Merge branch 'master' of tig:migueldeicaza/gui.cs

FSharpExample/Program.fs

@@ -140,7 +140,7 @@ type Demo() = class end
         container.Add (login, loginText, password, passText,
             new FrameView (new Rect (3, 10, 25, 6), ustr "Options",
                 [|new CheckBox (1, 0, ustr "Remember me");
-                new RadioGroup (1, 2, [|"_Personal"; "_Company"|])|]
+                new RadioGroup (1, 2, [|ustr "_Personal"; ustr "_Company"|])|]
                 ),
             new ListView (new Rect(59, 6, 16, 4),
                     [|"First row";
@@ -434,8 +434,7 @@ type Demo() = class end
             new StatusItem(Key.F2, ustr "~F2~ Load", Action(Load));
             new StatusItem(Key.F3, ustr "~F3~ Save", Action(Save));
             new StatusItem(Key.ControlX, ustr "~^X~ Quit", fun () -> if (Quit ()) then top.Running <- false)
-            |],
-            Parent = null
+            |]
             )
         win.Add (drag, dragText)
         let mutable bottom = new Label(ustr "This should go on the bottom of the same top-level!")

Terminal.Gui/ConsoleDrivers/CursesDriver/CursesDriver.cs

@@ -39,14 +39,14 @@ namespace Terminal.Gui {
 		}
 
 		static bool sync = false;
-		public override void AddRune (Rune rune)
+		public override void AddRune (Rune rune) 
 		{
 			if (Clip.Contains (ccol, crow)) {
 				if (needMove) {
 					Curses.move (crow, ccol);
 					needMove = false;
 				}
-				Curses.addch ((int)(uint)rune);
+				Curses.addch ((int)(uint)MakePrintable(rune));
 			} else
 				needMove = true;
 			if (sync)

Terminal.Gui/ConsoleDrivers/FakeDriver/FakeDriver.cs

@@ -90,6 +90,7 @@ namespace Terminal.Gui {
 		/// <param name="rune"></param>
 		public override void AddRune (Rune rune)
 		{
+			rune = MakePrintable (rune);
 			if (Clip.Contains (ccol, crow)) {
 				if (needMove) {
 					//MockConsole.CursorLeft = ccol;

Terminal.Gui/ConsoleDrivers/NetDriver.cs

@@ -70,6 +70,7 @@ namespace Terminal.Gui {
 
 		public override void AddRune (Rune rune)
 		{
+			rune = MakePrintable (rune);
 			if (Clip.Contains (ccol, crow)) {
 				if (needMove) {
 					//Console.CursorLeft = ccol;

Terminal.Gui/ConsoleDrivers/WindowsDriver.cs

@@ -1182,6 +1182,7 @@ namespace Terminal.Gui {
 
 		public override void AddRune (Rune rune)
 		{
+			rune = MakePrintable (rune);
 			var position = crow * Cols + ccol;
 
 			if (Clip.Contains (ccol, crow)) {

Terminal.Gui/Core/ConsoleDriver.cs

@@ -1,4 +1,4 @@
-//
+//
 // ConsoleDriver.cs: Definition for the Console Driver API
 //
 // Authors:
@@ -558,6 +558,28 @@ namespace Terminal.Gui {
 		/// <param name="rune">Rune to add.</param>
 		public abstract void AddRune (Rune rune);
 		/// <summary>
+		/// Ensures a Rune is not a control character and can be displayed by translating characters below 0x20
+		/// to equivalent, printable, Unicode chars.
+		/// </summary>
+		/// <param name="c">Rune to translate</param>
+		/// <returns></returns>
+		public static Rune MakePrintable (Rune c)
+		{
+			if (c <= 0x1F) {
+				// ASCII (C0) control characters. 
+				return new Rune (c + 0x2400);
+			} else if (c >= 0x80 && c <= 0x9F) {
+				// C1 control characters (https://www.aivosto.com/articles/control-characters.html#c1)
+				return new Rune (0x25a1); // U+25A1, WHITE SQUARE, □: 
+			} else if (Rune.ColumnWidth (c) > 1) {
+				// BUGBUG: Until we figure out how to fix #41. Note this still doesn't help when 
+				// an Emoji or other char doesn't represent it's width correctly
+				return new Rune (0x25a1); // U+25A1, WHITE SQUARE, □: 
+			} else {
+				return c;
+			}
+		}
+		/// <summary>
 		/// Adds the specified
 		/// </summary>
 		/// <param name="str">String.</param>

