refactor(Task): Refactor task to use Promise.race

Don't reinvent the wheel
stryker-mutator · Jul 24, 2018 · cb63eab · cb63eab
1 parent dd2ee86
commit cb63eab
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Showing 7 changed files with 28 additions and 42 deletions.
diff --git a/packages/stryker/src/child-proxy/ChildProcessProxy.ts b/packages/stryker/src/child-proxy/ChildProcessProxy.ts
@@ -4,7 +4,7 @@ import { File } from 'stryker-api/core';
 import { getLogger } from 'stryker-api/logging';
 import { WorkerMessage, WorkerMessageKind, ParentMessage, autoStart, ParentMessageKind } from './messageProtocol';
 import { serialize, deserialize, kill, isErrnoException } from '../utils/objectUtils';
-import Task from '../utils/Task';
+import { Task, ExpirableTask } from '../utils/Task';
 import LoggingClientContext from '../logging/LoggingClientContext';
 import StrykerError from '../utils/StrykerError';
 import ChildProcessCrashedError from './ChildProcessCrashedError';
@@ -24,7 +24,7 @@ export default class ChildProcessProxy<T> {
 
   private worker: ChildProcess;
   private initTask: Task;
-  private disposeTask: Task<void> | undefined;
+  private disposeTask: ExpirableTask<void> | undefined;
   private currentError: StrykerError | undefined;
   private workerTasks: Task<any>[] = [];
   private log = getLogger(ChildProcessProxy.name);
@@ -203,7 +203,7 @@ export default class ChildProcessProxy<T> {
         kill(this.worker.pid);
         this.isDisposed = true;
       };
-      this.disposeTask = new Task(TIMEOUT_FOR_DISPOSE);
+      this.disposeTask = new ExpirableTask(TIMEOUT_FOR_DISPOSE);
       this.send({ kind: WorkerMessageKind.Dispose });
       return this.disposeTask.promise
         .then(killWorker)

diff --git a/packages/stryker/src/utils/Task.ts b/packages/stryker/src/utils/Task.ts
@@ -1,59 +1,48 @@
+import { sleep } from './objectUtils';
 
 /**
  * Wraps a promise in a Task api for convenience.
  */
-export default class Task<T = void> {
+export class Task<T = void> {
 
-  private _promise: Promise<T>;
+  protected _promise: Promise<T>;
   private resolveFn: (value?: T | PromiseLike<T>) => void;
   private rejectFn: (reason: any) => void;
   private _isResolved = false;
-  private timeout: NodeJS.Timer;
 
-  constructor(timeoutMs?: number, private timeoutHandler?: () => PromiseLike<T>) {
+  constructor() {
     this._promise = new Promise<T>((resolve, reject) => {
       this.resolveFn = resolve;
       this.rejectFn = reject;
     });
-    if (timeoutMs) {
-      this.timeout = setTimeout(() => this.handleTimeout(), timeoutMs);
-    }
-  }
-
-  get isResolved() {
-    return this._isResolved;
   }
 
   get promise() {
     return this._promise;
   }
 
-  handleTimeout() {
-    if (this.timeoutHandler) {
-      this.timeoutHandler().then(val => this.resolve(val));
-    } else {
-      this.resolve(undefined);
-    }
-  }
-
-  chainTo(promise: Promise<T>) {
-    promise.then(value => this.resolve(value), reason => this.reject(reason));
+  get isResolved() {
+    return this._isResolved;
   }
 
   resolve(result: undefined | T | PromiseLike<T>) {
-    this.resolveTimeout();
+    this._isResolved = true;
     this.resolveFn(result);
   }
 
   reject(reason: any) {
-    this.resolveTimeout();
+    this._isResolved = true;
     this.rejectFn(reason);
   }
+}
 
-  private resolveTimeout() {
-    if (this.timeout) {
-      clearTimeout(this.timeout);
-    }
-    this._isResolved = true;
+/**
+ * A task that can expire after the given time.
+ * If that happens, the inner promise is resolved
+ */
+export class ExpirableTask<T = void> extends Task<T | void> {
+  constructor(timeoutMS: number) {
+    super();
+    this._promise = Promise.race([this._promise, sleep(timeoutMS)]);
   }
 }
diff --git a/packages/stryker/src/utils/objectUtils.ts b/packages/stryker/src/utils/objectUtils.ts
@@ -102,7 +102,7 @@ export function kill(pid: number): Promise<void> {
   });
 }
 
