Manually send didConfigurationChange on interpreter change (#12366)

Author: jakebailey

src/client/activation/node/languageServerProxy.ts

@@ -3,10 +3,16 @@
 import '../../common/extensions';
 
 import { inject, injectable } from 'inversify';
-import { Disposable, LanguageClient, LanguageClientOptions } from 'vscode-languageclient';
+import {
+    DidChangeConfigurationNotification,
+    Disposable,
+    LanguageClient,
+    LanguageClientOptions
+} from 'vscode-languageclient';
 
+import { DeprecatePythonPath } from '../../common/experiments/groups';
 import { traceDecorators, traceError } from '../../common/logger';
-import { IConfigurationService, Resource } from '../../common/types';
+import { IConfigurationService, IExperimentsManager, IInterpreterPathService, Resource } from '../../common/types';
 import { createDeferred, Deferred, sleep } from '../../common/utils/async';
 import { swallowExceptions } from '../../common/utils/decorators';
 import { noop } from '../../common/utils/misc';
@@ -32,7 +38,9 @@ export class NodeLanguageServerProxy implements ILanguageServerProxy {
         @inject(ILanguageClientFactory) private readonly factory: ILanguageClientFactory,
         @inject(ITestManagementService) private readonly testManager: ITestManagementService,
         @inject(IConfigurationService) private readonly configurationService: IConfigurationService,
-        @inject(ILanguageServerFolderService) private readonly folderService: ILanguageServerFolderService
+        @inject(ILanguageServerFolderService) private readonly folderService: ILanguageServerFolderService,
+        @inject(IExperimentsManager) private readonly experiments: IExperimentsManager,
+        @inject(IInterpreterPathService) private readonly interpreterPathService: IInterpreterPathService
     ) {
         this.startupCompleted = createDeferred<void>();
     }
@@ -95,6 +103,20 @@ export class NodeLanguageServerProxy implements ILanguageServerProxy {
             const progressReporting = new ProgressReporting(this.languageClient!);
             this.disposables.push(progressReporting);
 
+            if (this.experiments.inExperiment(DeprecatePythonPath.experiment)) {
+                this.disposables.push(
+                    this.interpreterPathService.onDidChange(() => {
+                        // Manually send didChangeConfiguration in order to get the server to requery
+                        // the workspace configurations (to then pick up pythonPath set in the middleware).
+                        // This is needed as interpreter changes via the interpreter path service happen
+                        // outside of VS Code's settings (which would mean VS Code sends the config updates itself).
+                        this.languageClient!.sendNotification(DidChangeConfigurationNotification.type, {
+                            settings: null
+                        });
+                    })
+                );
+            }
+
             const settings = this.configurationService.getSettings(resource);
             if (settings.downloadLanguageServer) {
                 this.languageClient.onTelemetry((telemetryEvent) => {