatformID p = Environment.OSVersion.Platform;
 
         if (p == PlatformID.Win32NT || p == PlatformID.Win32S || p == PlatformID.Win32Windows)
@@ -88,7 +95,7 @@ internal class ConsoleDriverFacade<T> : IConsoleDriver, IConsoleDriverFacade
     ///     to.
     /// </summary>
     /// <value>The rectangle describing the of <see cref="Clip"/> region.</value>
-    public Region Clip
+    public Region? Clip
     {
         get => _outputBuffer.Clip;
         set => _outputBuffer.Clip = value;
@@ -114,7 +121,7 @@ internal class ConsoleDriverFacade<T> : IConsoleDriver, IConsoleDriverFacade
     ///     The contents of the application output. The driver outputs this buffer to the terminal.
     ///     <remarks>The format of the array is rows, columns. The first index is the row, the second index is the column.</remarks>
     /// </summary>
-    public Cell [,] Contents
+    public Cell [,]? Contents
     {
         get => _outputBuffer.Contents;
         set => _outputBuffer.Contents = value;
@@ -229,7 +236,7 @@ internal class ConsoleDriverFacade<T> : IConsoleDriver, IConsoleDriverFacade
     /// <summary>
     ///     Raised each time <see cref="ConsoleDriver.ClearContents"/> is called. For benchmarking.
     /// </summary>
-    public event EventHandler<EventArgs> ClearedContents;
+    public event EventHandler<EventArgs>? ClearedContents;
 
     /// <summary>
     ///     Fills the specified rectangle with the specified rune, using <see cref="ConsoleDriver.CurrentAttribute"/>
@@ -397,7 +404,7 @@ internal class ConsoleDriverFacade<T> : IConsoleDriver, IConsoleDriverFacade
     }
 
     /// <summary>Event fired when a key is pressed down. This is a precursor to <see cref="ConsoleDriver.KeyUp"/>.</summary>
-    public event EventHandler<Key> KeyDown;
+    public event EventHandler<Key>? KeyDown;
 
     /// <summary>Event fired when a key is released.</summary>
     /// <remarks>
@@ -405,10 +412,10 @@ internal class ConsoleDriverFacade<T> : IConsoleDriver, IConsoleDriverFacade
     ///     processing is
     ///     complete.
     /// </remarks>
-    public event EventHandler<Key> KeyUp;
+    public event EventHandler<Key>? KeyUp;
 
     /// <summary>Event fired when a mouse event occurs.</summary>
-    public event EventHandler<MouseEventArgs> MouseEvent;
+    public event EventHandler<MouseEventArgs>? MouseEvent;
 
     /// <summary>Simulates a key press.</summary>
     /// <param name="keyChar">The key character.</param>

Terminal.Gui/Drivers/V2/IConsoleDriverFacade.cs

@@ -1,4 +1,5 @@
-namespace Terminal.Gui.Drivers;
+#nullable enable
+namespace Terminal.Gui.Drivers;
 
 /// <summary>
 ///     Interface for v2 driver abstraction layer

Terminal.Gui/Drivers/V2/IOutputBuffer.cs

@@ -12,7 +12,7 @@ public interface IOutputBuffer
     /// <summary>
     ///     The contents of the application output. The driver outputs this buffer to the terminal when UpdateScreen is called.
     /// </summary>
-    Cell [,] Contents { get; set; }
+    Cell [,]? Contents { get; set; }
 
     /// <summary>
     ///     Gets or sets the clip rectangle that <see cref="AddRune(Rune)"/> and <see cref="AddStr(string)"/> are subject

