LT-22725: Show abbreviation for user-defined natural classes (#1158)

* LT-22725: Show abbreviation for user-defined natural classes

In the phonological rule formula, a feature-based natural class was
always drawn as its list of features, even when the user had built
and named the class. Only classes abbreviated "C" or "V" showed
their abbreviation, and only when they had a single feature.

The rule view now draws a user-defined feature-based natural class
as its abbreviation in brackets, whatever its number of features.
An empty abbreviation displays as "***". Classes created
automatically when features are inserted directly into a rule
still display their features.

A class counts as user-defined when it has a name that is not
auto-generated. That check now takes the natural class as an
argument, so the view can apply it to each class it draws rather
than to the current selection. Line count and width use the same
check, so the cell is sized to the abbreviation.

Register the display dependencies on NC's name and abbreviation
for displaying phonological & affix process rules. This ensures
if names or abbreviations are updated, the display widths are
recalculated so new names/abbreviations fit.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: aror92

Src/LexText/Morphology/AffixRuleFormulaVc.cs

@@ -160,6 +160,8 @@ public override void Display(IVwEnv vwenv, int hvo, int frag)
 
 					var ctxtLens = new VwLength[m_rule.InputOS.Count];
 					vwenv.NoteDependency(new[] {m_rule.Hvo}, new[] {MoAffixProcessTags.kflidInput}, 1 );
+					// Column widths below are fixed from each input natural class.
+					NoteNaturalClassDependencies(vwenv, m_rule.InputOS);
 					for (int i = 0; i < m_rule.InputOS.Count; i++)
 					{
 						int idxWidth = GetStrWidth(TsStringUtils.MakeString(Convert.ToString(i + 1), userWs), m_indexProps, vwenv);

Src/LexText/Morphology/MetaRuleFormulaVc.cs

@@ -93,6 +93,7 @@ public override void Display(IVwEnv vwenv, int hvo, int frag)
 			{
 				case kfragRule:
 					m_rule = m_cache.ServiceLocator.GetInstance<IPhMetathesisRuleRepository>().GetObject(hvo);
+					NoteNaturalClassDependencies(vwenv, m_rule.StrucDescOS);
 					if (m_rule.Disabled)
 					{
 						vwenv.set_StringProperty((int)FwTextPropType.ktptNamedStyle, "Disabled Text");

Src/LexText/Morphology/RegRuleFormulaVc.cs

@@ -85,6 +85,8 @@ public override void Display(IVwEnv vwenv, int hvo, int frag)
 				case kfragRHS:
 					m_rhs = m_cache.ServiceLocator.GetInstance<IPhSegRuleRHSRepository>().GetObject(hvo);
 					var rule = m_rhs.OwningRule;
+					NoteNaturalClassDependencies(vwenv, rule.StrucDescOS, m_rhs.StrucChangeOS,
+						new IPhContextOrVar[] { m_rhs.LeftContextOA, m_rhs.RightContextOA });
 					if (rule.Disabled)
 					{
 						vwenv.set_StringProperty((int)FwTextPropType.ktptNamedStyle, "Disabled Text");

Src/LexText/Morphology/RuleFormulaControl.cs

@@ -997,7 +997,18 @@ public bool IsFeatureBasedNCNameUserDefined()
 			if (!IsFeatsNCContextCurrent){ return false; }
 
 			var ctxt = (IPhSimpleContextNC) CurrentContext;
-			var natClass = (IPhNCFeatures)ctxt.FeatureStructureRA;
+			return IsFeatureBasedNCNameUserDefined((IPhNCFeatures)ctxt.FeatureStructureRA);
+		}
+
+		/// <summary>
+		/// Reports whether a feature-based natural class carries a name the user gave it,
+		/// as opposed to no name or the name generated when phonological features are inserted
+		/// directly into a rule. Returns false when <paramref name="natClass"/> is null.
+		/// </summary>
+		public static bool IsFeatureBasedNCNameUserDefined(IPhNCFeatures natClass)
+		{
+			if (natClass == null)
+				return false;
 
 			// Get the auto-generated text that precedes the rulename. (e.g. extracting "Created automatically for rule "" from "Created automatically for rule "{0}"")
 			// Note that the generated rulename following the stubtext is different for "regular" vs affix rules, but in all cases the auto-generated stub is the same.

