Fix serialization of capabilities in onautoinsert

src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer.UnitTests/ServerInitializationTests.cs

@@ -3,6 +3,7 @@
 // See the LICENSE file in the project root for more information.
 
 using Roslyn.LanguageServer.Protocol;
+using Roslyn.Test.Utilities;
 using Xunit.Abstractions;
 
 namespace Microsoft.CodeAnalysis.LanguageServer.UnitTests;
@@ -54,4 +55,15 @@ public async Task TestServerHandlesTextSyncRequestsAsync()
         // These are notifications so we should get a null response (but no exceptions).
         Assert.Null(response);
     }
+
+    [Fact]
+    public async Task TestOnAutoInsertCapabilitiesSerializedCorrectly()
+    {
+        await using var server = await CreateLanguageServerAsync();
+
+        var capabilities = server.ServerCapabilities as VSInternalServerCapabilities;
+        AssertEx.NotNull(capabilities);
+        AssertEx.NotNull(capabilities.OnAutoInsertProvider);
+        Assert.NotEmpty(capabilities.OnAutoInsertProvider.TriggerCharacters);
+    }
 }

src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer.UnitTests/Utilities/AbstractLanguageServerHostTests.cs

@@ -30,13 +30,16 @@ protected sealed class TestLspServer : IAsyncDisposable
         private readonly Task _languageServerHostCompletionTask;
         private readonly JsonRpc _clientRpc;
 
+        private ServerCapabilities? _serverCapabilities;
+
         internal static async Task<TestLspServer> CreateAsync(ClientCapabilities clientCapabilities, TestOutputLogger logger, bool includeDevKitComponents = true)
         {
             var exportProvider = await LanguageServerTestComposition.CreateExportProviderAsync(
                 logger.Factory, includeDevKitComponents, out var _, out var assemblyLoader);
             var testLspServer = new TestLspServer(exportProvider, logger, assemblyLoader);
             var initializeResponse = await testLspServer.ExecuteRequestAsync<InitializeParams, InitializeResult>(Methods.InitializeName, new InitializeParams { Capabilities = clientCapabilities }, CancellationToken.None);
             Assert.NotNull(initializeResponse?.Capabilities);
+            testLspServer._serverCapabilities = initializeResponse!.Capabilities;
 
             await testLspServer.ExecuteRequestAsync<InitializedParams, object>(Methods.InitializedName, new InitializedParams(), CancellationToken.None);
 
@@ -46,14 +49,16 @@ internal static async Task<TestLspServer> CreateAsync(ClientCapabilities clientC
         internal LanguageServerHost LanguageServerHost { get; }
         public ExportProvider ExportProvider { get; }
 
+        internal ServerCapabilities ServerCapabilities => _serverCapabilities ?? throw new InvalidOperationException("Initialize has not been called");
+
         private TestLspServer(ExportProvider exportProvider, TestOutputLogger logger, IAssemblyLoader assemblyLoader)
         {
             var typeRefResolver = new ExtensionTypeRefResolver(assemblyLoader, logger.Factory);
 
             var (clientStream, serverStream) = FullDuplexStream.CreatePair();
             LanguageServerHost = new LanguageServerHost(serverStream, serverStream, exportProvider, logger, typeRefResolver);
 
-            var messageFormatter = LanguageServerHost.CreateJsonMessageFormatter();
+            var messageFormatter = RoslynLanguageServer.CreateJsonMessageFormatter();
             _clientRpc = new JsonRpc(new HeaderDelimitedMessageHandler(clientStream, clientStream, messageFormatter))
             {
                 AllowModificationWhileListening = true,

src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/LanguageServer/LanguageServerHost.cs

@@ -29,7 +29,7 @@ internal sealed class LanguageServerHost
 
     public LanguageServerHost(Stream inputStream, Stream outputStream, ExportProvider exportProvider, ILogger logger, AbstractTypeRefResolver typeRefResolver)
     {
-        var messageFormatter = CreateJsonMessageFormatter();
+        var messageFormatter = RoslynLanguageServer.CreateJsonMessageFormatter();
 
         var handler = new HeaderDelimitedMessageHandler(outputStream, inputStream, messageFormatter);
 
@@ -56,14 +56,6 @@ public LanguageServerHost(Stream inputStream, Stream outputStream, ExportProvide
             typeRefResolver);
     }
 
-    internal static SystemTextJsonFormatter CreateJsonMessageFormatter()
-    {
-        var messageFormatter = new SystemTextJsonFormatter();
-        messageFormatter.JsonSerializerOptions.AddVSCodeInternalExtensionConverters();
-        messageFormatter.JsonSerializerOptions.Converters.Add(new NaturalObjectConverter());
-        return messageFormatter;
-    }
-
     public void Start()
     {
         _jsonRpc.StartListening();

src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework.UnitTests/TestExampleLanguageServer.cs

@@ -7,6 +7,7 @@
 using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.LanguageServer;
 using Microsoft.CommonLanguageServerProtocol.Framework.Example;
 using Microsoft.Extensions.DependencyInjection;
 using Nerdbank.Streams;
@@ -105,7 +106,7 @@ internal async Task<int> WaitForExit()
     private static SystemTextJsonFormatter CreateJsonMessageFormatter()
     {
         var messageFormatter = new SystemTextJsonFormatter();
-        messageFormatter.JsonSerializerOptions.AddVSCodeInternalExtensionConverters();
+        messageFormatter.JsonSerializerOptions.AddLspSerializerOptions();
         return messageFormatter;
     }