Tests/TerminalGuiFluentTesting/FakeDriver/FakeApplicationFactory.cs

@@ -0,0 +1,45 @@
+#nullable enable
+using System.Drawing;
+using TerminalGuiFluentTesting;
+
+namespace Terminal.Gui.Drivers;
+
+#pragma warning disable CS1591
+public class FakeApplicationFactory
+{
+    /// <summary>
+    ///     Creates an initialized fake application which will be cleaned up when result object
+    ///     is disposed.
+    /// </summary>
+    /// <returns></returns>
+    public IDisposable SetupFakeApplication ()
+    {
+        var cts = new CancellationTokenSource ();
+        var fakeInput = new FakeNetInput (cts.Token);
+        FakeOutput output = new ();
+        output.Size = new (25, 25);
+
+        IApplication origApp = ApplicationImpl.Instance;
+
+        var sizeMonitor = new FakeSizeMonitor ();
+
+        var v2 = new ApplicationV2 (new FakeNetComponentFactory (fakeInput, output, sizeMonitor));
+
+        ApplicationImpl.ChangeInstance (v2);
+        v2.Init (null, "v2net");
+
+        ConsoleDriverFacade<ConsoleKeyInfo> d = (ConsoleDriverFacade<ConsoleKeyInfo>)Application.Driver!;
+
+        sizeMonitor.SizeChanging += (_, e) =>
+                                    {
+                                        if (e.Size != null)
+                                        {
+                                            Size s = e.Size.Value;
+                                            output.Size = s;
+                                            d.OutputBuffer.SetWindowSize (s.Width, s.Height);
+                                        }
+                                    };
+
+        return new FakeApplicationLifecycle (origApp, cts);
+    }
+}

Tests/TerminalGuiFluentTesting/FakeDriver/FakeApplicationLifecycle.cs

@@ -0,0 +1,16 @@
+#nullable enable
+namespace Terminal.Gui.Drivers;
+
+#pragma warning disable CS1591
+internal class FakeApplicationLifecycle (IApplication origApp, CancellationTokenSource hardStop) : IDisposable
+{
+    /// <inheritdoc/>
+    public void Dispose ()
+    {
+        hardStop.Cancel ();
+
+        Application.Top?.Dispose ();
+        Application.Shutdown ();
+        ApplicationImpl.ChangeInstance (origApp);
+    }
+}

Tests/TerminalGuiFluentTesting/FakeDriver/FakeDriverFactory.cs

@@ -0,0 +1,20 @@
+#nullable enable
+namespace Terminal.Gui.Drivers;
+
+#pragma warning disable CS1591
+public class FakeDriverFactory
+{
+    /// <summary>
+    ///     Creates a new instance of <see cref="FakeDriverV2"/> using default options
+    /// </summary>
+    /// <returns></returns>
+    public IFakeDriverV2 Create ()
+    {
+        return new FakeDriverV2 (
+                                 new (),
+                                 new (),
+                                 new (),
+                                 () => DateTime.Now,
+                                 new ());
+    }
+}

Tests/TerminalGuiFluentTesting/FakeDriver/FakeDriverV2.cs

@@ -0,0 +1,58 @@
+#nullable enable
+using System.Collections.Concurrent;
+using System.Drawing;
+using TerminalGuiFluentTesting;
+
+#pragma warning disable CS1591 // Missing XML comment for publicly visible type or member
+
+namespace Terminal.Gui.Drivers;
+
+/// <summary>
+///     Implementation of <see cref="IConsoleDriver"/> that uses fake input/output.
+///     This is a lightweight alternative to <see cref="GuiTestContext"/> (if you don't
+///     need the entire application main loop running).
+/// </summary>
+internal class FakeDriverV2 : ConsoleDriverFacade<ConsoleKeyInfo>, IFakeDriverV2
+{
+    internal FakeDriverV2 (
+        ConcurrentQueue<ConsoleKeyInfo> inputBuffer,
+        OutputBuffer outputBuffer,
+        FakeOutput fakeOutput,
+        Func<DateTime> datetimeFunc,
+        FakeSizeMonitor sizeMonitor
+    ) :
+        base (
+              new NetInputProcessor (inputBuffer),
+              outputBuffer,
+              fakeOutput,
+              new (new AnsiResponseParser (), datetimeFunc),
+              sizeMonitor)
+    {
+        FakeOutput fakeOutput1;
+        InputBuffer = inputBuffer;
+        SizeMonitor = sizeMonitor;
+        OutputBuffer = outputBuffer;
+        ConsoleOutput = fakeOutput1 = fakeOutput;
+
+        SizeChanged += (_, e) =>
+                       {
+                           if (e.Size != null)
+                           {
+                               Size s = e.Size.Value;
+                               fakeOutput1.Size = s;
+                               OutputBuffer.SetWindowSize (s.Width, s.Height);
+                           }
+                       };
+    }
+
+    public void SetBufferSize (int width, int height)
+    {
+        SizeMonitor.RaiseSizeChanging (new (width, height));
+        OutputBuffer.SetWindowSize (width, height);
+    }
+
+    public IConsoleOutput ConsoleOutput { get; }
+    public ConcurrentQueue<ConsoleKeyInfo> InputBuffer { get; }
+    public new OutputBuffer OutputBuffer { get; }
+    public FakeSizeMonitor SizeMonitor { get; }
+}

