Use adaptive debounce when resolving code lenses

package.json

@@ -72,9 +72,9 @@
         },
         "viewsWelcome": [
             {
-              "view": "testExplorer",
-              "contents": "No test cases are listed because the Java Language Server is currently running in [LightWeight Mode](https://aka.ms/vscode-java-lightweight). To show test cases, click on the button to switch to Standard Mode.\n[Switch to Standard Mode](command:java.server.mode.switch?%5B%22Standard%22,true%5D)",
-              "when": "java:serverMode == LightWeight"
+                "view": "testExplorer",
+                "contents": "No test cases are listed because the Java Language Server is currently running in [LightWeight Mode](https://aka.ms/vscode-java-lightweight). To show test cases, click on the button to switch to Standard Mode.\n[Switch to Standard Mode](command:java.server.mode.switch?%5B%22Standard%22,true%5D)",
+                "when": "java:serverMode == LightWeight"
             }
         ],
         "menus": {
@@ -398,8 +398,9 @@
     "devDependencies": {
         "@types/fs-extra": "^5.1.0",
         "@types/lodash": "^4.14.150",
+        "@types/lru-cache": "^5.1.0",
         "@types/mocha": "^2.2.48",
-        "@types/node": "^6.14.10",
+        "@types/node": "^14.0.1",
         "@types/pug": "^2.0.4",
         "@types/sinon": "^9.0.3",
         "@types/vscode": "1.44.0",
@@ -414,7 +415,7 @@
         "sinon": "^9.0.2",
         "ts-loader": "^5.4.5",
         "tslint": "^5.20.1",
-        "typescript": "^2.8.3",
+        "typescript": "^4.0.2",
         "vscode-test": "^1.3.0",
         "webpack": "^4.43.0",
         "webpack-cli": "^3.3.11"
@@ -424,6 +425,7 @@
         "get-port": "^4.2.0",
         "iconv-lite": "^0.4.24",
         "lodash": "^4.17.19",
+        "lru-cache": "^6.0.0",
         "pug": "^2.0.4",
         "vscode-extension-telemetry-wrapper": "^0.8.0",
         "winston": "^3.2.1",

src/codelens/MovingAverage.ts

@@ -0,0 +1,18 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT license.
+
+export class MovingAverage {
+
+    private _n: number = 1;
+    private _val: number = 0;
+
+    public update(value: number): this {
+        this._val = this._val + (value - this._val) / this._n;
+        this._n += 1;
+        return this;
+    }
+
+    public get value(): number {
+        return this._val;
+    }
+}

src/codelens/TestCodeLensProvider.ts

@@ -1,16 +1,20 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 
-import { CancellationToken, CodeLens, CodeLensProvider, Disposable, Event, EventEmitter, TextDocument } from 'vscode';
+import * as LRUCache from 'lru-cache';
+import {performance} from 'perf_hooks';
+import { CancellationToken, CodeLens, CodeLensProvider, Disposable, Event, EventEmitter, TextDocument, Uri } from 'vscode';
 import { JavaTestRunnerCommands } from '../constants/commands';
 import { logger } from '../logger/logger';
 import { ITestItem, TestLevel } from '../protocols';
 import { ITestResult, TestStatus } from '../runners/models';
 import { testItemModel } from '../testItemModel';
 import { testResultManager } from '../testResultManager';
+import { MovingAverage } from './MovingAverage';
 
 export class TestCodeLensProvider implements CodeLensProvider, Disposable {
     private onDidChangeCodeLensesEmitter: EventEmitter<void> = new EventEmitter<void>();
+    private lruCache: LRUCache<Uri, MovingAverage> = new LRUCache<Uri, MovingAverage>(32);
     private isActivated: boolean = true;
 
     get onDidChangeCodeLenses(): Event<void> {
@@ -26,14 +30,24 @@ export class TestCodeLensProvider implements CodeLensProvider, Disposable {
         this.onDidChangeCodeLensesEmitter.fire();
     }
 
