Set both completion options to ensure neither can cause unimported types to be included.

src/Features/LanguageServer/Protocol/Handler/Completion/CompletionHandler.cs

@@ -40,8 +40,11 @@ internal class CompletionHandler : IRequestHandler<LSP.CompletionParams, object>
             //     https://dev.azure.com/devdiv/DevDiv/_workitems/edit/1076759
             // 2.  We need to figure out how to provide the text edits along with the completion item or provide them in the resolve request.
             //     https://devdiv.visualstudio.com/DevDiv/_workitems/edit/985860/
+            // 3.  LSP client should support completion filters / expanders
             var documentOptions = await document.GetOptionsAsync(cancellationToken).ConfigureAwait(false);
-            var completionOptions = documentOptions.WithChangedOption(CompletionServiceOptions.IsExpandedCompletion, false);
+            var completionOptions = documentOptions
+                .WithChangedOption(CompletionOptions.ShowItemsFromUnimportedNamespaces, false)
+                .WithChangedOption(CompletionServiceOptions.IsExpandedCompletion, false);
 
             var completionService = document.Project.LanguageServices.GetService<CompletionService>();
             var list = await completionService.GetCompletionsAsync(document, position, options: completionOptions, cancellationToken: cancellationToken).ConfigureAwait(false);

src/Features/LanguageServer/ProtocolUnitTests/Completion/CompletionTests.cs

@@ -47,7 +47,9 @@ void M()
             var (solution, locations) = CreateTestSolution(markup);
 
             // Make sure the unimported types option is on by default.
-            solution = solution.WithOptions(solution.Options.WithChangedOption(CompletionServiceOptions.IsExpandedCompletion, true));
+            solution = solution.WithOptions(solution.Options
+                .WithChangedOption(CompletionOptions.ShowItemsFromUnimportedNamespaces, LanguageNames.CSharp, true)
+                .WithChangedOption(CompletionServiceOptions.IsExpandedCompletion, true));
 
             var expected = CreateCompletionItem("A", LSP.CompletionItemKind.Class, new string[] { "Class", "Internal" }, CreateCompletionParams(locations["caret"].Single()));
             var clientCapabilities = new LSP.VSClientCapabilities { SupportsVisualStudioExtensions = true };