Tests/TerminalGuiFluentTesting/FakeDriver/FakeSizeMonitor.cs

@@ -0,0 +1,20 @@
+#nullable enable
+using System.Drawing;
+
+namespace Terminal.Gui.Drivers;
+
+#pragma warning disable CS1591
+public class FakeSizeMonitor : IWindowSizeMonitor
+{
+    /// <inheritdoc/>
+    public event EventHandler<SizeChangedEventArgs>? SizeChanging;
+
+    /// <inheritdoc/>
+    public bool Poll () { return false; }
+
+    /// <summary>
+    ///     Raises the <see cref="SizeChanging"/> event.
+    /// </summary>
+    /// <param name="newSize"></param>
+    public void RaiseSizeChanging (Size newSize) { SizeChanging?.Invoke (this, new (newSize)); }
+}

Tests/TerminalGuiFluentTesting/FakeDriver/IFakeDriverV2.cs

@@ -0,0 +1,8 @@
+#nullable enable
+namespace Terminal.Gui.Drivers;
+
+#pragma warning disable CS1591
+public interface IFakeDriverV2 : IConsoleDriver, IConsoleDriverFacade
+{
+    void SetBufferSize (int width, int height);
+}

Tests/TerminalGuiFluentTesting/FakeDriverV2.cs

@@ -1,159 +0,0 @@
-using System.Collections.Concurrent;
-using System.Drawing;
-using TerminalGuiFluentTesting;
-#pragma warning disable CS1591 // Missing XML comment for publicly visible type or member
-
-namespace Terminal.Gui.Drivers;
-
-public class FakeApplicationFactory
-{
-    /// <summary>
-    /// Creates an initialized fake application which will be cleaned up when result object
-    /// is disposed.
-    /// </summary>
-    /// <returns></returns>
-    public IDisposable SetupFakeApplication ()
-    {
-        var cts = new CancellationTokenSource ();
-        var fakeInput = new FakeNetInput (cts.Token);
-        FakeOutput output = new ();
-        output.Size = new (25, 25);
-
-
-        IApplication origApp = ApplicationImpl.Instance;
-
-        var sizeMonitor = new FakeSizeMonitor ();
-
-        var v2 = new ApplicationV2 (new FakeNetComponentFactory (fakeInput, output, sizeMonitor));
-
-        ApplicationImpl.ChangeInstance (v2);
-        v2.Init (null,"v2net");
-
-        var d = (ConsoleDriverFacade<ConsoleKeyInfo>)Application.Driver!;
-        sizeMonitor.SizeChanging += (_, e) =>
-                                           {
-                                               if (e.Size != null)
-                                               {
-                                                   var s = e.Size.Value;
-                                                   output.Size = s;
-                                                   d.OutputBuffer.SetWindowSize (s.Width, s.Height);
-                                               }
-                                           };
-
-        return new FakeApplicationLifecycle (origApp,cts);
-    }
-}
-
-class FakeApplicationLifecycle : IDisposable
-{
-    private readonly IApplication _origApp;
-    private readonly CancellationTokenSource _hardStop;
-
-    public FakeApplicationLifecycle (IApplication origApp, CancellationTokenSource hardStop)
-    {
-        _origApp = origApp;
-        _hardStop = hardStop;
-    }
-    /// <inheritdoc />
-    public void Dispose ()
-    {
-        _hardStop.Cancel();
-
-        Application.Top?.Dispose ();
-        Application.Shutdown ();
-        ApplicationImpl.ChangeInstance (_origApp);
-    }
-}
-
-public class FakeDriverFactory
