Fix LT-21976: Merge dialect labels on duplicated entries in import

src/SIL.LCModel/Application/ApplicationServices/XmlImportData.cs

@@ -473,6 +473,7 @@ private void MergeRedundantEntries(ILexEntry leOld, ILexEntry leNew)
 				leNew.SensesOS.Add(rgls[i]);
 			MergeDates(leOld, leNew);
 			MergeEntryRefs(leOld, leNew);
+			MergeDialectLabels(leOld, leNew);
 			CopyCustomFieldData(leOld, leNew);
 
 			// Clean up our internal Id map before deleting anything.
@@ -481,6 +482,16 @@ private void MergeRedundantEntries(ILexEntry leOld, ILexEntry leNew)
 				m_mapIdGuid[id] = leNew.Guid;
 		}
 
+		private void MergeDialectLabels(ILexEntry leOld, ILexEntry leNew)
+		{
+			// We don't want duplicates, so we have to check each reference.
+			foreach (var dlOld in leOld.DialectLabelsRS)
+			{
+				if (!leNew.DialectLabelsRS.Contains(dlOld))
+					leNew.DialectLabelsRS.Add(dlOld);
+			}
+		}
+
 		/// Use the newest date between the two dates, as long as it is different from the importDate
 		private void MergeDates(ILexEntry leOld, ILexEntry leNew)
 		{

tests/SIL.LCModel.Tests/Application/ApplicationServices/XmlImportDataTests.cs

@@ -1415,6 +1415,40 @@ public void MergeCreatedDateWorks()
 					"The DateCreated of the entries should match the import data.");
 			}
 		}
+
+		[Test]
+		public void DialectLabelMergeWorks()
+		{
+			var xid = new XmlImportData(m_cache, false);
+			using(var reader = new StringReader("<LexDb xmlns:msxsl=\"urn:schemas-microsoft-com:xslt\" xmlns:user=\"urn:my-scripts\">" +
+												"<Entries><LexEntry><LexemeForm><MoStemAllomorph><MorphType><Link ws=\"en\" name=\"stem\" />" +
+												"</MorphType><Form><AUni ws=\"cub\">ãcʉriojomecacʉ</AUni></Form></MoStemAllomorph></LexemeForm>" +
+												"<DateCreated><Time val=\"2011-09-14 12:00:00.000\" /></DateCreated>" +
+												"<DialectLabels><Link ws=\"en\" abbr=\"C\" name=\"C\" /></DialectLabels><EntryRefs><LexEntryRef>" +
+												"<ComponentLexemes><Link ws=\"cub\" entry=\"ãcʉriojʉmecacʉ\" /></ComponentLexemes></LexEntryRef></EntryRefs>" +
+												"</LexEntry>" +
+												"<LexEntry id=\"IID0E3\"><LexemeForm><MoStemAllomorph><MorphType><Link ws=\"en\" name=\"stem\" /></MorphType>" +
+												"<Form><AUni ws=\"cub\">ãcʉriojʉmecacʉ</AUni></Form></MoStemAllomorph></LexemeForm>" +
+												"<DateCreated><Time val=\"2011-09-14 12:00:00.000\" /></DateCreated>" +
+												"<DialectLabels><Link ws=\"en\" abbr=\"Q\" name=\"Q\" /><Link ws=\"en\" abbr=\"V\" name=\"V\" /></DialectLabels>" +
+												"<MorphoSyntaxAnalyses><MoStemMsa id=\"MSA1000\"><PartOfSpeech><Link ws=\"en\" abbr=\"s.\" /></PartOfSpeech>" +
+												"</MoStemMsa></MorphoSyntaxAnalyses><Senses><LexSense><Definition><AStr ws=\"en\">" +
+												"<Run ws=\"en\">tree species cf jocʉcʉ</Run></AStr></Definition>" +
+												"<MorphoSyntaxAnalysis><Link target=\"MSA1000\" /></MorphoSyntaxAnalysis></LexSense></Senses></LexEntry>" +
+												"<LexEntry><LexemeForm><MoStemAllomorph><MorphType><Link ws=\"en\" name=\"stem\" /></MorphType>" +
+												"<Form><AUni ws=\"cub\">ãcʉriojomecacʉ</AUni></Form></MoStemAllomorph></LexemeForm>" +
+												"<EntryRefs><LexEntryRef><VariantEntryTypes><Link ws=\"es\" name=\"Variante\" /></VariantEntryTypes>" +
+												"<ComponentLexemes><Link target=\"IID0E3\" /></ComponentLexemes></LexEntryRef></EntryRefs></LexEntry>" +
+												"</Entries></LexDb>"))
+			using(var writer = new StringWriter(new StringBuilder()))
+			{
+				xid.ImportData(reader, writer, null);
+				var entries = m_cache.LangProject.LexDbOA.Entries.ToArray();
+				Assert.That(entries.Length, Is.EqualTo(2), "The lexicon should have 2 entries.");
+				Assert.That(entries[0].DialectLabelsRS.Count, Is.EqualTo(2));
+				Assert.That(entries[1].DialectLabelsRS.Count, Is.EqualTo(1));
+			}
+		}
 		///--------------------------------------------------------------------------------------
 		/// <summary>
 		/// Tests the method ImportData() on sequence lexical relations.