Add option for LSP-based auto insert

src/LanguageServer/Protocol/Handler/Configuration/DidChangeConfigurationNotificationHandler_OptionList.cs

@@ -54,6 +54,7 @@ internal partial class DidChangeConfigurationNotificationHandler
             SolutionCrawlerOptionsStorage.CompilerDiagnosticsScopeOption,
             LspOptionsStorage.LspEnableReferencesCodeLens,
             LspOptionsStorage.LspEnableTestsCodeLens,
+            LspOptionsStorage.LspEnableAutoInsert,
             LanguageServerProjectSystemOptionsStorage.BinaryLogPath,
             LanguageServerProjectSystemOptionsStorage.EnableAutomaticRestore,
             MetadataAsSourceOptionsStorage.NavigateToSourceLinkAndEmbeddedSources,

src/LanguageServer/Protocol/Handler/OnAutoInsert/OnAutoInsertHandler.cs

@@ -50,6 +50,10 @@ internal sealed class OnAutoInsertHandler(
             if (document == null)
                 return SpecializedTasks.Null<LSP.VSInternalDocumentOnAutoInsertResponseItem>();
 
+            var onAutoInsertEnabled = _globalOptions.GetOption(LspOptionsStorage.LspEnableAutoInsert, document.Project.Language);
+            if (!onAutoInsertEnabled)
+                return SpecializedTasks.Null<LSP.VSInternalDocumentOnAutoInsertResponseItem>();
+
             var servicesForDocument = _braceCompletionServices.Where(s => s.Metadata.Language == document.Project.Language).SelectAsArray(s => s.Value);
             var isRazorRequest = context.ServerKind == WellKnownLspServerKinds.RazorLspServer;
             var position = ProtocolConversions.PositionToLinePosition(request.Position);

src/LanguageServer/Protocol/LspOptionsStorage.cs

@@ -32,6 +32,8 @@ internal sealed class LspOptionsStorage
 
         private static readonly OptionGroup s_codeLensOptionGroup = new(name: "code_lens", description: "");
 
+        private static readonly OptionGroup s_autoInsertOptionGroup = new(name: "auto_insert", description: "");
+
         /// <summary>
         /// Flag indicating whether or not references should be returned in LSP codelens.
         /// </summary>
@@ -41,5 +43,10 @@ internal sealed class LspOptionsStorage
         /// Flag indicating whether or not test and debug code lens items should be returned.
         /// </summary>
         public static readonly PerLanguageOption2<bool> LspEnableTestsCodeLens = new("dotnet_enable_tests_code_lens", defaultValue: true, group: s_codeLensOptionGroup);
+
+        /// <summary>
+        /// Flag indicating whether or not auto-insert should be abled by default in LSP.
+        /// </summary>
+        public static readonly PerLanguageOption2<bool> LspEnableAutoInsert = new("dotnet_enable_auto_insert", defaultValue: true, group: s_autoInsertOptionGroup);
     }
 }

src/LanguageServer/ProtocolUnitTests/Configuration/DidChangeConfigurationNotificationHandlerTest.cs

@@ -144,6 +144,7 @@ public void VerifyLspClientOptionNames()
                 "background_analysis.dotnet_compiler_diagnostics_scope",
                 "code_lens.dotnet_enable_references_code_lens",
                 "code_lens.dotnet_enable_tests_code_lens",
+                "auto_insert.dotnet_enable_auto_insert",
                 "projects.dotnet_binary_log_path",
                 "projects.dotnet_enable_automatic_restore",
                 "navigation.dotnet_navigate_to_source_link_and_embedded_sources"

src/VisualStudio/Core/Test.Next/Options/VisualStudioOptionStorageTests.cs

@@ -230,6 +230,7 @@ public void OptionHasStorageIfNecessary(string configName)
             "dotnet_lsp_using_devkit",                                                      // VSCode internal only option.  Does not need any UI.
             "dotnet_enable_references_code_lens",                                           // VSCode only option.  Does not apply to VS.
             "dotnet_enable_tests_code_lens",                                                // VSCode only option.  Does not apply to VS.
+            "dotnet_enable_auto_insert",                                                    // VSCode only option.  Does not apply to VS.
             "end_of_line",                                                                  // persisted by the editor
             "ExtensionManagerOptions_DisableCrashingExtensions",                            // TODO: remove? https://github.com/dotnet/roslyn/issues/66063
             "FeatureOnOffOptions_RefactoringVerification",                                  // TODO: remove? https://github.com/dotnet/roslyn/issues/66063