element-web/test/unit-tests/WorkerManager-test.ts

/*
Copyright 2024 New Vector Ltd.
Copyright 2023 The Matrix.org Foundation C.I.C.

SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
Please see LICENSE files in the repository root for full details.
*/

import { WorkerManager } from "../../src/WorkerManager";

describe("WorkerManager", () => {
    it("should generate consecutive sequence numbers for each call", () => {
        const postMessage = jest.fn();
        const manager = new WorkerManager({ postMessage } as unknown as Worker);

        manager.call({ data: "One" });
        manager.call({ data: "Two" });
        manager.call({ data: "Three" });

        const one = postMessage.mock.calls.find((c) => c[0].data === "One")!;
        const two = postMessage.mock.calls.find((c) => c[0].data === "Two")!;
        const three = postMessage.mock.calls.find((c) => c[0].data === "Three")!;

        expect(one[0].seq).toBe(0);
        expect(two[0].seq).toBe(1);
        expect(three[0].seq).toBe(2);
    });

    it("should support resolving out of order", async () => {
        const postMessage = jest.fn();
        const worker = { postMessage } as unknown as Worker;
        const manager = new WorkerManager(worker);

        const oneProm = manager.call({ data: "One" });
        const twoProm = manager.call({ data: "Two" });
        const threeProm = manager.call({ data: "Three" });

        const one = postMessage.mock.calls.find((c) => c[0].data === "One")![0].seq;
        const two = postMessage.mock.calls.find((c) => c[0].data === "Two")![0].seq;
        const three = postMessage.mock.calls.find((c) => c[0].data === "Three")![0].seq;

        worker.onmessage!({ data: { seq: one, data: 1 } } as MessageEvent);
        await expect(oneProm).resolves.toEqual(expect.objectContaining({ data: 1 }));

        worker.onmessage!({ data: { seq: three, data: 3 } } as MessageEvent);
        await expect(threeProm).resolves.toEqual(expect.objectContaining({ data: 3 }));

        worker.onmessage!({ data: { seq: two, data: 2 } } as MessageEvent);
        await expect(twoProm).resolves.toEqual(expect.objectContaining({ data: 2 }));
    });
});