prefer intellicode items

src/EditorFeatures/Core/Implementation/IntelliSense/AsyncCompletion/ItemManager.cs

@@ -293,12 +293,12 @@ private static bool IsAfterDot(ITextSnapshot snapshot, ITrackingSpan applicableT
             if (bestItem != null)
             {
                 selectedItemIndex = itemsInList.IndexOf(i => Equals(i.FilterResult.CompletionItem, bestItem));
-                var deduplicatedList = matchingItems.Where(r => !r.IsPreferredItem());
+                var deduplicatedListCount = matchingItems.Where(r => !r.IsPreferredItem()).Count();
                 if (selectedItemIndex > -1 &&
-                    deduplicatedList.Count() == 1 &&
+                    deduplicatedListCount == 1 &&
                     filterText.Length > 0)
                 {
-                    var uniqueItemIndex = itemsInList.IndexOf(i => Equals(i.FilterResult.CompletionItem, deduplicatedList.First()));
+                    var uniqueItemIndex = itemsInList.IndexOf(i => Equals(i.FilterResult.CompletionItem, bestItem));
                     uniqueItem = highlightedList[uniqueItemIndex].CompletionItem;
                 }
             }
@@ -514,7 +514,7 @@ private static bool ShouldBeFilteredOutOfCompletionList(VSCompletionItem item, I
                 var bestItemPriority = bestItem.Rules.MatchPriority;
                 var currentItemPriority = chosenItem.Rules.MatchPriority;
 
-                if ((currentItemPriority > bestItemPriority) || 
+                if ((currentItemPriority > bestItemPriority) ||
                     ((currentItemPriority == bestItemPriority) && !bestItem.IsPreferredItem() && chosenItem.IsPreferredItem()))
                 {
                     bestItem = chosenItem;

src/EditorFeatures/Test2/IntelliSense/CSharpCompletionCommandHandlerTests.vb

@@ -5477,7 +5477,7 @@ class C
         ' We want to ignore these items in CommitIfUnique.
         ' This situation should not happen. Tests with this provider were added to cover protective scenarios.
         Private Class IntelliCodeMockWeirdProvider
-            Inherits CompletionProvider
+            Inherits IntelliCodeMockProvider
 
             Public Overrides Function ProvideCompletionsAsync(context As CompletionContext) As Task
                 context.AddItem(CompletionItem.Create(displayText:="★ Length2", filterText:="Length2"))
@@ -5485,10 +5485,6 @@ class C
                 context.AddItem(CompletionItem.Create(displayText:="★ Length3", filterText:="Length3"))
                 Return Task.CompletedTask
             End Function
-
-            Public Overrides Function ShouldTriggerCompletion(text As SourceText, caretPosition As Integer, trigger As CompletionTrigger, options As OptionSet) As Boolean
-                Return True
-            End Function
         End Class
     End Class
 End Namespace