Use immutable sets in Navigate To abstraction

src/EditorFeatures/Core.Wpf/NavigateTo/NavigateToItemProvider.Searcher.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System;
-using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Linq;
 using System.Threading;
@@ -26,7 +25,7 @@ private class Searcher
             private readonly INavigateToCallback _callback;
             private readonly string _searchPattern;
             private readonly bool _searchCurrentDocument;
-            private readonly ISet<string> _kinds;
+            private readonly IImmutableSet<string> _kinds;
             private readonly Document _currentDocument;
             private readonly ProgressTracker _progress;
             private readonly IAsynchronousOperationListener _asyncListener;
@@ -39,7 +38,7 @@ private class Searcher
                 INavigateToCallback callback,
                 string searchPattern,
                 bool searchCurrentDocument,
-                ISet<string> kinds,
+                IImmutableSet<string> kinds,
                 CancellationToken cancellationToken)
             {
                 _solution = solution;
@@ -215,14 +214,14 @@ public ShimNavigateToSearchService(INavigateToSearchService navigateToSearchServ
                     _navigateToSearchService = navigateToSearchService;
                 }
 
-                public IImmutableSet<string> KindsProvided => ImmutableHashSet<string>.Empty;
+                public IImmutableSet<string> KindsProvided => ImmutableHashSet.Create<string>(StringComparer.Ordinal);
 
                 public bool CanFilter => false;
 
-                public Task<ImmutableArray<INavigateToSearchResult>> SearchDocumentAsync(Document document, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken)
+                public Task<ImmutableArray<INavigateToSearchResult>> SearchDocumentAsync(Document document, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
                     => _navigateToSearchService.SearchDocumentAsync(document, searchPattern, cancellationToken);
 
-                public Task<ImmutableArray<INavigateToSearchResult>> SearchProjectAsync(Project project, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken)
+                public Task<ImmutableArray<INavigateToSearchResult>> SearchProjectAsync(Project project, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
                     => _navigateToSearchService.SearchProjectAsync(project, searchPattern, cancellationToken);
             }
         }

src/EditorFeatures/Core.Wpf/NavigateTo/NavigateToItemProvider.cs

@@ -2,6 +2,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Threading;
 using Microsoft.CodeAnalysis.Shared.TestHooks;
 using Microsoft.VisualStudio.Language.NavigateTo.Interfaces;
@@ -31,17 +32,19 @@ internal partial class NavigateToItemProvider : INavigateToItemProvider2
             _displayFactory = new NavigateToItemDisplayFactory();
         }
 
-        public ISet<string> KindsProvided
+        ISet<string> INavigateToItemProvider2.KindsProvided => KindsProvided;
+
+        public ImmutableHashSet<string> KindsProvided
         {
             get
             {
-                var result = new HashSet<string>(StringComparer.Ordinal);
+                var result = ImmutableHashSet.Create<string>(StringComparer.Ordinal);
                 foreach (var project in _workspace.CurrentSolution.Projects)
                 {
                     var navigateToSearchService = project.LanguageServices.GetService<INavigateToSearchService_RemoveInterfaceAboveAndRenameThisAfterInternalsVisibleToUsersUpdate>();
                     if (navigateToSearchService != null)
                     {
-                        result.UnionWith(navigateToSearchService.KindsProvided);
+                        result = result.Union(navigateToSearchService.KindsProvided);
                         continue;
                     }
                 }
@@ -125,10 +128,10 @@ private bool GetSearchCurrentDocumentOptionWorker(INavigateToCallback callback)
 
         public void StartSearch(INavigateToCallback callback, string searchValue, INavigateToFilterParameters filter)
         {
-            StartSearch(callback, searchValue, filter.Kinds);
+            StartSearch(callback, searchValue, filter.Kinds.ToImmutableHashSet(StringComparer.Ordinal));
         }
 
-        private void StartSearch(INavigateToCallback callback, string searchValue, ISet<string> kinds)
+        private void StartSearch(INavigateToCallback callback, string searchValue, IImmutableSet<string> kinds)
         {
             this.StopSearch();
 

src/Features/Core/Portable/NavigateTo/AbstractNavigateToSearchService.InProcess.cs

