element-web/test/unit-tests/utils/Singleflight-test.ts

101 lines
3.4 KiB
TypeScript

/*
Copyright 2024 New Vector Ltd.
Copyright 2021 The Matrix.org Foundation C.I.C.
SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only
Please see LICENSE files in the repository root for full details.
*/
import { Singleflight } from "../../../src/utils/Singleflight";
describe("Singleflight", () => {
afterEach(() => {
Singleflight.forgetAll();
});
it("should throw for bad context variables", () => {
const permutations: [object | null, string | null][] = [
[null, null],
[{}, null],
[null, "test"],
];
for (const p of permutations) {
expect(() => Singleflight.for(p[0], p[1])).toThrow("An instance and key must be supplied");
}
});
it("should execute the function once", () => {
const instance = {};
const key = "test";
const val = {}; // unique object for reference check
const fn = jest.fn().mockReturnValue(val);
const sf = Singleflight.for(instance, key);
const r1 = sf.do(fn);
expect(r1).toBe(val);
expect(fn.mock.calls.length).toBe(1);
const r2 = sf.do(fn);
expect(r2).toBe(val);
expect(fn.mock.calls.length).toBe(1);
});
it("should execute the function once, even with new contexts", () => {
const instance = {};
const key = "test";
const val = {}; // unique object for reference check
const fn = jest.fn().mockReturnValue(val);
let sf = Singleflight.for(instance, key);
const r1 = sf.do(fn);
expect(r1).toBe(val);
expect(fn.mock.calls.length).toBe(1);
sf = Singleflight.for(instance, key); // RESET FOR TEST
const r2 = sf.do(fn);
expect(r2).toBe(val);
expect(fn.mock.calls.length).toBe(1);
});
it("should execute the function twice if the result was forgotten", () => {
const instance = {};
const key = "test";
const val = {}; // unique object for reference check
const fn = jest.fn().mockReturnValue(val);
const sf = Singleflight.for(instance, key);
const r1 = sf.do(fn);
expect(r1).toBe(val);
expect(fn.mock.calls.length).toBe(1);
sf.forget();
const r2 = sf.do(fn);
expect(r2).toBe(val);
expect(fn.mock.calls.length).toBe(2);
});
it("should execute the function twice if the instance was forgotten", () => {
const instance = {};
const key = "test";
const val = {}; // unique object for reference check
const fn = jest.fn().mockReturnValue(val);
const sf = Singleflight.for(instance, key);
const r1 = sf.do(fn);
expect(r1).toBe(val);
expect(fn.mock.calls.length).toBe(1);
Singleflight.forgetAllFor(instance);
const r2 = sf.do(fn);
expect(r2).toBe(val);
expect(fn.mock.calls.length).toBe(2);
});
it("should execute the function twice if everything was forgotten", () => {
const instance = {};
const key = "test";
const val = {}; // unique object for reference check
const fn = jest.fn().mockReturnValue(val);
const sf = Singleflight.for(instance, key);
const r1 = sf.do(fn);
expect(r1).toBe(val);
expect(fn.mock.calls.length).toBe(1);
Singleflight.forgetAll();
const r2 = sf.do(fn);
expect(r2).toBe(val);
expect(fn.mock.calls.length).toBe(2);
});
});