Src/LexText/Morphology/RuleFormulaVcBase.cs

@@ -1,4 +1,4 @@
-// Copyright (c) 2015 SIL International
+// Copyright (c) 2015 SIL International
 // This software is licensed under the LGPL, version 2.1 or later
 // (http://www.gnu.org/licenses/lgpl-2.1.html)
 
@@ -39,6 +39,9 @@ public abstract class RuleFormulaVcBase : PatternVcBase
 		// variant frags
 		public const int kfragXVariable = 113;
 
+		public const int kfragNCAbbreviation = 114;
+		public const int kfragStars = 115;
+
 		// fake flids
 		public const int ktagFeature = -200;
 		public const int ktagVariable = -201;
@@ -49,6 +52,7 @@ public abstract class RuleFormulaVcBase : PatternVcBase
 
 		protected ITsString m_infinity;
 		protected ITsString m_x;
+		protected ITsString m_stars;
 
 		protected RuleFormulaVcBase(LcmCache cache, PropertyTable propertyTable)
 			: base(cache, propertyTable)
@@ -57,6 +61,7 @@ protected RuleFormulaVcBase(LcmCache cache, PropertyTable propertyTable)
 			m_propertyTable = propertyTable;
 			m_infinity = TsStringUtils.MakeString("\u221e", userWs);
 			m_x = TsStringUtils.MakeString("X", userWs);
+			m_stars = TsStringUtils.MakeString("***", userWs);
 		}
 
 		/// <summary>
@@ -77,6 +82,20 @@ public override void Display(IVwEnv vwenv, int hvo, int frag)
 		{
 			switch (frag)
 			{
+				// If there is no writing system for the abbreviation,
+				// or the abbreviation is empty, display kfragStars as fallback.
+				case kfragNCAbbreviation:
+					int abbrWs = WritingSystemServices.ActualWs(m_cache, WritingSystemServices.kwsFirstAnal, hvo,
+						PhNaturalClassTags.kflidAbbreviation);
+					ITsString abbr = abbrWs != 0
+						? m_cache.MainCacheAccessor.get_MultiStringAlt(hvo, PhNaturalClassTags.kflidAbbreviation, abbrWs)
+						: null;
+					if (abbr != null && abbr.Length > 0)
+						vwenv.AddStringAltMember(PhNaturalClassTags.kflidAbbreviation, abbrWs, this);
+					else
+						vwenv.AddProp(PhNaturalClassTags.kflidAbbreviation, this, kfragStars);
+					break;
+
 				case kfragContext:
 					var ctxtOrVar = m_cache.ServiceLocator.GetInstance<IPhContextOrVarRepository>().GetObject(hvo);
 					bool isOuterIterCtxt = false;
@@ -114,83 +133,95 @@ public override void Display(IVwEnv vwenv, int hvo, int frag)
 								// Natural class simple context with a feature-based natural class
 								var natClass = (IPhNCFeatures) ncCtxt.FeatureStructureRA;
 
-								int numLines = GetNumLines(ncCtxt);
-								if (numLines == 0)
+								// User-defined feature-based natural classes should display
+								// only the abbreviation.
+								if (RuleFormulaControl.IsFeatureBasedNCNameUserDefined(natClass))
 								{
 									if (!isOuterIterCtxt)
 										OpenSingleLinePile(vwenv, GetMaxNumLines());
 
+									// use normal brackets around abbreviation
 									vwenv.AddProp(ktagInnerNonBoundary, this, kfragLeftBracket);
-									vwenv.AddProp(PhSimpleContextNCTags.kflidFeatureStructure, this, kfragQuestions);
+
+									vwenv.AddObjProp(PhSimpleContextNCTags.kflidFeatureStructure, this, kfragNCAbbreviation);
+
 									vwenv.AddProp(ktagInnerNonBoundary, this, kfragRightBracket);
 
 									if (!isOuterIterCtxt)
 										CloseSingleLinePile(vwenv);
 								}
-								else if (numLines == 1)
+								else
 								{
-									if (!isOuterIterCtxt)
-										OpenSingleLinePile(vwenv, GetMaxNumLines());
+									int numLines = GetNumLines(ncCtxt);
+									if (numLines == 0)
+									{
+										if (!isOuterIterCtxt)
+											OpenSingleLinePile(vwenv, GetMaxNumLines());
 
