1// Copyright (C) 2024 The Android Open Source Project 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// http://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14 15import {AsyncGuard} from './async_guard'; 16import {defer} from './deferred'; 17 18test('AsyncGuard', async () => { 19 const guard = new AsyncGuard<number>(); 20 let counter = 0; 21 22 for (let i = 1; i <= 3; i++) { 23 const barrier = defer<void>(); 24 const asyncTask = async () => { 25 await barrier; 26 return ++counter; 27 }; 28 const promises = [ 29 guard.run(asyncTask), 30 guard.run(asyncTask), 31 guard.run(asyncTask), 32 ]; 33 setTimeout(() => barrier.resolve(), 0); 34 await barrier; 35 expect(await Promise.all(promises)).toEqual([i, i, i]); 36 } 37}); 38