Terminal.Gui/Core/PosDim.cs

@@ -279,7 +279,7 @@ namespace Terminal.Gui {
 			}
 			internal override int Anchor (int width)
 			{
-				switch(side) {
+				switch (side) {
 				case 0: return Target.Frame.X;
 				case 1: return Target.Frame.Y;
 				case 2: return Target.Frame.Right;
@@ -292,7 +292,7 @@ namespace Terminal.Gui {
 			public override string ToString ()
 			{
 				string tside;
-				switch(side) {
+				switch (side) {
 				case 0: tside = "x"; break;
 				case 1: tside = "y"; break;
 				case 2: tside = "right"; break;
@@ -308,42 +308,42 @@ namespace Terminal.Gui {
 		/// </summary>
 		/// <returns>The <see cref="Pos"/> that depends on the other view.</returns>
 		/// <param name="view">The <see cref="View"/>  that will be tracked.</param>
-		public static Pos Left (View view) => new PosView (view, 0);
+		public static Pos Left (View view) => new PosCombine (true, new PosView (view, 0), new Pos.PosAbsolute (0));
 
 		/// <summary>
 		/// Returns a <see cref="Pos"/> object tracks the Left (X) position of the specified <see cref="View"/>.
 		/// </summary>
 		/// <returns>The <see cref="Pos"/> that depends on the other view.</returns>
 		/// <param name="view">The <see cref="View"/>  that will be tracked.</param>
-		public static Pos X (View view) => new PosView (view, 0);
+		public static Pos X (View view) => new PosCombine (true, new PosView (view, 0), new Pos.PosAbsolute (0));
 
 		/// <summary>
 		/// Returns a <see cref="Pos"/> object tracks the Top (Y) position of the specified <see cref="View"/>.
 		/// </summary>
 		/// <returns>The <see cref="Pos"/> that depends on the other view.</returns>
 		/// <param name="view">The <see cref="View"/>  that will be tracked.</param>
-		public static Pos Top (View view) => new PosView (view, 1);
+		public static Pos Top (View view) => new PosCombine (true, new PosView (view, 1), new Pos.PosAbsolute (0));
 
 		/// <summary>
 		/// Returns a <see cref="Pos"/> object tracks the Top (Y) position of the specified <see cref="View"/>.
 		/// </summary>
 		/// <returns>The <see cref="Pos"/> that depends on the other view.</returns>
 		/// <param name="view">The <see cref="View"/>  that will be tracked.</param>
-		public static Pos Y (View view) => new PosView (view, 1);
+		public static Pos Y (View view) => new PosCombine (true, new PosView (view, 1), new Pos.PosAbsolute (0));
 
 		/// <summary>
 		/// Returns a <see cref="Pos"/> object tracks the Right (X+Width) coordinate of the specified <see cref="View"/>.
 		/// </summary>
 		/// <returns>The <see cref="Pos"/> that depends on the other view.</returns>
 		/// <param name="view">The <see cref="View"/>  that will be tracked.</param>
-		public static Pos Right (View view) => new PosView (view, 2);
+		public static Pos Right (View view) => new PosCombine (true, new PosView (view, 2), new Pos.PosAbsolute (0));
 
 		/// <summary>
 		/// Returns a <see cref="Pos"/> object tracks the Bottom (Y+Height) coordinate of the specified <see cref="View"/> 
 		/// </summary>
 		/// <returns>The <see cref="Pos"/> that depends on the other view.</returns>
 		/// <param name="view">The <see cref="View"/>  that will be tracked.</param>
-		public static Pos Bottom (View view) => new PosView (view, 3);
+		public static Pos Bottom (View view) => new PosCombine (true, new PosView (view, 3), new Pos.PosAbsolute (0));
 	}
 