-									// use normal brackets for a single line context
-									vwenv.AddProp(ktagInnerNonBoundary, this, kfragLeftBracket);
+										vwenv.AddProp(ktagInnerNonBoundary, this, kfragLeftBracket);
+										vwenv.AddProp(PhSimpleContextNCTags.kflidFeatureStructure, this, kfragQuestions);
+										vwenv.AddProp(ktagInnerNonBoundary, this, kfragRightBracket);
 
-									// special consonant and vowel natural classes only display the abbreviation
-									if (natClass.Abbreviation.AnalysisDefaultWritingSystem.Text == "C"
-										|| natClass.Abbreviation.AnalysisDefaultWritingSystem.Text == "V")
-									{
-										vwenv.AddObjProp(PhSimpleContextNCTags.kflidFeatureStructure, this, kfragNC);
+										if (!isOuterIterCtxt)
+											CloseSingleLinePile(vwenv);
 									}
-									else
+									else if (numLines == 1)
 									{
+										if (!isOuterIterCtxt)
+											OpenSingleLinePile(vwenv, GetMaxNumLines());
+
+										// use normal brackets for a single line context
+										vwenv.AddProp(ktagInnerNonBoundary, this, kfragLeftBracket);
+
 										if (natClass.FeaturesOA != null && natClass.FeaturesOA.FeatureSpecsOC.Count > 0)
 											vwenv.AddObjProp(PhSimpleContextNCTags.kflidFeatureStructure, this, kfragFeatNC);
 										else if (ncCtxt.PlusConstrRS.Count > 0)
 											vwenv.AddObjVecItems(PhSimpleContextNCTags.kflidPlusConstr, this, kfragPlusVariable);
 										else
 											vwenv.AddObjVecItems(PhSimpleContextNCTags.kflidMinusConstr, this, kfragMinusVariable);
-									}
-									vwenv.AddProp(ktagInnerNonBoundary, this, kfragRightBracket);
 