@@ -23,21 +23,21 @@ internal abstract partial class AbstractNavigateToSearchService
             new ConditionalWeakTable<Project, Tuple<string, ImmutableArray<SearchResult>>>();
 
         public static Task<ImmutableArray<INavigateToSearchResult>> SearchProjectInCurrentProcessAsync(
-            Project project, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken)
+            Project project, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
         {
             return FindSearchResultsAsync(
                 project, searchDocument: null, pattern: searchPattern, kinds, cancellationToken: cancellationToken);
         }
 
         public static Task<ImmutableArray<INavigateToSearchResult>> SearchDocumentInCurrentProcessAsync(
-            Document document, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken)
+            Document document, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
         {
             return FindSearchResultsAsync(
                 document.Project, document, searchPattern, kinds, cancellationToken);
         }
 
         private static async Task<ImmutableArray<INavigateToSearchResult>> FindSearchResultsAsync(
-            Project project, Document searchDocument, string pattern, ISet<string> kinds, CancellationToken cancellationToken)
+            Project project, Document searchDocument, string pattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
         {
             // If the user created a dotted pattern then we'll grab the last part of the name
             var (patternName, patternContainerOpt) = PatternMatcher.GetNameAndContainer(pattern);

src/Features/Core/Portable/NavigateTo/AbstractNavigateToSearchService.Remote.cs

@@ -2,6 +2,7 @@
 
 using System.Collections.Generic;
 using System.Collections.Immutable;
+using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.Remote;
@@ -12,25 +13,25 @@ namespace Microsoft.CodeAnalysis.NavigateTo
     internal abstract partial class AbstractNavigateToSearchService
     {
         private async Task<ImmutableArray<INavigateToSearchResult>> SearchDocumentInRemoteProcessAsync(
-            RemoteHostClient client, Document document, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken)
+            RemoteHostClient client, Document document, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
         {
             var solution = document.Project.Solution;
 
             var serializableResults = await client.TryRunCodeAnalysisRemoteAsync<IList<SerializableNavigateToSearchResult>>(
                 solution, nameof(IRemoteNavigateToSearchService.SearchDocumentAsync),
-                new object[] { document.Id, searchPattern, kinds }, cancellationToken).ConfigureAwait(false);
+                new object[] { document.Id, searchPattern, kinds.ToArray() }, cancellationToken).ConfigureAwait(false);
 
             return serializableResults.SelectAsArray(r => r.Rehydrate(solution));
         }
 
         private async Task<ImmutableArray<INavigateToSearchResult>> SearchProjectInRemoteProcessAsync(
-            RemoteHostClient client, Project project, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken)
+            RemoteHostClient client, Project project, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
         {
             var solution = project.Solution;
 
             var serializableResults = await client.TryRunCodeAnalysisRemoteAsync<IList<SerializableNavigateToSearchResult>>(
                 solution, nameof(IRemoteNavigateToSearchService.SearchProjectAsync),
-                new object[] { project.Id, searchPattern, kinds }, cancellationToken).ConfigureAwait(false);
+                new object[] { project.Id, searchPattern, kinds.ToArray() }, cancellationToken).ConfigureAwait(false);
 
             return serializableResults.SelectAsArray(r => r.Rehydrate(solution));
         }

src/Features/Core/Portable/NavigateTo/AbstractNavigateToSearchService.cs

@@ -26,7 +26,7 @@ internal abstract partial class AbstractNavigateToSearchService : INavigateToSea
         public bool CanFilter => true;
 
         public async Task<ImmutableArray<INavigateToSearchResult>> SearchDocumentAsync(
-            Document document, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken)
+            Document document, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
         {
             var client = await TryGetRemoteHostClientAsync(document.Project, cancellationToken).ConfigureAwait(false);
             if (client == null)
@@ -42,7 +42,7 @@ internal abstract partial class AbstractNavigateToSearchService : INavigateToSea
         }
 
         public async Task<ImmutableArray<INavigateToSearchResult>> SearchProjectAsync(
-            Project project, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken)
+            Project project, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken)
         {
             var client = await TryGetRemoteHostClientAsync(project, cancellationToken).ConfigureAwait(false);
             if (client == null)

src/Features/Core/Portable/NavigateTo/INavigateToSearchService.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System;
-using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Threading;
 using System.Threading.Tasks;
@@ -28,7 +27,7 @@ bool CanFilter
             get;
         }
 
-        Task<ImmutableArray<INavigateToSearchResult>> SearchProjectAsync(Project project, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken);
-        Task<ImmutableArray<INavigateToSearchResult>> SearchDocumentAsync(Document document, string searchPattern, ISet<string> kinds, CancellationToken cancellationToken);
+        Task<ImmutableArray<INavigateToSearchResult>> SearchProjectAsync(Project project, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken);
+        Task<ImmutableArray<INavigateToSearchResult>> SearchDocumentAsync(Document document, string searchPattern, IImmutableSet<string> kinds, CancellationToken cancellationToken);
     }
 }