 	/// <summary>
@@ -546,7 +546,7 @@ namespace Terminal.Gui {
 			public override string ToString ()
 			{
 				string tside;
-				switch(side) {
+				switch (side) {
 				case 0: tside = "Height"; break;
 				case 1: tside = "Width"; break;
 				default: tside = "unknown"; break;
@@ -556,7 +556,7 @@ namespace Terminal.Gui {
 
 			internal override int Anchor (int width)
 			{
-				switch(side) {
+				switch (side) {
 				case 0: return Target.Frame.Height;
 				case 1: return Target.Frame.Width;
 				default:

Terminal.Gui/Views/Button.cs

@@ -62,7 +62,7 @@ namespace Terminal.Gui {
 		///   The width of the <see cref="Button"/> is computed based on the
 		///   text length. The height will always be 1.
 		/// </remarks>
-		public Button () : this (string.Empty) { }
+		public Button () : this (text: string.Empty, is_default: false) { }
 
 		/// <summary>
 		///   Initializes a new instance of <see cref="Button"/> using <see cref="LayoutStyle.Computed"/> layout.
@@ -78,11 +78,7 @@ namespace Terminal.Gui {
 		/// </param>
 		public Button (ustring text, bool is_default = false) : base ()
 		{
-			CanFocus = true;
-			Text = text ?? string.Empty;
-			this.IsDefault = is_default;
-			int w = SetWidthHeight (text, is_default);
-			Frame = new Rect (Frame.Location, new Size (w, 1));
+			Init (text, is_default);
 		}
 
 		/// <summary>
@@ -114,9 +110,26 @@ namespace Terminal.Gui {
 		public Button (int x, int y, ustring text, bool is_default)
 		    : base (new Rect (x, y, text.Length + 4 + (is_default ? 2 : 0), 1))
 		{
+			Init (text, is_default);
+		}
+
+		Rune _leftBracket;
+		Rune _rightBracket;
+		Rune _leftDefault;
+		Rune _rightDefault;
+
+		void Init (ustring text, bool is_default)
+		{
+			_leftBracket = new Rune (Driver != null ? Driver.LeftBracket : '[');
+			_rightBracket = new Rune (Driver != null ? Driver.RightBracket : ']');
+			_leftDefault = new Rune (Driver != null ? Driver.LeftDefaultIndicator : '<');
+			_rightDefault = new Rune (Driver != null ? Driver.RightDefaultIndicator : '>');
+
 			CanFocus = true;
 			Text = text ?? string.Empty;
 			this.IsDefault = is_default;
+			int w = SetWidthHeight (text, is_default);
+			Frame = new Rect (Frame.Location, new Size (w, 1));
 		}
 
 		int SetWidthHeight (ustring text, bool is_default)
@@ -154,11 +167,6 @@ namespace Terminal.Gui {
 			}
 		}
 
-		Rune _leftBracket = new Rune (Driver != null ? Driver.LeftBracket : '[');
-		Rune _rightBracket = new Rune (Driver != null ? Driver.RightBracket : ']');
-		Rune _leftDefault = new Rune (Driver != null ? Driver.LeftDefaultIndicator : '<');
-		Rune _rightDefault = new Rune (Driver != null ? Driver.RightDefaultIndicator : '>');
-
 		internal void Update ()
 		{
 			if (IsDefault)
@@ -166,14 +174,6 @@ namespace Terminal.Gui {
 			else
 				shown_text = ustring.Make (_leftBracket) + " " + text + " " + ustring.Make (_rightBracket);
 