-									if (!isOuterIterCtxt)
-										CloseSingleLinePile(vwenv);
-								}
-								else
-								{
-									// multiline context
-
-									// left bracket pile
-									int maxNumLines = GetMaxNumLines();
-									vwenv.Props = m_bracketProps;
-									vwenv.set_IntProperty((int)FwTextPropType.ktptMarginLeading, (int)FwTextPropVar.ktpvMilliPoint, PileMargin);
-									vwenv.OpenInnerPile();
-									AddExtraLines(maxNumLines - numLines, ktagLeftNonBoundary, vwenv);
-									vwenv.AddProp(ktagLeftNonBoundary, this, kfragLeftBracketUpHook);
-									for (int i = 1; i < numLines - 1; i++)
-										vwenv.AddProp(ktagLeftNonBoundary, this, kfragLeftBracketExt);
-									vwenv.AddProp(ktagLeftBoundary, this, kfragLeftBracketLowHook);
-									vwenv.CloseInnerPile();
-
-									// feature and variable pile
-									vwenv.set_IntProperty((int)FwTextPropType.ktptAlign, (int)FwTextPropVar.ktpvEnum, (int)FwTextAlign.ktalLeft);
-									vwenv.OpenInnerPile();
-									AddExtraLines(maxNumLines - numLines, vwenv);
-									vwenv.AddObjProp(PhSimpleContextNCTags.kflidFeatureStructure, this, kfragFeatNC);
-									vwenv.AddObjVecItems(PhSimpleContextNCTags.kflidPlusConstr, this, kfragPlusVariable);
-									vwenv.AddObjVecItems(PhSimpleContextNCTags.kflidMinusConstr, this, kfragMinusVariable);
-									vwenv.CloseInnerPile();
-
-									// right bracket pile
-									vwenv.Props = m_bracketProps;
-									if (!isOuterIterCtxt)
-										vwenv.set_IntProperty((int)FwTextPropType.ktptMarginTrailing, (int)FwTextPropVar.ktpvMilliPoint, PileMargin);
-									vwenv.OpenInnerPile();
-									AddExtraLines(maxNumLines - numLines, ktagRightNonBoundary, vwenv);
-									vwenv.AddProp(ktagRightNonBoundary, this, kfragRightBracketUpHook);
-									for (int i = 1; i < numLines - 1; i++)
-										vwenv.AddProp(ktagRightNonBoundary, this, kfragRightBracketExt);
-									vwenv.AddProp(ktagRightBoundary, this, kfragRightBracketLowHook);
-									vwenv.CloseInnerPile();
+										vwenv.AddProp(ktagInnerNonBoundary, this, kfragRightBracket);
+
+										if (!isOuterIterCtxt)
+											CloseSingleLinePile(vwenv);
+									}
+									else
+									{
+										// multiline context
+
+										// left bracket pile
+										int maxNumLines = GetMaxNumLines();
+										vwenv.Props = m_bracketProps;
+										vwenv.set_IntProperty((int)FwTextPropType.ktptMarginLeading, (int)FwTextPropVar.ktpvMilliPoint, PileMargin);
+										vwenv.OpenInnerPile();
+										AddExtraLines(maxNumLines - numLines, ktagLeftNonBoundary, vwenv);
+										vwenv.AddProp(ktagLeftNonBoundary, this, kfragLeftBracketUpHook);
+										for (int i = 1; i < numLines - 1; i++)
+											vwenv.AddProp(ktagLeftNonBoundary, this, kfragLeftBracketExt);
+										vwenv.AddProp(ktagLeftBoundary, this, kfragLeftBracketLowHook);
+										vwenv.CloseInnerPile();
+
+										// feature and variable pile
+										vwenv.set_IntProperty((int)FwTextPropType.ktptAlign, (int)FwTextPropVar.ktpvEnum, (int)FwTextAlign.ktalLeft);
+										vwenv.OpenInnerPile();
+										AddExtraLines(maxNumLines - numLines, vwenv);
+										vwenv.AddObjProp(PhSimpleContextNCTags.kflidFeatureStructure, this, kfragFeatNC);
+										vwenv.AddObjVecItems(PhSimpleContextNCTags.kflidPlusConstr, this, kfragPlusVariable);
+										vwenv.AddObjVecItems(PhSimpleContextNCTags.kflidMinusConstr, this, kfragMinusVariable);
+										vwenv.CloseInnerPile();
+
+										// right bracket pile
+										vwenv.Props = m_bracketProps;
+										if (!isOuterIterCtxt)
+											vwenv.set_IntProperty((int)FwTextPropType.ktptMarginTrailing, (int)FwTextPropVar.ktpvMilliPoint, PileMargin);
+										vwenv.OpenInnerPile();
+										AddExtraLines(maxNumLines - numLines, ktagRightNonBoundary, vwenv);
+										vwenv.AddProp(ktagRightNonBoundary, this, kfragRightBracketUpHook);
+										for (int i = 1; i < numLines - 1; i++)
+											vwenv.AddProp(ktagRightNonBoundary, this, kfragRightBracketExt);
+										vwenv.AddProp(ktagRightBoundary, this, kfragRightBracketLowHook);
+										vwenv.CloseInnerPile();
+									}
 								}
 							}
 							else
@@ -360,6 +391,10 @@ public override ITsString DisplayVariant(IVwEnv vwenv, int tag, int frag)
 					tss = m_x;
 					break;
 
+				case kfragStars:
+					tss = m_stars;
+					break;
+
 				default:
 					tss = base.DisplayVariant(vwenv, tag, frag);
 					break;
@@ -428,6 +463,51 @@ void DisplayIterCtxt(int numLines, IVwEnv vwenv)
 			vwenv.CloseInnerPile();
 		}
 
