Apply RawTextPane's invisible-space toggles without a broadcast

Src/LexText/Interlinear/ITextDllTests/RawTextPaneTests.cs

@@ -0,0 +1,136 @@
+// Copyright (c) 2026 SIL International
+// This software is licensed under the LGPL, version 2.1 or later
+// (http://www.gnu.org/licenses/lgpl-2.1.html)
+
+using System.Windows.Forms;
+using System.Xml;
+using NUnit.Framework;
+using SIL.LCModel;
+using SIL.LCModel.Core.Text;
+using SIL.LCModel.Infrastructure;
+using XCore;
+
+namespace SIL.FieldWorks.IText
+{
+	/// <summary>
+	/// Tests that the Baseline pane's ShowInvisibleSpaces and ClickInvisibleSpace handlers
+	/// apply each other's effect directly instead of broadcasting the other property.
+	/// </summary>
+	[TestFixture]
+	public class RawTextPaneTests : MemoryOnlyBackendProviderTestBase
+	{
+		private IStText m_stText;
+		private Mediator m_mediator;
+		private PropertyTable m_propertyTable;
+		private TestRawTextPane m_pane;
+
+		[OneTimeSetUp]
+		public override void FixtureSetup()
+		{
+			base.FixtureSetup();
+			NonUndoableUnitOfWorkHelper.Do(Cache.ActionHandlerAccessor, () =>
+			{
+				m_stText = Cache.ServiceLocator.GetInstance<IStTextFactory>().Create();
+				Cache.ServiceLocator.GetInstance<ITextFactory>().Create().ContentsOA = m_stText;
+				m_stText.AddNewTextPara(null).Contents =
+					TsStringUtils.MakeString("xxxa xxxb xxxc.", Cache.DefaultVernWs);
+			});
+		}
+
+		[SetUp]
+		public override void TestSetup()
+		{
+			base.TestSetup();
+			m_mediator = new Mediator();
+			m_mediator.AddColleague(new ListeningColleague());
+			m_propertyTable = new PropertyTable(m_mediator);
+			// Reading a missing property stores and broadcasts its default
+			m_propertyTable.SetProperty("ShowInvisibleSpaces", false, false);
+			m_propertyTable.SetProperty("ClickInvisibleSpace", false, false);
+			m_pane =new TestRawTextPane(Cache, m_mediator, m_propertyTable, m_stText.Hvo);
+		}
+
+		[TearDown]
+		public override void TestTearDown()
+		{
+			m_pane.Dispose();
+			m_propertyTable.Dispose();
+			m_mediator.Dispose();
+			base.TestTearDown();
+		}
+
+		[Test]
+		public void ClickInvisibleSpaceOn_SpacesHidden_ShowsSpacesWithoutBroadcast()
+		{
+			// SUT
+			ChooseMenuItem("ClickInvisibleSpace", true);
+
+			Assert.That(m_propertyTable.GetBoolProperty("ShowInvisibleSpaces", false), Is.True);
+			Assert.That(m_pane.SpacesShown, Is.True, "the pane must show the spaces itself");
+			Assert.That(m_mediator.JobItems, Is.Zero, "ShowInvisibleSpaces must change without a broadcast");
+		}
+
+		[Test]
+		public void ShowInvisibleSpacesOff_ClickInsertsOn_EndsClickInsertsWithoutBroadcast()
+		{
+			ChooseMenuItem("ShowInvisibleSpaces", true);
+			ChooseMenuItem("ClickInvisibleSpace", true);
+
+			// SUT
+			ChooseMenuItem("ShowInvisibleSpaces", false);
+
+			Assert.That(m_propertyTable.GetBoolProperty("ClickInvisibleSpace", true), Is.False);
+			Assert.That(m_pane.SpacesShown, Is.False);
+			Assert.That(m_mediator.JobItems, Is.Zero, "ClickInvisibleSpace must change without a broadcast");
+
+			// The pane must also have recorded that click-insert is off, or turning it on
+			// again would be taken for no change and leave the spaces hidden.
+			ChooseMenuItem("ClickInvisibleSpace", true);
+			Assert.That(m_propertyTable.GetBoolProperty("ShowInvisibleSpaces", false), Is.True);
+			Assert.That(m_pane.SpacesShown, Is.True);
+		}
+
+		/// <summary>
+		/// Sets the property as the menu item's click does and delivers the broadcast to the
+		/// pane, so a test only counts the broadcasts the pane makes itself.
+		/// </summary>
+		private void ChooseMenuItem(string property, bool value)
+		{
+			m_propertyTable.SetProperty(property, value, false);
+			m_pane.OnPropertyChanged(property);
+		}
+
+		/// <summary>
+		/// A colleague registered so the Mediator queues broadcasts: with no colleague it
+		/// discards them before queueing, and the job count would prove nothing.
+		/// </summary>
+		private sealed class ListeningColleague : IxCoreColleague
+		{
+			public void Init(Mediator mediator, PropertyTable propertyTable, XmlNode configurationParameters) { }
+			public IxCoreColleague[] GetMessageTargets() => new IxCoreColleague[] { this };
+			public bool ShouldNotCall => false;
+			public int Priority => (int)ColleaguePriority.High;
+		}
+
+		/// <summary>
+		/// A laid-out pane on the given text with an insertion point, so a redraw can keep
+		/// the selection.
+		/// </summary>
+		private sealed class TestRawTextPane : RawTextPane
+		{
+			internal TestRawTextPane(LcmCache cache, Mediator mediator, PropertyTable propertyTable, int hvoText)
+			{
+				Cache = cache;
+				m_mediator = mediator;
+				m_propertyTable = propertyTable;
+				Width = 300;
+				Height = 300;
+				SetRoot(hvoText);
+				OnLayout(new LayoutEventArgs(this, "Bounds"));
+				RootBox.MakeSimpleSel(true, true, false, true);
+			}
+
+			internal bool SpacesShown => ((ShowSpaceDecorator)RootBox.DataAccess).ShowSpaces;
+		}
+	}
+}