-			shown_text = shown_text
-				.Replace ("\f", "\u21a1")		// U+21A1 ↡ DOWNWARDS TWO HEADED ARROW
-				.Replace ("\n", "\u240a")		// U+240A (SYMBOL FOR LINE FEED, ␊)
-				.Replace ("\r", "\u240d")		// U+240D (SYMBOL FOR CARRIAGE RETURN, ␍)
-				.Replace ("\t", "\u2409")		// U+2409 ␉ SYMBOL FOR HORIZONTAL TABULATION
-				.Replace ("\v", "\u240b")		// U+240B ␋ SYMBOL FOR VERTICAL TABULATION
-				.TrimSpace ();
-
 			shown_text = GetTextFromHotKey (shown_text, '_', out hot_pos, out hot_key);
 
 			SetNeedsDisplay ();

UICatalog/Scenarios/CharacterMap.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using Terminal.Gui;
+using Rune = System.Rune;
 
 namespace UICatalog {
 	/// <summary>
@@ -36,6 +37,9 @@ namespace UICatalog {
 			}
 
 			var radioItems = new (ustring radioLabel, int start, int end) [] {
+				CreateRadio("ASCII Control Characterss", 0x00, 0x1F),
+				CreateRadio("C0 Control Characters", 0x80, 0x9f),
+				CreateRadio("Hangul Jamo", 0x1100, 0x11ff),	// This is where wide chars tend to start
 				CreateRadio("Currency Symbols", 0x20A0, 0x20CF),
 				CreateRadio("Letterlike Symbols", 0x2100, 0x214F),
 				CreateRadio("Arrows", 0x2190, 0x21ff),
@@ -57,7 +61,7 @@ namespace UICatalog {
 			jumpList.Y = Pos.Bottom (label);
 			jumpList.Width = Dim.Fill ();
 			jumpList.SelectedItemChanged = (args) => {
-				charMap.Start = radioItems[args.SelectedItem].start;
+				charMap.Start = radioItems [args.SelectedItem].start;
 			};
 
 			Win.Add (jumpList);
@@ -105,6 +109,15 @@ namespace UICatalog {
 #if true
 		private void CharMap_DrawContent (Rect viewport)
 		{
+			//Rune ReplaceNonPrintables (Rune c)
+			//{
+			//	if (c < 0x20) {
+			//		return new Rune (c + 0x2400);         // U+25A1 □ WHITE SQUARE
+			//	} else {
+			//		return c;
+			//	}
+			//}
+
 			for (int header = 0; header < 16; header++) {
 				Move (viewport.X + RowHeaderWidth + (header * 2), 0);
 				Driver.AddStr ($" {header:x} ");
@@ -115,9 +128,12 @@ namespace UICatalog {
 					var rowLabel = $"U+{val / 16:x4}x";
 					Move (0, y + 1);
 					Driver.AddStr (rowLabel);
+					var prevColWasWide = false;
 					for (int col = 0; col < 16; col++) {
-						Move (viewport.X + RowHeaderWidth + (col * 2), 0 + y + 1);
-						Driver.AddStr ($" {(char)((-viewport.Y + row) * 16 + col)}");
+						var rune = new Rune ((uint)((uint)(-viewport.Y + row) * 16 + col));
+						Move (viewport.X + RowHeaderWidth + (col * 2) + (prevColWasWide ? 0 : 1), 0 + y + 1);
+						Driver.AddRune (rune);
+						//prevColWasWide = Rune.ColumnWidth(rune) > 1;
 					}
 				}
 			}

UnitTests/DimTests.cs

@@ -27,9 +27,37 @@ namespace Terminal.Gui {
 			int testVal = 5;
 			dim = Dim.Sized (testVal);
 			Assert.Equal ($"Dim.Absolute({testVal})", dim.ToString ());
+
+			testVal = -1;
+			dim = Dim.Sized (testVal);
+			Assert.Equal ($"Dim.Absolute({testVal})", dim.ToString ());
 		}
 
