Fixes #3985. Remove unix driver; augment ansi driver to support configurable size detection

Terminal.Gui/App/ApplicationImpl.Driver.cs

@@ -83,11 +83,6 @@ private void CreateDriver (string? driverName)
 
                     break;
 
-                case DriverRegistry.Names.UNIX:
-                    Coordinator = CreateSubcomponents (() => new UnixComponentFactory ());
-
-                    break;
-
                 case DriverRegistry.Names.ANSI:
                     Coordinator = CreateSubcomponents (() => new AnsiComponentFactory ());
 

Terminal.Gui/Configuration/SourceGenerationContext.cs

@@ -45,6 +45,7 @@ namespace Terminal.Gui.Configuration;
 [JsonSerializable (typeof (Dictionary<string, Scheme>))]
 
 [JsonSerializable (typeof (TraceCategory))]
+[JsonSerializable (typeof (SizeDetectionMode))]
 
 internal partial class SourceGenerationContext : JsonSerializerContext
 { }

Terminal.Gui/Drivers/AnsiDriver/AnsiComponentFactory.cs

@@ -24,34 +24,41 @@ public class AnsiComponentFactory : ComponentFactoryImpl<char>
 
     private readonly AnsiInput? _input;
     private readonly IOutput? _output;
-    private AnsiSizeMonitor? _createdSizeMonitor;
+    private readonly ISizeMonitor? _injectedSizeMonitor;
 
     /// <summary>
     ///     Creates a new ANSIComponentFactory with optional output capture.
     /// </summary>
     /// <param name="input"></param>
     /// <param name="output">Optional fake output to capture what would be written to console.</param>
-    /// <param name="sizeMonitor">Optional size monitor (if null, will create ANSISizeMonitor)</param>
+    /// <param name="sizeMonitor">Optional size monitor override (used in tests; if <see langword="null"/>, the monitor is chosen based on <see cref="Driver.SizeDetection"/>).</param>
     public AnsiComponentFactory (AnsiInput? input = null, IOutput? output = null, ISizeMonitor? sizeMonitor = null)
     {
         _input = input;
         _output = output;
-        _createdSizeMonitor = sizeMonitor as AnsiSizeMonitor;
+        _injectedSizeMonitor = sizeMonitor;
     }
 
 
     /// <inheritdoc/>
     public override ISizeMonitor CreateSizeMonitor (IOutput consoleOutput, IOutputBuffer outputBuffer)
     {
-        if (consoleOutput is AnsiOutput output)
+        // Return injected monitor (e.g. from test harness) if one was provided.
+        if (_injectedSizeMonitor is { })
         {
-            // Create ANSISizeMonitor - the ANSI request callback will be set up
-            // by MainLoopCoordinator after the driver is fully constructed
-            _createdSizeMonitor = new (output, queueAnsiRequest: null);
-            return _createdSizeMonitor;
+            return _injectedSizeMonitor;
         }
 
-        // Fallback for other output types
+        // When AnsiQuery mode is requested, use the ANSI escape-sequence monitor.
+        if (Driver.SizeDetection == SizeDetectionMode.AnsiQuery
+            && consoleOutput is AnsiOutput ansiOutput)
+        {
+            // The ANSI request callback will be set up by MainLoopCoordinator
+            // after the driver is fully constructed.
+            return new AnsiSizeMonitor (ansiOutput, queueAnsiRequest: null);
+        }
+
+        // Default: synchronous polling via ioctl / Console API.
         return new SizeMonitorImpl (consoleOutput);
     }
 

Terminal.Gui/Drivers/AnsiHandling/AnsiKeyConverter.cs

@@ -10,8 +10,8 @@ namespace Terminal.Gui.Drivers;
 ///         for escape sequence parsing.
 ///     </para>
 ///     <list type="bullet">
-///         <item><see cref="UnixInputProcessor"/> - Raw terminal input on Unix/Linux/macOS</item>
-///         <item><see cref="AnsiInputProcessor"/> - ANSI-based test driver</item>
+///         
+///         <item><see cref="AnsiInputProcessor"/> - ANSI-based driver for Unix/Linux/macOS and testing</item>
 ///     </list>
 ///     <para>
 ///         The conversion uses <see cref="ConsoleKeyInfo"/> as an intermediary format,

