Merge pull request #19690 from ramezgerges/last_trailing_space_click

fix(textbox): correctly set selection when clicking past the end in a TextBox that ends with spaces

Author: ramezgerges

src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Controls/Given_TextBox.skia.cs

@@ -21,6 +21,7 @@
 using Color = Windows.UI.Color;
 using Point = Windows.Foundation.Point;
 using System.Runtime.InteropServices;
+using Windows.Foundation;
 using SamplesApp.UITests;
 
 namespace Uno.UI.RuntimeTests.Tests.Windows_UI_Xaml_Controls
@@ -935,6 +936,41 @@ public async Task When_Pointer_Tap()
 			Assert.AreEqual(0, SUT.SelectionLength);
 		}
 
+		[TestMethod]
+		public async Task When_Pointer_Tap_After_Ending_Spaces()
+		{
+			using var _ = new TextBoxFeatureConfigDisposable();
+
+			var SUT = new TextBox
+			{
+				Width = 350,
+				Text = "Hello world          ",
+				FontFamily = "Arial" // no Segoe UI on Linux, so we set something common
+			};
+
+			WindowHelper.WindowContent = SUT;
+
+			await WindowHelper.WaitForIdle();
+			await WindowHelper.WaitForLoaded(SUT);
+
+			SUT.Focus(FocusState.Programmatic);
+			await WindowHelper.WaitForIdle();
+
+			var injector = InputInjector.TryCreate() ?? throw new InvalidOperationException("Failed to init the InputInjector");
+			using var mouse = injector.GetMouse();
+
+			var bounds = SUT.GetAbsoluteBounds();
+			mouse.MoveTo(new Point(bounds.Right - 30, bounds.GetMidY()));
+			await WindowHelper.WaitForIdle();
+
+			mouse.Press();
+			mouse.Release();
+			await WindowHelper.WaitForIdle();
+
+			Assert.AreEqual(SUT.Text.Length, SUT.SelectionStart);
+			Assert.AreEqual(0, SUT.SelectionLength);
+		}
+
 		[TestMethod]
 		public async Task When_Pointer_Shift_Tap()
 		{

src/Uno.UI/UI/Xaml/Documents/InlineCollection.skia.cs

@@ -893,7 +893,12 @@ private int GetIndexAtUnadjusted(Point p, bool ignoreEndingSpace, bool extendedS
 				characterCount++;
 			}
 
-			if (ignoreEndingSpace && span == line.SegmentSpans[^1] && span.GlyphsStart + span.GlyphsLength > 0 && char.IsWhiteSpace(segment.Text[span.GlyphsStart + span.GlyphsLength - 1]))
+			if (ignoreEndingSpace
+				&& span == line.SegmentSpans[^1]
+				&& line != _renderLines[^1]
+				&& ((IBlock)_collection.GetParent()).TextWrapping != TextWrapping.NoWrap
+				&& span.GlyphsStart + span.GlyphsLength > 0
+				&& char.IsWhiteSpace(segment.Text[span.GlyphsStart + span.GlyphsLength - 1]))
 			{
 				// in cases like clicking at the end of a line that ends in a wrapping space, we actually want the character right before the space
 				characterCount--;