-		// TODO: Other Dim.Sized tests (e.g. Equal?)
+		[Fact]
+		public void Sized_Equals ()
+		{
+			int n1 = 0;
+			int n2 = 0;
+			var dim1 = Dim.Sized (n1);
+			var dim2 = Dim.Sized (n2);
+			Assert.Equal (dim1, dim2);
+
+			n1 = n2 = 1;
+			dim1 = Dim.Sized (n1);
+			dim2 = Dim.Sized (n2);
+			Assert.Equal (dim1, dim2);
+
+			n1 = n2 = -1;
+			dim1 = Dim.Sized (n1);
+			dim2 = Dim.Sized (n2);
+			Assert.Equal (dim1, dim2);
+
+			n1 = 0;
+			n2 = 1;
+			dim1 = Dim.Sized (n1);
+			dim2 = Dim.Sized (n2);
+			Assert.NotEqual (dim1, dim2);
+		}
 
 		[Fact]
 		public void Width_SetsValue ()
@@ -47,7 +75,46 @@ namespace Terminal.Gui {
 			Assert.Equal ($"DimView(side=Width, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", dim.ToString ());
 		}
 
-		// TODO: Other Dim.Width tests (e.g. Equal?)
+		[Fact]
+		public void Width_Equals ()
+		{
+			var testRect1 = Rect.Empty;
+			var view1 = new View (testRect1);
+			var testRect2 = Rect.Empty;
+			var view2 = new View (testRect2);
+
+			var dim1 = Dim.Width (view1);
+			var dim2 = Dim.Width (view1);
+			// BUGBUG: Dim.Width should support Equals() and this should change to Euqal.
+			Assert.NotEqual (dim1, dim2);
+
+			dim2 = Dim.Width (view2);
+			Assert.NotEqual (dim1, dim2);
+
+			testRect1 = new Rect (0, 1, 2, 3);
+			view1 = new View (testRect1);
+			testRect2 = new Rect (0, 1, 2, 3);
+			dim1 = Dim.Width (view1);
+			dim2 = Dim.Width (view1);
+			// BUGBUG: Dim.Width should support Equals() and this should change to Euqal.
+			Assert.NotEqual (dim1, dim2);
+
+			testRect1 = new Rect (0, -1, -2, -3);
+			view1 = new View (testRect1);
+			testRect2 = new Rect (0, -1, -2, -3);
+			dim1 = Dim.Width (view1);
+			dim2 = Dim.Width (view1);
+			// BUGBUG: Dim.Width should support Equals() and this should change to Euqal.
+			Assert.NotEqual (dim1, dim2);
+
+			testRect1 = new Rect (0, -1, -2, -3);
+			view1 = new View (testRect1);
+			testRect2 = Rect.Empty;
+			view2 = new View (testRect2);
+			dim1 = Dim.Width (view1);
+			dim2 = Dim.Width (view2);
+			Assert.NotEqual (dim1, dim2);
+		}
 
 		[Fact]
 		public void Height_SetsValue ()
@@ -72,7 +139,7 @@ namespace Terminal.Gui {
 		{
 			var testMargin = 0;
 			var dim = Dim.Fill ();
-			Assert.Equal ($"Dim.Fill(margin={testMargin})", dim.ToString());
+			Assert.Equal ($"Dim.Fill(margin={testMargin})", dim.ToString ());
 
 			testMargin = 0;
 			dim = Dim.Fill (testMargin);
@@ -85,7 +152,7 @@ namespace Terminal.Gui {
 
 
 		[Fact]
-		public void Fill_Equal()
+		public void Fill_Equal ()
 		{
 			var margin1 = 0;
 			var margin2 = 0;
@@ -99,19 +166,54 @@ namespace Terminal.Gui {
 		{
 			float f = 0;
 			var dim = Dim.Percent (f);
-			Assert.Equal ($"Dim.Factor({f/100:0.###})", dim.ToString ());
+			Assert.Equal ($"Dim.Factor({f / 100:0.###})", dim.ToString ());
 			f = 0.5F;
 			dim = Dim.Percent (f);
-			Assert.Equal ($"Dim.Factor({f/100:0.###})", dim.ToString ());
+			Assert.Equal ($"Dim.Factor({f / 100:0.###})", dim.ToString ());
 			f = 100;
 			dim = Dim.Percent (f);
-			Assert.Equal ($"Dim.Factor({f/100:0.###})", dim.ToString ());
+			Assert.Equal ($"Dim.Factor({f / 100:0.###})", dim.ToString ());
 		}
 
