element-web/test/utils/promise-test.ts

58 lines
1.9 KiB
TypeScript

/*
* Copyright 2024 New Vector Ltd.
*
* SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only
* Please see LICENSE files in the repository root for full details.
*
*/
import { batch } from "../../src/utils/promise.ts";
describe("promise.ts", () => {
describe("batch", () => {
afterEach(() => jest.useRealTimers());
it("should batch promises into groups of a given size", async () => {
const promises = [() => Promise.resolve(1), () => Promise.resolve(2), () => Promise.resolve(3)];
const batchSize = 2;
const result = await batch(promises, batchSize);
expect(result).toEqual([1, 2, 3]);
});
it("should wait for the current batch to finish to request the next one", async () => {
jest.useFakeTimers();
let promise1Called = false;
const promise1 = () =>
new Promise<number>((resolve) => {
promise1Called = true;
resolve(1);
});
let promise2Called = false;
const promise2 = () =>
new Promise<number>((resolve) => {
promise2Called = true;
setTimeout(() => {
resolve(2);
}, 10);
});
let promise3Called = false;
const promise3 = () =>
new Promise<number>((resolve) => {
promise3Called = true;
resolve(3);
});
const batchSize = 2;
const batchPromise = batch([promise1, promise2, promise3], batchSize);
expect(promise1Called).toBe(true);
expect(promise2Called).toBe(true);
expect(promise3Called).toBe(false);
jest.advanceTimersByTime(11);
expect(await batchPromise).toEqual([1, 2, 3]);
});
});
});