Ensure we handle errors when checking support for LS (microsoft#3620)

DonJayamanne · web-flow · commit aec70d051755 · 2018-12-10T23:05:47.000-08:00
For microsoft#2729
diff --git a/src/client/activation/languageServer/languageServerCompatibilityService.ts b/src/client/activation/languageServer/languageServerCompatibilityService.ts
@@ -5,6 +5,7 @@
 
 import { inject, injectable } from 'inversify';
 import { IDotNetCompatibilityService } from '../../common/dotnet/types';
+import { traceError } from '../../common/logger';
 import { sendTelemetryEvent } from '../../telemetry';
 import { PYTHON_LANGUAGE_SERVER_PLATFORM_SUPPORTED } from '../../telemetry/constants';
 import { ILanguageServerCompatibilityService } from '../types';
@@ -13,8 +14,14 @@ import { ILanguageServerCompatibilityService } from '../types';
 export class LanguageServerCompatibilityService implements ILanguageServerCompatibilityService {
     constructor(@inject(IDotNetCompatibilityService) private readonly dotnetCompatibility: IDotNetCompatibilityService) { }
     public async isSupported(): Promise<boolean> {
-        const supported = await this.dotnetCompatibility.isSupported();
-        sendTelemetryEvent(PYTHON_LANGUAGE_SERVER_PLATFORM_SUPPORTED, undefined, { supported });
-        return supported;
+        try {
+            const supported = await this.dotnetCompatibility.isSupported();
+            sendTelemetryEvent(PYTHON_LANGUAGE_SERVER_PLATFORM_SUPPORTED, undefined, { supported });
+            return supported;
+        } catch (ex) {
+            traceError('Unable to determine whether LS is supported', ex);
+            sendTelemetryEvent(PYTHON_LANGUAGE_SERVER_PLATFORM_SUPPORTED, undefined, { supported: false, failureType: 'UnknownError' });
+            return false;
+        }
     }
 }
diff --git a/src/client/telemetry/types.ts b/src/client/telemetry/types.ts
@@ -29,6 +29,7 @@ export type LanguageServerErrorTelemetry = {
 
 export type LanguageServePlatformSupported = {
     supported: boolean;
+    failureType?: 'UnknownError';
 };
 
 export type LinterTrigger = 'auto' | 'save';
diff --git a/src/test/activation/languageServer/languageServerCompatibilityService.unit.test.ts b/src/test/activation/languageServer/languageServerCompatibilityService.unit.test.ts
@@ -0,0 +1,34 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+'use strict';
+
+import { expect } from 'chai';
+import * as typeMoq from 'typemoq';
+import { LanguageServerCompatibilityService } from '../../../client/activation/languageServer/languageServerCompatibilityService';
+import { ILanguageServerCompatibilityService } from '../../../client/activation/types';
+import { IDotNetCompatibilityService } from '../../../client/common/dotnet/types';
+
+suite('Language Server Support', () => {
+    let compatService: typeMoq.IMock<IDotNetCompatibilityService>;
+    let service: ILanguageServerCompatibilityService;
+    setup(() => {
+        compatService = typeMoq.Mock.ofType<IDotNetCompatibilityService>();
+        service = new LanguageServerCompatibilityService(compatService.object);
+    });
+    test('Not supported if there are errors ', async () => {
+        compatService.setup(c => c.isSupported()).returns(() => Promise.reject(new Error('kaboom')));
+        const supported = await service.isSupported();
+        expect(supported).to.equal(false, 'incorrect');
+    });
+    test('Not supported if there are not errors ', async () => {
+        compatService.setup(c => c.isSupported()).returns(() => Promise.resolve(false));
+        const supported = await service.isSupported();
+        expect(supported).to.equal(false, 'incorrect');
+    });
+    test('Support if there are not errors ', async () => {
+        compatService.setup(c => c.isSupported()).returns(() => Promise.resolve(true));
+        const supported = await service.isSupported();
+        expect(supported).to.equal(true, 'incorrect');
+    });
+});