-		// TODO: Other Dim.Percent tests (e.g. Equal?)
+		[Fact]
+		public void Percent_Equals ()
+		{
+			float n1 = 0;
+			float n2 = 0;
+			var dim1 = Dim.Percent (n1);
+			var dim2 = Dim.Percent (n2);
+			Assert.Equal (dim1, dim2);
+
+			n1 = n2 = 1;
+			dim1 = Dim.Percent (n1);
+			dim2 = Dim.Percent (n2);
+			Assert.Equal (dim1, dim2);
+
+			n1 = n2 = 0.5f;
+			dim1 = Dim.Percent (n1);
+			dim2 = Dim.Percent (n2);
+			Assert.Equal (dim1, dim2);
+
+			n1 = n2 = 100f;
+			dim1 = Dim.Percent (n1);
+			dim2 = Dim.Percent (n2);
+			Assert.Equal (dim1, dim2);
+
+			n1 = 0;
+			n2 = 1;
+			dim1 = Dim.Percent (n1);
+			dim2 = Dim.Percent (n2);
+			Assert.NotEqual (dim1, dim2);
+
+			n1 = 0.5f;
+			n2 = 1.5f;
+			dim1 = Dim.Percent (n1);
+			dim2 = Dim.Percent (n2);
+			Assert.NotEqual (dim1, dim2);
+		}
 
 		[Fact]
-		public void Percent_ThrowsOnIvalid()
+		public void Percent_ThrowsOnIvalid ()
 		{
 			var dim = Dim.Percent (0);
 			Assert.Throws<ArgumentException> (() => dim = Dim.Percent (-1));

UnitTests/PosTests.cs

@@ -1,8 +1,10 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Data;
 using System.IO;
 using System.Linq;
+using System.Runtime.InteropServices.WindowsRuntime;
 using Terminal.Gui;
 using Xunit;
 
@@ -46,6 +48,14 @@ namespace Terminal.Gui {
 			Assert.NotEqual (pos1, pos2);
 		}
 
+		[Fact]
+		public void AnchorEnd_Negative_Throws ()
+		{
+			Pos pos;
+			var n = -1;
+			Assert.Throws<ArgumentException> (() => pos = Pos.AnchorEnd (n));
+		}
+
 		[Fact]
 		public void At_SetsValue ()
 		{
@@ -55,7 +65,8 @@ namespace Terminal.Gui {
 			pos = Pos.At (5);
 			Assert.Equal ("Pos.Absolute(5)", pos.ToString ());
 
-			//Assert.Throws<ArgumentException> (() => pos = Pos.At (-1));
+			pos = Pos.At (-1);
+			Assert.Equal ("Pos.Absolute(-1)", pos.ToString ());
 		}
 
 		[Fact]
@@ -69,79 +80,246 @@ namespace Terminal.Gui {
 			Assert.Equal (pos1, pos2);
 		}
 
-		[Fact]
-		public void Left_SetsValue ()
+		[Fact] 
+		public void SetSide_Null_Throws ()
 		{
 			var pos = Pos.Left (null);
 			Assert.Throws<NullReferenceException> (() => pos.ToString ());
 
-			var testVal = Rect.Empty;
-			pos = Pos.Left (new View ());
-			Assert.Equal ($"Pos.View(side=x, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
+			pos = Pos.X (null);
+			Assert.Throws<NullReferenceException> (() => pos.ToString ());
 
-			pos = Pos.Left (new View (testVal));
-			Assert.Equal ($"Pos.View(side=x, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
+			pos = Pos.Top (null);
+			Assert.Throws<NullReferenceException> (() => pos.ToString ());
+
+			pos = Pos.Y(null);
+			Assert.Throws<NullReferenceException> (() => pos.ToString ());
 
