Merge pull request #12852 from rchande/fixColonCommit

Commit C# completion on colon

src/EditorFeatures/CSharpTest/Completion/CompletionProviders/NamedParameterCompletionProviderTests.cs

@@ -456,5 +456,55 @@ static void Main()
 ";
             await VerifyNoItemsExistAsync(markup);
         }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task CommitWithColonWordFullyTyped()
+        {
+            var markup = @"
+class Program
+{
+    static void Main(string[] args)
+    {
+        Main(args$$)
+    }
+}
+";
+
+            var expected = @"
+class Program
+{
+    static void Main(string[] args)
+    {
+        Main(args:)
+    }
+}
+";
+            await VerifyProviderCommitAsync(markup, "args:", expected, ':', "args");
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task CommitWithColonWordPartiallyTyped()
+        {
+            var markup = @"
+class Program
+{
+    static void Main(string[] args)
+    {
+        Main(ar$$)
+    }
+}
+";
+
+            var expected = @"
+class Program
+{
+    static void Main(string[] args)
+    {
+        Main(args:)
+    }
+}
+";
+            await VerifyProviderCommitAsync(markup, "args:", expected, ':', "arg");
+        }
     }
 }

src/EditorFeatures/Test2/IntelliSense/CSharpCompletionCommandHandlerTests.vb

@@ -1929,5 +1929,26 @@ class Program
                 Await state.AssertSelectedCompletionItem("Add", description:="void List<T>.Add(T item)")
             End Using
         End Function
+
+        <WpfFact, Trait(Traits.Feature, Traits.Features.Completion)>
+        Public Async Function TestCommitNamedParameterWithColon() As Task
+            Using state = TestState.CreateCSharpTestState(
+                           <Document><![CDATA[
+using System.Collections.Generic;
+
+class Program
+{
+    static void Main(int args)
+    {
+        Main(args$$
+    }
+}]]></Document>, extraExportedTypes:={GetType(CSharpEditorFormattingService)}.ToList())
+
+                state.SendInvokeCompletionList()
+                state.SendTypeChars(":")
+                Await state.AssertNoCompletionSession()
+                Assert.Contains("args:", state.GetLineTextFromCaretPosition())
+            End Using
+        End Function
     End Class
 End Namespace
\ No newline at end of file

src/Features/CSharp/Portable/Completion/CompletionProviders/NamedParameterCompletionProvider.cs

@@ -23,6 +23,11 @@ internal partial class NamedParameterCompletionProvider : CommonCompletionProvid
     {
         private const string ColonString = ":";
 
+        // Explicitly remove ":" from the set of filter characters because (by default)
+        // any character that appears in DisplayText gets treated as a filter char.
+        private static readonly CompletionItemRules s_rules = CompletionItemRules.Default
+            .WithFilterCharacterRule(CharacterSetModificationRule.Create(CharacterSetModificationKind.Remove, ':'));
+
         internal override bool IsInsertionTrigger(SourceText text, int characterPosition, OptionSet options)
         {
             return CompletionUtilities.IsTriggerCharacter(text, characterPosition, options);
@@ -96,7 +101,7 @@ public override async Task ProvideCompletionsAsync(CompletionContext context)
                     symbol: parameter,
                     contextPosition: token.SpanStart,
                     filterText: escapedName,
-                    rules: CompletionItemRules.Default,
+                    rules: s_rules,
                     matchPriority: SymbolMatchPriority.PreferNamedArgument));
             }
         }