Fixes #3771. TextView doesn't consider no-printable rune in draw and cursor position.

Terminal.Gui/Drawing/Cell.cs

@@ -4,19 +4,18 @@
 ///     Represents a single row/column in a Terminal.Gui rendering surface (e.g. <see cref="LineCanvas"/> and
 ///     <see cref="ConsoleDriver"/>).
 /// </summary>
-public record struct Cell ()
+public record struct Cell (Attribute? Attribute = null, bool IsDirty = false, Rune Rune = default)
 {
-
     /// <summary>The attributes to use when drawing the Glyph.</summary>
-    public Attribute? Attribute { get; set; } = null;
+    public Attribute? Attribute { get; set; } = Attribute;
 
     /// <summary>
     ///     Gets or sets a value indicating whether this <see cref="T:Terminal.Gui.Cell"/> has been modified since the
     ///     last time it was drawn.
     /// </summary>
-    public bool IsDirty { get; set; } = false;
+    public bool IsDirty { get; set; } = IsDirty;
 
-    private Rune _rune = default;
+    private Rune _rune = Rune;
 
     /// <summary>The character to display. If <see cref="Rune"/> is <see langword="null"/>, then <see cref="Rune"/> is ignored.</summary>
     public Rune Rune
@@ -29,6 +28,8 @@ public Rune Rune
         }
     }
 
+    private List<Rune> _combiningMarks;
+
     /// <summary>
     ///     The combining marks for <see cref="Rune"/> that when combined makes this Cell a combining sequence. If
     ///     <see cref="CombiningMarks"/> empty, then <see cref="CombiningMarks"/> is ignored.
@@ -37,8 +38,132 @@ public Rune Rune
     ///     Only valid in the rare case where <see cref="Rune"/> is a combining sequence that could not be normalized to a
     ///     single Rune.
     /// </remarks>
-    internal List<Rune> CombiningMarks { get; } = new ();
+    internal List<Rune> CombiningMarks
+    {
+        get => _combiningMarks ?? [];
+        private set => _combiningMarks = value ?? [];
+    }
 
     /// <inheritdoc/>
     public override string ToString () { return $"[{Rune}, {Attribute}]"; }
+
+    /// <summary>Converts the string into a <see cref="List{Cell}"/>.</summary>
+    /// <param name="str">The string to convert.</param>
+    /// <param name="attribute">The <see cref="Gui.ColorScheme"/> to use.</param>
+    /// <returns></returns>
+    public static List<Cell> ToCellList (string str, Attribute? attribute = null)
+    {
+        List<Cell> cells = new ();
+
+        foreach (Rune rune in str.EnumerateRunes ())
+        {
+            cells.Add (new () { Rune = rune, Attribute = attribute });
+        }
+
+        return cells;
+    }
+
+    /// <summary>
+    ///     Splits a string into a List that will contain a <see cref="List{Cell}"/> for each line.
+    /// </summary>
+    /// <param name="content">The string content.</param>
+    /// <param name="attribute">The color scheme.</param>
+    /// <returns>A <see cref="List{Cell}"/> for each line.</returns>
+    public static List<List<Cell>> StringToLinesOfCells (string content, Attribute? attribute = null)
+    {
+        List<Cell> cells = content.EnumerateRunes ()
+                                      .Select (x => new Cell { Rune = x, Attribute = attribute })
+                                      .ToList ();
+
+        return SplitNewLines (cells);
+    }
+
+    /// <summary>Converts a <see cref="Cell"/> generic collection into a string.</summary>
+    /// <param name="cells">The enumerable cell to convert.</param>
+    /// <returns></returns>
+    public static string ToString (IEnumerable<Cell> cells)
+    {
+        var str = string.Empty;
+
+        foreach (Cell cell in cells)
+        {
+            str += cell.Rune.ToString ();
+        }
+
+        return str;
+    }
+
+    // Turns the string into cells, this does not split the contents on a newline if it is present.
+
+    internal static List<Cell> StringToCells (string str, Attribute? attribute = null)
+    {
+        List<Cell> cells = [];
+
+        foreach (Rune rune in str.ToRunes ())
+        {
+            cells.Add (new () { Rune = rune, Attribute = attribute });
+        }
+
+        return cells;
+    }
+
+    internal static List<Cell> ToCells (IEnumerable<Rune> runes, Attribute? attribute = null)
+    {
+        List<Cell> cells = new ();
+
+        foreach (Rune rune in runes)
+        {
+            cells.Add (new () { Rune = rune, Attribute = attribute });
+        }
+
+        return cells;
+    }
+
+    private static List<List<Cell>> SplitNewLines (List<Cell> cells)
+    {
+        List<List<Cell>> lines = [];
+        int start = 0, i = 0;
+        var hasCR = false;
+
+        // ASCII code 13 = Carriage Return.
+        // ASCII code 10 = Line Feed.
+        for (; i < cells.Count; i++)
+        {
+            if (cells [i].Rune.Value == 13)
+            {
+                hasCR = true;
+
+                continue;
+            }
+
+            if (cells [i].Rune.Value == 10)
+            {
+                if (i - start > 0)
+                {
+                    lines.Add (cells.GetRange (start, hasCR ? i - 1 - start : i - start));
+                }
+                else
+                {
+                    lines.Add (StringToCells (string.Empty));
+                }
+
+                start = i + 1;
+                hasCR = false;
+            }
+        }
+
+        if (i - start >= 0)
+        {
+            lines.Add (cells.GetRange (start, i - start));
+        }
+
+        return lines;
+    }
+
+    /// <summary>
+    ///     Splits a rune cell list into a List that will contain a <see cref="List{Cell}"/> for each line.
+    /// </summary>
+    /// <param name="cells">The cells list.</param>
+    /// <returns></returns>
+    public static List<List<Cell>> ToCells (List<Cell> cells) { return SplitNewLines (cells); }
 }