-			testVal = new Rect (1, 2, 3, 4);
-			pos = Pos.Left (new View (testVal));
-			Assert.Equal ($"Pos.View(side=x, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
+			pos = Pos.Bottom (null);
+			Assert.Throws<NullReferenceException> (() => pos.ToString ());
+
+			pos = Pos.Right (null);
+			Assert.Throws<NullReferenceException> (() => pos.ToString ());
 		}
 
 		// TODO: Test Left, Top, Right bottom Equal
 
+		/// <summary>
+		/// Tests Pos.Left, Pos.X, Pos.Top, Pos.Y, Pos.Right, and Pos.Bottom set operations
+		/// </summary>
 		[Fact]
-		public void Top_SetsValue ()
+		public void PosSide_SetsValue ()
 		{
-			var pos = Pos.Top (null);
-			Assert.Throws<NullReferenceException> (() => pos.ToString ());
-
-			var testVal = Rect.Empty;
+			string side; // used in format string
+			var testRect = Rect.Empty;
+			var testInt = 0;
+			Pos pos; 
+
+			// Pos.Left
+			side = "x";
+			testInt = 0;
+			testRect = Rect.Empty;
+			pos = Pos.Left (new View ());
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			pos = Pos.Left (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testRect = new Rect (1, 2, 3, 4);
+			pos = Pos.Left (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			// Pos.Left(win) + 0
+			pos = Pos.Left (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testInt = 1;
+			// Pos.Left(win) +1
+			pos = Pos.Left (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testInt = -1;
+			// Pos.Left(win) -1
+			pos = Pos.Left (new View (testRect)) - testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			// Pos.X
+			side = "x";
+			testInt = 0;
+			testRect = Rect.Empty;
+			pos = Pos.X (new View ());
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			pos = Pos.X (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testRect = new Rect (1, 2, 3, 4);
+			pos = Pos.X (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			// Pos.X(win) + 0
+			pos = Pos.X (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testInt = 1;
+			// Pos.X(win) +1
+			pos = Pos.X (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testInt = -1;
+			// Pos.X(win) -1
+			pos = Pos.X (new View (testRect)) - testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			// Pos.Top
+			side = "y";
+			testInt = 0;
+			testRect = Rect.Empty;
 			pos = Pos.Top (new View ());
-			Assert.Equal ($"Pos.View(side=y, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			pos = Pos.Top (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testRect = new Rect (1, 2, 3, 4);
+			pos = Pos.Top (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			// Pos.Top(win) + 0
+			pos = Pos.Top (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testInt = 1;
+			// Pos.Top(win) +1
+			pos = Pos.Top (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testInt = -1;
+			// Pos.Top(win) -1
+			pos = Pos.Top (new View (testRect)) - testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			// Pos.Y
+			side = "y";
+			testInt = 0;
+			testRect = Rect.Empty;
+			pos = Pos.Y (new View ());
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			pos = Pos.Y (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testRect = new Rect (1, 2, 3, 4);
+			pos = Pos.Y (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			// Pos.Y(win) + 0
+			pos = Pos.Y (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testInt = 1;
+			// Pos.Y(win) +1
+			pos = Pos.Y (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			testInt = -1;
+			// Pos.Y(win) -1
+			pos = Pos.Y (new View (testRect)) - testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
+
+			// Pos.Bottom
+			side = "bottom";
+			testRect = Rect.Empty;
+			testInt = 0;
+			pos = Pos.Bottom (new View ());
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
 
-			testVal = new Rect (1, 2, 3, 4);
-			pos = Pos.Top (new View (testVal));
-			Assert.Equal ($"Pos.View(side=y, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
-		}
+			pos = Pos.Bottom (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
 
-		[Fact]
-		public void Right_SetsValue ()
-		{
-			var pos = Pos.Right (null);
-			Assert.Throws<NullReferenceException> (() => pos.ToString ());
+			testRect = new Rect (1, 2, 3, 4);
+			pos = Pos.Bottom (new View (testRect));
+			Assert.Equal ($"Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}})){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
 
-			var testVal = Rect.Empty;
-			pos = Pos.Right (new View ());
-			Assert.Equal ($"Pos.View(side=right, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
+			// Pos.Bottom(win) + 0
+			pos = Pos.Bottom (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
 