-export function sleep(ms: number) {
+export function sleep(ms: number): Promise<void> {
   return new Promise(res => {
     setTimeout(res, ms);
   });

diff --git a/packages/stryker/test/integration/child-proxy/ChildProcessProxy.it.ts b/packages/stryker/test/integration/child-proxy/ChildProcessProxy.it.ts
@@ -6,7 +6,7 @@ import { File, LogLevel } from 'stryker-api/core';
 import { Logger } from 'stryker-api/logging';
 import Echo from './Echo';
 import ChildProcessProxy from '../../../src/child-proxy/ChildProcessProxy';
-import Task from '../../../src/utils/Task';
+import { Task } from '../../../src/utils/Task';
 import LoggingServer from '../../helpers/LoggingServer';
 import { filter } from 'rxjs/operators';
 import { Mock } from '../../helpers/producers';

diff --git a/packages/stryker/test/unit/SandboxPoolSpec.ts b/packages/stryker/test/unit/SandboxPoolSpec.ts
@@ -6,10 +6,11 @@ import { File, LogLevel } from 'stryker-api/core';
 import { TestFramework } from 'stryker-api/test_framework';
 import Sandbox from '../../src/Sandbox';
 import SandboxPool from '../../src/SandboxPool';
-import Task from '../../src/utils/Task';
+import { Task } from '../../src/utils/Task';
 import '../helpers/globals';
 import { Mock, config, file, mock, testFramework } from '../helpers/producers';
 import LoggingClientContext from '../../src/logging/LoggingClientContext';
+import { sleep } from '../../src/utils/objectUtils';
 
 const OVERHEAD_TIME_MS = 42;
 const LOGGING_CONTEXT: LoggingClientContext = Object.freeze({
@@ -117,8 +118,6 @@ describe('SandboxPool', () => {
 });
 
 function tick() {
-  return new Promise(res => {
-    setTimeout(res, 0);
-  });
+  return sleep(0);
 }
 
diff --git a/packages/stryker/test/unit/test-runner/ChildProcessTestRunnerDecoratorSpec.ts b/packages/stryker/test/unit/test-runner/ChildProcessTestRunnerDecoratorSpec.ts
@@ -8,7 +8,7 @@ import ChildProcessProxy from '../../../src/child-proxy/ChildProcessProxy';
 import LoggingClientContext from '../../../src/logging/LoggingClientContext';
 import ChildProcessTestRunnerWorker from '../../../src/test-runner/ChildProcessTestRunnerWorker';
 import TestRunnerDecorator from '../../../src/test-runner/TestRunnerDecorator';
-import Task from '../../../src/utils/Task';
+import { Task } from '../../../src/utils/Task';
 import ChildProcessCrashedError from '../../../src/child-proxy/ChildProcessCrashedError';
 
 describe(ChildProcessTestRunnerDecorator.name, () => {

diff --git a/packages/stryker/test/unit/transpiler/MutantTranspilerSpec.ts b/packages/stryker/test/unit/transpiler/MutantTranspilerSpec.ts
@@ -6,7 +6,7 @@ import ChildProcessProxy from '../../../src/child-proxy/ChildProcessProxy';
 import MutantTranspiler from '../../../src/transpiler/MutantTranspiler';
 import TranspileResult from '../../../src/transpiler/TranspileResult';
 import TranspilerFacade, * as transpilerFacade from '../../../src/transpiler/TranspilerFacade';
-import { errorToString } from '../../../src/utils/objectUtils';
+import { errorToString, sleep } from '../../../src/utils/objectUtils';
 import '../../helpers/globals';
 import { Mock, config, file, mock, testableMutant } from '../../helpers/producers';
 import LoggingClientContext from '../../../src/logging/LoggingClientContext';
@@ -157,9 +157,7 @@ describe('MutantTranspiler', () => {
         ];
         expect(actualResults).deep.eq(expectedResults);
       });
-      const nextTick = () => new Promise(res => {
-        setTimeout(res, 0);
-      });
+      const nextTick = () => sleep(0);
     });
   });