Merge pull request #3122 from rchande/stabilization

Port VB filtering changes (#3088)

src/EditorFeatures/Test2/IntelliSense/VisualBasicCompletionCommandHandlerTests.vb

@@ -2123,5 +2123,25 @@ Class C
                 state.AssertNoCompletionSession()
             End Using
         End Sub
+
+        <WorkItem(3088, "https://github.com/dotnet/roslyn/issues/3088")>
+        <Fact, Trait(Traits.Feature, Traits.Features.Completion)>
+        Public Sub DoNotPreferParameterNames()
+            Using state = TestState.CreateVisualBasicTestState(
+                <Document><![CDATA[
+Module Program
+    Sub Main(args As String())
+        Dim Table As Integer
+        foo(table$$)
+    End Sub
+
+    Sub foo(table As String)
+
+    End Sub
+End Module]]></Document>)
+                state.SendInvokeCompletionList()
+                state.AssertSelectedCompletionItem("Table")
+            End Using
+        End Sub
     End Class
 End Namespace

src/Features/Core/Completion/AbstractCompletionService.CompletionRules.cs

@@ -80,7 +80,7 @@ private bool IsAllDigits(string filterText)
 
                 if (match1 != null && match2 != null)
                 {
-                    var result = match1.Value.CompareTo(match2.Value);
+                    var result = CompareMatches(match1.Value, match2.Value, item1, item2);
                     if (result != 0)
                     {
                         return result < 0;
@@ -118,6 +118,11 @@ private bool IsAllDigits(string filterText)
                 return item1MRUIndex < item2MRUIndex;
             }
 
+            protected virtual int CompareMatches(PatternMatch match1, PatternMatch match2, CompletionItem item1, CompletionItem item2)
+            {
+                return match1.CompareTo(match2);
+            }
+
             public virtual bool? ShouldSoftSelectItem(CompletionItem item, string filterText, CompletionTriggerInfo triggerInfo)
             {
                 return filterText.Length == 0 && !item.Preselect;

src/Features/Core/Shared/Utilities/PatternMatch.cs

@@ -51,7 +51,7 @@ public int CompareTo(PatternMatch other)
             return 0;
         }
 
-        private int ComparePunctuation(PatternMatch result1, PatternMatch result2)
+        internal static int ComparePunctuation(PatternMatch result1, PatternMatch result2)
         {
             // Consider a match to be better if it was successful without stripping punctuation
             // versus a match that had to strip punctuation to succeed.
@@ -63,7 +63,7 @@ private int ComparePunctuation(PatternMatch result1, PatternMatch result2)
             return 0;
         }
 
-        private static int CompareCase(PatternMatch result1, PatternMatch result2)
+        internal static int CompareCase(PatternMatch result1, PatternMatch result2)
         {
             if (result1.IsCaseSensitive != result2.IsCaseSensitive)
             {
@@ -73,12 +73,12 @@ private static int CompareCase(PatternMatch result1, PatternMatch result2)
             return 0;
         }
 
-        private static int CompareType(PatternMatch result1, PatternMatch result2)
+        internal static int CompareType(PatternMatch result1, PatternMatch result2)
         {
             return result1.Kind - result2.Kind;
         }
 
-        private static int CompareCamelCase(PatternMatch result1, PatternMatch result2)
+        internal static int CompareCamelCase(PatternMatch result1, PatternMatch result2)
         {
             if (result1.Kind == PatternMatchKind.CamelCase && result2.Kind == PatternMatchKind.CamelCase)
             {

src/Features/VisualBasic/Completion/VisualBasicCompletionRules.vb

@@ -14,6 +14,41 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Completion
                 MyBase.New(service)
             End Sub
 
+            Protected Overrides Function CompareMatches(leftMatch As PatternMatch, rightMatch As PatternMatch, leftItem As CompletionItem, rightItem As CompletionItem) As Integer
+                Dim diff As Integer
+                diff = PatternMatch.CompareType(leftMatch, rightMatch)
+                If diff <> 0 Then
+                    Return diff
+                End If
+
+                diff = PatternMatch.CompareCamelCase(leftMatch, rightMatch)
+                If diff <> 0 Then
+                    Return diff
+                End If
+
+                ' More important than the case sensitivity is that "left" isn't an argument name
+                Dim leftIsNamedArgument = TypeOf leftItem.CompletionProvider Is NamedParameterCompletionProvider
+                Dim rightIsNamedArgument = TypeOf rightItem.CompletionProvider Is NamedParameterCompletionProvider
+                If leftIsNamedArgument AndAlso Not rightIsNamedArgument Then
+                    Return 1
+                End If
+                If rightIsNamedArgument AndAlso Not leftIsNamedArgument Then
+                    Return -1
+                End If
+
+                diff = PatternMatch.CompareCase(leftMatch, rightMatch)
+                If diff <> 0 Then
+                    Return diff
+                End If
+
+                diff = PatternMatch.ComparePunctuation(leftMatch, rightMatch)
+                If diff <> 0 Then
+                    Return diff
+                End If
+
+                Return 0
+            End Function
+
             Public Overrides Function IsBetterFilterMatch(item1 As CompletionItem, item2 As CompletionItem, filterText As String, triggerInfo As CompletionTriggerInfo, filterReason As CompletionFilterReason) As Boolean?
                 If filterReason = CompletionFilterReason.BackspaceOrDelete Then
                     Dim prefixLength1 = GetPrefixLength(item1.FilterText, filterText)