-			testVal = Rect.Empty;
-			pos = Pos.Right (new View (testVal));
-			Assert.Equal ($"Pos.View(side=right, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
+			testInt = 1;
+			// Pos.Bottom(win) +1
+			pos = Pos.Bottom (new View (testRect)) + testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
 
-			testVal = new Rect (1, 2, 3, 4);
-			pos = Pos.Right (new View (testVal));
-			Assert.Equal ($"Pos.View(side=right, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
+			testInt = -1;
+			// Pos.Bottom(win) -1
+			pos = Pos.Bottom (new View (testRect)) - testInt;
+			Assert.Equal ($"Pos.Combine(Pos.Combine(Pos.View(side={side}, target=View()({{X={testRect.X},Y={testRect.Y},Width={testRect.Width},Height={testRect.Height}}}))+Pos.Absolute(0)){(testInt < 0 ? '-' : '+')}Pos.Absolute({testInt}))", pos.ToString ());
 		}
 
+		// See: https://github.com/migueldeicaza/gui.cs/issues/504
 		[Fact]
-		public void Bottom_SetsValue ()
+		public void LeftTopBottomRight_Win_ShouldNotThrow ()
 		{
-			var pos = Pos.Bottom (null);
-			Assert.Throws<NullReferenceException> (() => pos.ToString ());
-
-			var testVal = Rect.Empty;
-			pos = Pos.Bottom (new View ());
-			Assert.Equal ($"Pos.View(side=bottom, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
-
-			testVal = Rect.Empty;
-			pos = Pos.Bottom (new View (testVal));
-			Assert.Equal ($"Pos.View(side=bottom, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
+			// Setup Fake driver
+			(Window win, Button button) setup ()
+			{
+				Application.Init (new FakeDriver (), new NetMainLoop (() => FakeConsole.ReadKey (true)));
+				Application.Iteration = () => {
+					Application.RequestStop ();
+				};
+				var win = new Window ("window") {
+					X = 0,
+					Y = 0,
+					Width = Dim.Fill (),
+					Height = Dim.Fill (),
+				};
+				Application.Top.Add (win);
+
+				var button = new Button ("button") {
+					X = Pos.Center (),
+				};
+				win.Add (button);
+
+				return (win, button);
+			}
+
+			void cleanup ()
+			{
+				// Cleanup
+				Application.Shutdown ();
+			}
+
+			// Test cases:
+			var app = setup ();
+			app.button.Y = Pos.Left (app.win);
+			Application.Run ();
+			cleanup ();
+
+			app = setup ();
+			app.button.Y = Pos.X (app.win);
+			Application.Run ();
+			cleanup ();
+
+			app = setup ();
+			app.button.Y = Pos.Top (app.win);
+			Application.Run ();
+			cleanup ();
+
+			app = setup ();
+			app.button.Y = Pos.Y (app.win);
+			Application.Run ();
+			cleanup ();
+
+			app = setup ();
+			app.button.Y = Pos.Bottom (app.win);
+			Application.Run ();
+			cleanup ();
+
+			app = setup ();
+			app.button.Y = Pos.Right (app.win);
+			Application.Run ();
+			cleanup ();
 
-			testVal = new Rect (1, 2, 3, 4);
-			pos = Pos.Bottom (new View (testVal));
-			Assert.Equal ($"Pos.View(side=bottom, target=View()({{X={testVal.X},Y={testVal.Y},Width={testVal.Width},Height={testVal.Height}}}))", pos.ToString ());
-
-			//Assert.Throws<ArgumentException> (() => pos = Pos.Bottom (new View (new Rect (0, 0, -3, -4))));
 		}
 
 		[Fact]
@@ -186,6 +364,9 @@ namespace Terminal.Gui {
 			Assert.Throws<ArgumentException> (() => pos = Pos.Percent (1000001));
 		}
 
+		// TODO: Test PosCombine
+
+
 		// TODO: Test operators
 	}
 }