Terminal.Gui/Views/RuneCellEventArgs.cs → Terminal.Gui/Drawing/CellEventArgs.cs

@@ -1,27 +1,27 @@
 namespace Terminal.Gui;
 
-/// <summary>Args for events that relate to a specific <see cref="RuneCell"/>.</summary>
-public class RuneCellEventArgs
+/// <summary>Args for events that relate to a specific <see cref="Cell"/>.</summary>
+public class CellEventArgs
 {
-    /// <summary>Creates a new instance of the <see cref="RuneCellEventArgs"/> class.</summary>
+    /// <summary>Creates a new instance of the <see cref="CellEventArgs"/> class.</summary>
     /// <param name="line">The line.</param>
     /// <param name="col">The col index.</param>
     /// <param name="unwrappedPosition">The unwrapped row and col index.</param>
-    public RuneCellEventArgs (List<RuneCell> line, int col, (int Row, int Col) unwrappedPosition)
+    public CellEventArgs (List<Cell> line, int col, (int Row, int Col) unwrappedPosition)
     {
         Line = line;
         Col = col;
         UnwrappedPosition = unwrappedPosition;
     }
 
-    /// <summary>The index of the RuneCell in the line.</summary>
+    /// <summary>The index of the Cell in the line.</summary>
     public int Col { get; }
 
-    /// <summary>The list of runes the RuneCell is part of.</summary>
-    public List<RuneCell> Line { get; }
+    /// <summary>The list of runes the Cell is part of.</summary>
+    public List<Cell> Line { get; }
 
     /// <summary>
-    ///     The unwrapped row and column index into the text containing the RuneCell. Unwrapped means the text without
+    ///     The unwrapped row and column index into the text containing the Cell. Unwrapped means the text without
     ///     word wrapping or other visual formatting having been applied.
     /// </summary>
     public (int Row, int Col) UnwrappedPosition { get; }

Terminal.Gui/Drawing/LineCanvas.cs

@@ -138,7 +138,7 @@ public void AddLine (
         int length,
         Orientation orientation,
         LineStyle style,
-        Attribute? attribute = default
+        Attribute? attribute = null
     )
     {
         _cachedViewport = Rectangle.Empty;