-    public async provideCodeLenses(document: TextDocument, _token: CancellationToken): Promise<CodeLens[]> {
+    public async provideCodeLenses(document: TextDocument, token: CancellationToken): Promise<CodeLens[]> {
         if (!this.isActivated) {
             return [];
         }
 
         try {
-            const items: ITestItem[] = await testItemModel.getItemsForCodeLens(document.uri);
-            return this.getCodeLenses(items);
+            const timeout: number = this.getRequestDelay(document.uri);
+            return new Promise<CodeLens[]>((resolve: (ids: CodeLens[]) => void): void => {
+                token.onCancellationRequested(() => {
+                    clearTimeout(timeoutHandle);
+                    resolve([]);
+                });
+
+                const timeoutHandle: NodeJS.Timeout = setTimeout(async () => {
+                   resolve(await this.resolveAllCodeLenses(document.uri, token));
+                }, timeout);
+
+            });
         } catch (error) {
             logger.error('Failed to provide Code Lens', error);
             return [];
@@ -44,6 +58,30 @@ export class TestCodeLensProvider implements CodeLensProvider, Disposable {
         this.onDidChangeCodeLensesEmitter.dispose();
     }
 
+    private getRequestDelay(uri: Uri): number {
+        const avg: MovingAverage | undefined = this.lruCache.get(uri);
+        if (!avg) {
+            return 350;
+        }
+        return Math.max(350, Math.floor(1.3 * avg.value));
+    }
+
+    private async resolveAllCodeLenses(uri: Uri, token: CancellationToken): Promise<CodeLens[]> {
+        if (token.isCancellationRequested) {
+            return [];
+        }
+
+        const startTime: number = performance.now();
+        const items: ITestItem[] = await testItemModel.getItemsForCodeLens(uri);
+        const result: CodeLens[] = this.getCodeLenses(items);
+        const executionTime: number = performance.now() - startTime;
+
+        const movingAverage: MovingAverage = this.lruCache.get(uri) || new MovingAverage();
+        movingAverage.update(executionTime);
+        this.lruCache.set(uri, movingAverage);
+        return result;
+    }
+
     private getCodeLenses(items: ITestItem[]): CodeLens[] {
         const codeLenses: CodeLens[] = [];
         for (const item of items) {

src/runners/baseRunner/BaseRunner.ts

@@ -4,7 +4,7 @@
 import * as fse from 'fs-extra';
 import { default as getPort } from 'get-port';
 import * as iconv from 'iconv-lite';
-import { createServer, Server, Socket } from 'net';
+import { AddressInfo, createServer, Server, Socket } from 'net';
 import * as os from 'os';
 import * as path from 'path';
 import { debug, DebugConfiguration, DebugSession, Disposable, Uri, workspace } from 'vscode';
@@ -141,7 +141,7 @@ export abstract class BaseRunner implements ITestRunner {
     }
 
     public get serverPort(): number {
-        const address: { port: number; family: string; address: string; } = this.server.address();
+        const address: AddressInfo = this.server.address() as AddressInfo;
         if (address) {
             return address.port;
         }
@@ -151,7 +151,7 @@ export abstract class BaseRunner implements ITestRunner {
 
     public getApplicationArgs(config?: IExecutionConfig): string[] {
         const applicationArgs: string[] = [];
-        applicationArgs.push(`${this.server.address().port}`);
+        applicationArgs.push(`${(this.server.address() as AddressInfo).port}`);
 
         applicationArgs.push(...this.getRunnerCommandParams(config));
 

src/runners/junitRunner/JunitRunner.ts

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 
+import { AddressInfo } from 'net';
 import { DebugConfiguration } from 'vscode';
 import { BaseRunner } from '../baseRunner/BaseRunner';
 import { BaseRunnerResultAnalyzer } from '../baseRunner/BaseRunnerResultAnalyzer';
@@ -15,9 +16,9 @@ export class JUnitRunner extends BaseRunner {
             const args: string[] = launchConfiguration.args as string[];
             const portIndex: number = args.lastIndexOf('-port');
             if (portIndex > -1 && portIndex + 1 < args.length) {
-                args[portIndex + 1] = `${this.server.address().port}`;
+                args[portIndex + 1] = `${(this.server.address() as AddressInfo).port}`;
             } else {
-                args.push('-port', `${this.server.address().port}`);
+                args.push('-port', `${(this.server.address() as AddressInfo).port}`);
             }
         }
         return super.run(launchConfiguration);