Terminal.Gui/Drivers/Driver.cs

@@ -29,6 +29,20 @@ public static bool Force16Colors
     /// <summary>Raised when <see cref="Force16Colors"/> changes.</summary>
     public static event EventHandler<ValueChangedEventArgs<bool>>? Force16ColorsChanged;
 
+    // NOTE: SizeDetection is a configuration property (Driver.SizeDetection).
+    // It controls which strategy the ANSI driver uses to determine the terminal's size.
+    /// <summary>
+    ///     Controls how the ANSI driver detects the terminal's window size.
+    ///     Defaults to <see cref="SizeDetectionMode.Polling"/>, which uses a synchronous
+    ///     native syscall (<c>ioctl</c> on Unix, Console API on Windows) for immediate,
+    ///     reliable size information.  Set to <see cref="SizeDetectionMode.AnsiQuery"/>
+    ///     to use pure-ANSI escape-sequence queries instead (useful when the native API
+    ///     does not reflect the remote terminal size, e.g. over an SSH tunnel).
+    /// </summary>
+    /// <seealso cref="SizeDetectionMode"/>
+    [ConfigurationProperty (Scope = typeof (SettingsScope))]
+    public static SizeDetectionMode SizeDetection { get; set; } = SizeDetectionMode.Polling;
+
     /// <summary>
     ///     Determines whether the process is attached to a real terminal (i.e. stdin/stdout
     ///     are connected to a console device rather than redirected or running inside a test harness). Set the environment

Terminal.Gui/Drivers/DriverRegistry.cs

@@ -17,9 +17,6 @@ public static class Names
         /// <summary>.NET System.Console cross-platform driver name.</summary>
         public const string DOTNET = "dotnet";
 
-        /// <summary>Unix/Linux/macOS terminal driver name.</summary>
-        public const string UNIX = "unix";
-
         /// <summary>Pure ANSI escape sequence cross-platform driver name.</summary>
         public const string ANSI = "ansi";
     }
@@ -63,15 +60,6 @@ static DriverRegistry ()
                        () => new NetComponentFactory ()
                       ));
 
-        Register (
-                  new (
-                       Names.UNIX,
-                       "Unix/Linux Terminal Driver",
-                       "Optimized Unix/Linux/macOS driver with raw terminal mode",
-                       [PlatformID.Unix, PlatformID.MacOSX],
-                       () => new UnixComponentFactory ()
-                      ));
-
         Register (
                   new (
                        Names.ANSI,
@@ -145,7 +133,7 @@ public static DriverDescriptor GetDefaultDriver ()
 
         if (p == PlatformID.Unix)
         {
-            return _registry [Names.UNIX];
+            return _registry [Names.ANSI];
         }
 
         // Fallback to dotnet

Terminal.Gui/Drivers/Input/IInput.cs

@@ -42,7 +42,6 @@ namespace Terminal.Gui.Drivers;
 ///     <list type="bullet">
 ///         <item><see cref="WindowsInput"/> - Uses Windows Console API (<c>ReadConsoleInput</c>)</item>
 ///         <item><see cref="NetInput"/> - Uses .NET <see cref="System.Console"/> API</item>
-///         <item><see cref="UnixInput"/> - Uses Unix terminal APIs</item>
 ///         <item><see cref="AnsiInput"/> - For testing, implements <see cref="ITestableInput{TInputRecord}"/></item>
 ///     </list>
 ///     <para>

Terminal.Gui/Drivers/SizeDetectionMode.cs

@@ -0,0 +1,21 @@
+namespace Terminal.Gui.Drivers;
+
+/// <summary>
+///     Controls how the ANSI driver detects the terminal's window size.
+/// </summary>
+public enum SizeDetectionMode
+{
+    /// <summary>
+    ///     Uses <c>ioctl(TIOCGWINSZ)</c> on Unix/macOS or the Console API on Windows.
+    ///     Synchronous, immediate, and reliable. This is the default.
+    /// </summary>
+    Polling,
+
+    /// <summary>
+    ///     Sends a <c>CSI 18t</c> ANSI escape-sequence query and parses the
+    ///     <c>ESC [ 8 ; height ; width t</c> response.  Works over SSH or any
+    ///     ANSI-compatible terminal but is asynchronous and throttled to one
+    ///     query per 500 ms.
+    /// </summary>
+    AnsiQuery
+}