Terminal.Gui/Drawing/StraightLine.cs

@@ -16,7 +16,7 @@ public StraightLine (
         int length,
         Orientation orientation,
         LineStyle style,
-        Attribute? attribute = default
+        Attribute? attribute = null
     )
     {
         Start = start;

Terminal.Gui/Text/Autocomplete/AutocompleteContext.cs

@@ -7,7 +7,7 @@ namespace Terminal.Gui;
 public class AutocompleteContext
 {
     /// <summary>Creates a new instance of the <see cref="AutocompleteContext"/> class</summary>
-    public AutocompleteContext (List<RuneCell> currentLine, int cursorPosition, bool canceled = false)
+    public AutocompleteContext (List<Cell> currentLine, int cursorPosition, bool canceled = false)
     {
         CurrentLine = currentLine;
         CursorPosition = cursorPosition;
@@ -18,7 +18,7 @@ public AutocompleteContext (List<RuneCell> currentLine, int cursorPosition, bool
     public bool Canceled { get; set; }
 
     /// <summary>The text on the current line.</summary>
-    public List<RuneCell> CurrentLine { get; set; }
+    public List<Cell> CurrentLine { get; set; }
 
     /// <summary>The position of the input cursor within the <see cref="CurrentLine"/>.</summary>
     public int CursorPosition { get; set; }

Terminal.Gui/Views/AutocompleteFilepathContext.cs

@@ -6,7 +6,7 @@ namespace Terminal.Gui;
 internal class AutocompleteFilepathContext : AutocompleteContext
 {
     public AutocompleteFilepathContext (string currentLine, int cursorPosition, FileDialogState state)
-        : base (TextModel.ToRuneCellList (currentLine), cursorPosition)
+        : base (Cell.ToCellList (currentLine), cursorPosition)
     {
         State = state;
     }
@@ -30,7 +30,7 @@ public IEnumerable<Suggestion> GenerateSuggestions (AutocompleteContext context)
             return Enumerable.Empty<Suggestion> ();
         }
 
-        var path = TextModel.ToString (context.CurrentLine);
+        var path = Cell.ToString (context.CurrentLine);
         int last = path.LastIndexOfAny (FileDialog.Separators);
 
         if (string.IsNullOrWhiteSpace (path) || !Path.IsPathRooted (path))

Terminal.Gui/Views/HistoryTextItemEventArgs.cs

@@ -9,11 +9,11 @@ public class HistoryTextItemEventArgs : EventArgs
         public Point CursorPosition;
         public Point FinalCursorPosition;
         public bool IsUndoing;
-        public List<List<RuneCell>> Lines;
+        public List<List<Cell>> Lines;
         public LineStatus LineStatus;
         public HistoryTextItemEventArgs RemovedOnAdded;
 
-        public HistoryTextItemEventArgs (List<List<RuneCell>> lines, Point curPos, LineStatus linesStatus)
+        public HistoryTextItemEventArgs (List<List<Cell>> lines, Point curPos, LineStatus linesStatus)
         {
             Lines = lines;
             CursorPosition = curPos;
@@ -22,7 +22,7 @@ public HistoryTextItemEventArgs (List<List<RuneCell>> lines, Point curPos, LineS
 
         public HistoryTextItemEventArgs (HistoryTextItemEventArgs historyTextItem)
         {
-            Lines = new List<List<RuneCell>> (historyTextItem.Lines);
+            Lines = new List<List<Cell>> (historyTextItem.Lines);
             CursorPosition = new Point (historyTextItem.CursorPosition.X, historyTextItem.CursorPosition.Y);
             LineStatus = historyTextItem.LineStatus;
         }

Terminal.Gui/Views/TextField.cs

@@ -546,12 +546,12 @@ public string SelectedText
             if (!Secret && !_historyText.IsFromHistory)
             {
                 _historyText.Add (
-                                  new List<List<RuneCell>> { TextModel.ToRuneCellList (oldText) },
+                                  new List<List<Cell>> { Cell.ToCellList (oldText) },
                                   new Point (_cursorPosition, 0)
                                  );
 
