Bugfix: initial bottom counts can throw error when a book was moved since Libation was last run

DataLayer/UNTESTED/LibationContext.cs

@@ -64,7 +64,8 @@ namespace DataLayer
 				.Entity<Contributor>()
 				.HasData(Contributor.GetEmpty());
 
-            // views are now supported via "query types" (instead of "entity types"): https://docs.microsoft.com/en-us/ef/core/modeling/query-types
-        }
-    }
+			// views are now supported via "keyless entity types" (instead of "entity types" or the prev "query types"):
+			// https://docs.microsoft.com/en-us/ef/core/modeling/keyless-entity-types
+		}
+	}
 }

DataLayer/UNTESTED/TagPersistenceInterceptor.cs

@@ -4,7 +4,6 @@ using System.Linq;
 using Dinah.Core.Collections.Generic;
 using Dinah.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore;
-using Microsoft.EntityFrameworkCore.ChangeTracking;
 
 namespace DataLayer
 {
@@ -14,24 +13,17 @@ namespace DataLayer
 
         public void Executing(DbContext context)
 		{
-			// persist tags:
-			var modifiedEntities = context
+			var tagsCollection
+				= context
 				.ChangeTracker
 				.Entries()
-				.Where(p => p.State.In(EntityState.Modified, EntityState.Added))
-				.ToList();
-
-			persistTags(modifiedEntities);
-		}
-
-		private static void persistTags(List<EntityEntry> modifiedEntities)
-		{
-			var tagsCollection = modifiedEntities
+				.Where(e => e.State.In(EntityState.Modified, EntityState.Added))
 				.Select(e => e.Entity as UserDefinedItem)
-				// filter by null but NOT by blank. blank is the valid way to show the absence of tags
-				.Where(a => a != null)
+				.Where(udi => udi != null)
+				// do NOT filter out entires with blank tags. blank is the valid way to show the absence of tags
 				.Select(t => (t.Book.AudibleProductId, t.Tags))
 				.ToList();
+
 			FileManager.TagsPersistence.Save(tagsCollection);
 		}
 	}