-{
-    /// <summary>
-    /// Creates a new instance of <see cref="FakeDriverV2"/> using default options
-    /// </summary>
-    /// <returns></returns>
-    public IFakeDriverV2 Create ()
-    {
-        return new FakeDriverV2 (
-                                 new ConcurrentQueue<ConsoleKeyInfo> (),
-                                 new OutputBuffer (),
-                                 new FakeOutput (),
-                                 () => DateTime.Now,
-                                 new FakeSizeMonitor ());
-    }
-}
-
-public interface IFakeDriverV2 : IConsoleDriver, IConsoleDriverFacade
-{
-    void SetBufferSize (int width, int height);
-}
-
-/// <summary>
-/// Implementation of <see cref="IConsoleDriver"/> that uses fake input/output.
-/// This is a lightweight alternative to <see cref="GuiTestContext"/> (if you don't
-/// need the entire application main loop running).
-/// </summary>
-class FakeDriverV2 : ConsoleDriverFacade<ConsoleKeyInfo>, IFakeDriverV2
-{
-    public ConcurrentQueue<ConsoleKeyInfo> InputBuffer { get; }
-    public FakeSizeMonitor SizeMonitor { get; }
-    public new OutputBuffer OutputBuffer { get; }
-
-    public IConsoleOutput ConsoleOutput { get; }
-
-    private FakeOutput _fakeOutput;
-
-    internal FakeDriverV2 (
-        ConcurrentQueue<ConsoleKeyInfo> inputBuffer,
-        OutputBuffer outputBuffer,
-        FakeOutput fakeOutput,
-        Func<DateTime> datetimeFunc,
-        FakeSizeMonitor sizeMonitor) :
-        base (new NetInputProcessor (inputBuffer),
-             outputBuffer,
-             fakeOutput,
-             new (new AnsiResponseParser (), datetimeFunc),
-             sizeMonitor)
-    {
-        InputBuffer = inputBuffer;
-        SizeMonitor = sizeMonitor;
-        OutputBuffer = outputBuffer;
-        ConsoleOutput = _fakeOutput = fakeOutput;
-        SizeChanged += (_, e) =>
-                       {
-                           if (e.Size != null)
-                           {
-                               var s = e.Size.Value;
-                               _fakeOutput.Size = s;
-                               OutputBuffer.SetWindowSize (s.Width,s.Height);
-                           }
-                       };
-
-    }
-
-    public void SetBufferSize (int width, int height)
-    {
-        SizeMonitor.RaiseSizeChanging (new Size (width,height));
-        OutputBuffer.SetWindowSize (width,height);
-    }
-}
-
-public class FakeSizeMonitor : IWindowSizeMonitor
-{
-    /// <inheritdoc />
-    public event EventHandler<SizeChangedEventArgs>? SizeChanging;
-
-    /// <inheritdoc />
-    public bool Poll ()
-    {
-        return false;
-    }
-
-    /// <summary>
-    /// Raises the <see cref="SizeChanging"/> event.
-    /// </summary>
-    /// <param name="newSize"></param>
-    public void RaiseSizeChanging (Size newSize)
-    {
-        SizeChanging?.Invoke (this,new (newSize));
-    }
-}

Tests/TerminalGuiFluentTesting/FakeOutput.cs

@@ -4,7 +4,7 @@ namespace TerminalGuiFluentTesting;
 
 internal class FakeOutput : IConsoleOutput
 {
-    public IOutputBuffer LastBuffer { get; set; }
+    public IOutputBuffer? LastBuffer { get; set; }
     public Size Size { get; set; }
 
     /// <inheritdoc/>