Files
privacy.sexy/tests/unit/infrastructure/Threading/AsyncLazy.spec.ts
undergroundwires 36f0805590 unify usage of sleepAsync and add tests
The tests mock JS setTimeout API. However promise.resolve() is not working without flushing the promise queue (which could be done just by awaiting Promise.resolve()), similar issue has been discussed in facebook/jest#2157.
2021-05-04 19:10:23 +02:00

54 lines
1.8 KiB
TypeScript

import 'mocha';
import { expect } from 'chai';
import { AsyncLazy } from '@/infrastructure/Threading/AsyncLazy';
import { sleepAsync } from '@/infrastructure/Threading/AsyncSleep';
describe('AsyncLazy', () => {
it('returns value from lambda', async () => {
// arrange
const expected = 'test';
const lambda = () => Promise.resolve(expected);
const sut = new AsyncLazy(lambda);
// act
const actual = await sut.getValueAsync();
// assert
expect(actual).to.equal(expected);
});
describe('when running multiple times', () => {
// arrange
let totalExecuted: number = 0;
beforeEach(() => totalExecuted = 0);
it('when running sync', async () => {
// act
const sut = new AsyncLazy(() => {
totalExecuted++;
return Promise.resolve(totalExecuted);
});
const results = new Array<number>();
for (let i = 0; i < 5; i++) {
results.push(await sut.getValueAsync());
}
// assert
expect(totalExecuted).to.equal(1);
expect(results).to.deep.equal([1, 1, 1, 1, 1]);
});
it('when running long-running task in parallel', async () => {
// act
const sut = new AsyncLazy(async () => {
await sleepAsync(100);
totalExecuted++;
return Promise.resolve(totalExecuted);
});
const results = await Promise.all([
sut.getValueAsync(),
sut.getValueAsync(),
sut.getValueAsync(),
sut.getValueAsync(),
sut.getValueAsync()]);
// assert
expect(totalExecuted).to.equal(1);
expect(results).to.deep.equal([1, 1, 1, 1, 1]);
});
});
});