Src/LexText/Interlinear/RawTextPane.cs

@@ -349,13 +349,7 @@ public override void OnPropertyChanged(string name)
 					break;
 				case "ShowInvisibleSpaces":
 					newVal = ShowInvisibleSpaces;
-					if (newVal != m_showSpaceDa.ShowSpaces)
-					{
-						m_showSpaceDa.ShowSpaces = newVal;
-						var saveSelection = SelectionHelper.Create(this);
-						m_rootb.Reconstruct();
-						saveSelection.SetSelection(true);
-					}
+					ApplyShowInvisibleSpaces(newVal);
 					if (!newVal && ClickInvisibleSpace)
 						TurnOffClickInvisibleSpace();
 					break;
@@ -380,20 +374,41 @@ private void SetParaToReparse(IStTxtPara para)
 				NonUndoableUnitOfWorkHelper.Do(Cache.ActionHandlerAccessor, () => para.ParseIsCurrent = false);
 		}
 
+		/// <summary>
+		/// Turns on ShowInvisibleSpaces and redraws here; the set does not broadcast,
+		/// because this pane is its only listener.
+		/// </summary>
 		private void TurnOnShowInvisibleSpaces()
 		{
-			if (m_propertyTable != null)
-			{
-				m_propertyTable.SetProperty("ShowInvisibleSpaces", true, true);
-			}
+			if (m_propertyTable == null)
+				return;
+			m_propertyTable.SetProperty("ShowInvisibleSpaces", true, false);
+			ApplyShowInvisibleSpaces(true);
 		}
 
+		/// <summary>
+		/// Turns off ClickInvisibleSpace and records it here; the set does not broadcast,
+		/// because this pane is its only listener.
+		/// </summary>
 		private void TurnOffClickInvisibleSpace()
 		{
-			if (m_propertyTable != null)
-			{
-				m_propertyTable.SetProperty("ClickInvisibleSpace", false, true);
-			}
+			if (m_propertyTable == null)
+				return;
+			m_propertyTable.SetProperty("ClickInvisibleSpace", false, false);
+			m_fClickInsertsZws = false;
+		}
+
+		/// <summary>
+		/// Redraws the text, keeping the selection, when invisible spaces are shown or hidden.
+		/// </summary>
+		private void ApplyShowInvisibleSpaces(bool show)
+		{
+			if (show == m_showSpaceDa.ShowSpaces)
+				return;
+			m_showSpaceDa.ShowSpaces = show;
+			var saveSelection = SelectionHelper.Create(this);
+			m_rootb.Reconstruct();
+			saveSelection?.SetSelection(true);
 		}
 
 		private bool ShowInvisibleSpaces