Add temporary option to allow suppression of recoverable LSP error toasts

Author: dibarbet

package.json

@@ -1666,6 +1666,11 @@
             "default": null,
             "description": "%configuration.dotnet.server.crashDumpPath%"
           },
+          "dotnet.server.suppressLspErrorToasts": {
+            "type": "boolean",
+            "default": false,
+            "description": "%configuration.dotnet.server.suppressLspErrorToasts%"
+          },
           "dotnet.projects.binaryLogPath": {
             "scope": "machine-overridable",
             "type": "string",

package.nls.json

@@ -31,6 +31,7 @@
   "configuration.dotnet.server.trace": "Sets the logging level for the language server",
   "configuration.dotnet.server.extensionPaths": "Override for path to language server --extension arguments",
   "configuration.dotnet.server.crashDumpPath": "Sets a folder path where crash dumps are written to if the language server crashes.  Must be writeable by the user.",
+  "configuration.dotnet.server.suppressLspErrorToasts": "Suppresses error toasts from showing up if the server encounters a recoverable error.",
   "configuration.dotnet.projects.enableAutomaticRestore": "Enables automatic NuGet restore if the extension detects assets are missing.",
   "configuration.dotnet.preferCSharpExtension": "Forces projects to load with the C# extension only.  This can be useful when using legacy project types that are not supported by C# Dev Kit. (Requires window reload)",
   "configuration.dotnet.implementType.insertionBehavior": "The insertion location of properties, events, and methods When implement interface or abstract class.",

src/lsptoolshost/roslynLanguageClient.ts

@@ -3,9 +3,16 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import { LanguageClient, LanguageClientOptions, ServerOptions } from 'vscode-languageclient/node';
+import {
+    CancellationToken,
+    LanguageClient,
+    LanguageClientOptions,
+    MessageSignature,
+    ServerOptions,
+} from 'vscode-languageclient/node';
 import CompositeDisposable from '../compositeDisposable';
 import { IDisposable } from '../disposable';
+import { languageServerOptions } from '../shared/options';
 
 /**
  * Implementation of the base LanguageClient type that allows for additional items to be disposed of
@@ -14,6 +21,8 @@ import { IDisposable } from '../disposable';
 export class RoslynLanguageClient extends LanguageClient {
     private readonly _disposables: CompositeDisposable;
 
+    //private readonly Map<
+
     constructor(
         id: string,
         name: string,
@@ -31,6 +40,27 @@ export class RoslynLanguageClient extends LanguageClient {
         return super.dispose(timeout);
     }
 
+    override handleFailedRequest<T>(
+        type: MessageSignature,
+        token: CancellationToken | undefined,
+        error: any,
+        defaultValue: T,
+        showNotification?: boolean
+    ) {
+        // Temporarily allow LSP error toasts to be suppressed if configured.
+        // There are a few architectural issues preventing us from solving some of the underlying problems,
+        // for example Razor cohosting to fix text mismatch issues and unification of serialization libraries
+        // to fix URI identification issues.  Once resolved, we should remove this option.
+        //
+        // See also https://github.com/microsoft/vscode-dotnettools/issues/722
+        // https://github.com/dotnet/vscode-csharp/issues/6973
+        // https://github.com/microsoft/vscode-languageserver-node/issues/1449
+        if (languageServerOptions.suppressLspErrorToasts) {
+            return super.handleFailedRequest(type, token, error, defaultValue, false);
+        }
+        return super.handleFailedRequest(type, token, error, defaultValue, showNotification);
+    }
+
     /**
      * Adds a disposable that should be disposed of when the LanguageClient instance gets disposed.
      */

src/shared/options.ts

@@ -77,6 +77,7 @@ export interface LanguageServerOptions {
     readonly crashDumpPath: string | undefined;
     readonly analyzerDiagnosticScope: string;
     readonly compilerDiagnosticScope: string;
+    readonly suppressLspErrorToasts: boolean;
 }
 
 export interface RazorOptions {
@@ -397,6 +398,9 @@ class LanguageServerOptionsImpl implements LanguageServerOptions {
     public get compilerDiagnosticScope() {
         return readOption<string>('dotnet.backgroundAnalysis.compilerDiagnosticsScope', 'openFiles');
     }
+    public get suppressLspErrorToasts() {
+        return readOption<boolean>('dotnet.server.suppressLspErrorToasts', false);
+    }
 }
 
 class RazorOptionsImpl implements RazorOptions {