+		/// <summary>
+		/// Makes the fragment being displayed depend on the name and abbreviation of every
+		/// feature-based natural class in the given contexts, including those nested in sequence
+		/// and iteration contexts. Changing either property then rebuilds the whole fragment, so
+		/// the choice between abbreviation and feature list, line counts and cell widths are all
+		/// recomputed. Null contexts are ignored.
+		/// </summary>
+		protected static void NoteNaturalClassDependencies(IVwEnv vwenv,
+			params IEnumerable<IPhContextOrVar>[] contextGroups)
+		{
+			var hvos = new List<int>();
+			var tags = new List<int>();
+			foreach (IEnumerable<IPhContextOrVar> group in contextGroups)
+			{
+				foreach (IPhContextOrVar ctxtOrVar in group)
+					CollectFeatureNaturalClasses(ctxtOrVar, hvos, tags);
+			}
+			if (hvos.Count > 0)
+				vwenv.NoteDependency(hvos.ToArray(), tags.ToArray(), hvos.Count);
+		}
+
+		private static void CollectFeatureNaturalClasses(IPhContextOrVar ctxtOrVar,
+			List<int> hvos, List<int> tags)
+		{
+			switch (ctxtOrVar)
+			{
+				case IPhSequenceContext seqCtxt:
+					foreach (IPhPhonContext member in seqCtxt.MembersRS)
+						CollectFeatureNaturalClasses(member, hvos, tags);
+					break;
+
+				case IPhIterationContext iterCtxt:
+					CollectFeatureNaturalClasses(iterCtxt.MemberRA, hvos, tags);
+					break;
+
+				case IPhSimpleContextNC ncCtxt
+					when ncCtxt.FeatureStructureRA is IPhNCFeatures natClass:
+					hvos.Add(natClass.Hvo);
+					tags.Add(PhNaturalClassTags.kflidName);
+					hvos.Add(natClass.Hvo);
+					tags.Add(PhNaturalClassTags.kflidAbbreviation);
+					break;
+			}
+		}
+
 		/// <summary>
 		/// Gets the maximum number of lines to display the specified sequence of simple contexts.
 		/// </summary>
@@ -478,6 +558,13 @@ protected int GetNumLines(IPhContextOrVar ctxtOrVar)
 					if (ncCtxt.FeatureStructureRA != null && ncCtxt.FeatureStructureRA.ClassID == PhNCFeaturesTags.kClassId)
 					{
 						var natClass = (IPhNCFeatures) ncCtxt.FeatureStructureRA;
+
+						// User-defined, feature-based natural classes should display
+						// only the abbreviation, which is a single line.
+						if (RuleFormulaControl.IsFeatureBasedNCNameUserDefined(natClass))
+							return 1;
+
+						// Otherwise, the list of features is displayed.
 						if (natClass.FeaturesOA != null)
 							numFeats = natClass.FeaturesOA.FeatureSpecsOC.Count;
 					}
@@ -589,19 +676,22 @@ int GetNCCtxtWidth(IPhSimpleContextNC ctxt, IVwEnv vwenv)
 		{
 			if (ctxt.FeatureStructureRA != null && ctxt.FeatureStructureRA.ClassID == PhNCFeaturesTags.kClassId)
 			{
+				// User-defined feature-based natural classes display only the abbreviation,
+				// so get width of the abbreviation.
+				var natClass = (IPhNCFeatures)ctxt.FeatureStructureRA;
+				if (RuleFormulaControl.IsFeatureBasedNCNameUserDefined(natClass))
+				{
+					int len = GetStrWidth(ctxt.FeatureStructureRA.Abbreviation.BestAnalysisAlternative, null, vwenv);
+					len += GetStrWidth(m_leftBracket, null, vwenv);
+					len += GetStrWidth(m_rightBracket, null, vwenv);
+					return len;
+				}
+
 				int numLines = GetNumLines(ctxt);
 				if (numLines == 1)
 				{
 					int len;
-					if (ctxt.FeatureStructureRA.Abbreviation.UserDefaultWritingSystem.Text == "C"
-						|| ctxt.FeatureStructureRA.Abbreviation.UserDefaultWritingSystem.Text == "V")
-					{
-						len = GetStrWidth(ctxt.FeatureStructureRA.Abbreviation.BestAnalysisAlternative, null, vwenv);
-					}
-					else
-					{
-						len = GetNCFeatsWidth(ctxt, vwenv);
-					}
+					len = GetNCFeatsWidth(ctxt, vwenv);
 					len += GetStrWidth(m_leftBracket, null, vwenv);
 					len += GetStrWidth(m_rightBracket, null, vwenv);
 					return len;