                 _historyText.Add (
-                                  new List<List<RuneCell>> { TextModel.ToRuneCells (_text) },
+                                  new List<List<Cell>> { Cell.ToCells (_text) },
                                   new Point (_cursorPosition, 0),
                                   HistoryText.LineStatus.Replaced
                                  );
@@ -648,7 +648,7 @@ public virtual void DeleteCharLeft (bool usePreTextChangedCursorPos)
         }
 
         _historyText.Add (
-                          new List<List<RuneCell>> { TextModel.ToRuneCells (_text) },
+                          new List<List<Cell>> { Cell.ToCells (_text) },
                           new Point (_cursorPosition, 0)
                          );
 
@@ -702,7 +702,7 @@ public virtual void DeleteCharRight ()
         }
 
         _historyText.Add (
-                          new List<List<RuneCell>> { TextModel.ToRuneCells (_text) },
+                          new List<List<Cell>> { Cell.ToCells (_text) },
                           new Point (_cursorPosition, 0)
                          );
 
@@ -952,7 +952,7 @@ public override void OnDrawContent (Rectangle viewport)
 
         int p = ScrollOffset;
         var col = 0;
-        int width = Frame.Width + OffSetBackground ();
+        int width = Viewport.Width + OffSetBackground ();
         int tcount = _text.Count;
         Attribute roc = GetReadOnlyColor ();
 
@@ -1140,10 +1140,10 @@ public virtual void Paste ()
             }
 
             int cols = _text [idx].GetColumns ();
-            TextModel.SetCol (ref col, Frame.Width - 1, cols);
+            TextModel.SetCol (ref col, Viewport.Width - 1, cols);
         }
 
-        int pos = _cursorPosition - ScrollOffset + Math.Min (Frame.X, 0);
+        int pos = _cursorPosition - ScrollOffset + Math.Min (Viewport.X, 0);
         Move (pos, 0);
         return new Point (pos, 0);
     }
@@ -1225,16 +1225,16 @@ private void Adjust ()
             ScrollOffset = _cursorPosition;
             need = true;
         }
-        else if (Frame.Width > 0
-                 && (ScrollOffset + _cursorPosition - (Frame.Width + offB) == 0
-                     || TextModel.DisplaySize (_text, ScrollOffset, _cursorPosition).size >= Frame.Width + offB))
+        else if (Viewport.Width > 0
+                 && (ScrollOffset + _cursorPosition - (Viewport.Width + offB) == 0
+                     || TextModel.DisplaySize (_text, ScrollOffset, _cursorPosition).size >= Viewport.Width + offB))
         {
             ScrollOffset = Math.Max (
                                      TextModel.CalculateLeftColumn (
                                                                     _text,
                                                                     ScrollOffset,
                                                                     _cursorPosition,
-                                                                    Frame.Width + offB
+                                                                    Viewport.Width + offB
                                                                    ),
                                      0
                                     );
@@ -1342,7 +1342,7 @@ private List<Rune> DeleteSelectedText ()
 
     private void GenerateSuggestions ()
     {
-        List<RuneCell> currentLine = TextModel.ToRuneCellList (Text);
+        List<Cell> currentLine = Cell.ToCellList (Text);
         int cursorPosition = Math.Min (CursorPosition, currentLine.Count);
 
         Autocomplete.Context = new AutocompleteContext (
@@ -1390,15 +1390,15 @@ private void HistoryText_ChangeText (object sender, HistoryText.HistoryTextItemE
             return;
         }
 
-        Text = TextModel.ToString (obj?.Lines [obj.CursorPosition.Y]);
+        Text = Cell.ToString (obj?.Lines [obj.CursorPosition.Y]);
         CursorPosition = obj.CursorPosition.X;
         Adjust ();
     }
 
     private void InsertText (Key a, bool usePreTextChangedCursorPos)
     {
         _historyText.Add (
-                          new List<List<RuneCell>> { TextModel.ToRuneCells (_text) },
+                          new List<List<Cell>> { Cell.ToCells (_text) },
                           new Point (_cursorPosition, 0)
                          );