clients/spec/common/misc/sequentialize.spec.ts

import { sequentialize } from '../../../src/misc/sequentialize';

describe('sequentialize decorator', () => {
    it('should call the function once', async () => {
        const foo = new Foo();
        const promises = [];
        for (let i = 0; i < 10; i++) {
            promises.push(foo.bar(1));
        }
        await Promise.all(promises);

        expect(foo.calls).toBe(1);
    });

    it('should call the function once for each instance of the object', async () => {
        const foo = new Foo();
        const foo2 = new Foo();
        const promises = [];
        for (let i = 0; i < 10; i++) {
            promises.push(foo.bar(1));
            promises.push(foo2.bar(1));
        }
        await Promise.all(promises);

        expect(foo.calls).toBe(1);
        expect(foo2.calls).toBe(1);
    });

    it('should call the function once with key function', async () => {
        const foo = new Foo();
        const promises = [];
        for (let i = 0; i < 10; i++) {
            promises.push(foo.baz(1));
        }
        await Promise.all(promises);

        expect(foo.calls).toBe(1);
    });

    it('should call the function again when already resolved', async () => {
        const foo = new Foo();
        await foo.bar(1);
        expect(foo.calls).toBe(1);
        await foo.bar(1);
        expect(foo.calls).toBe(2);
    });

    it('should call the function again when already resolved with a key function', async () => {
        const foo = new Foo();
        await foo.baz(1);
        expect(foo.calls).toBe(1);
        await foo.baz(1);
        expect(foo.calls).toBe(2);
    });

    it('should call the function for each argument', async () => {
        const foo = new Foo();
        await Promise.all([
            foo.bar(1),
            foo.bar(1),
            foo.bar(2),
            foo.bar(2),
            foo.bar(3),
            foo.bar(3),
        ]);
        expect(foo.calls).toBe(3);
    });

    it('should call the function for each argument with key function', async () => {
        const foo = new Foo();
        await Promise.all([
            foo.baz(1),
            foo.baz(1),
            foo.baz(2),
            foo.baz(2),
            foo.baz(3),
            foo.baz(3),
        ]);
        expect(foo.calls).toBe(3);
    });

    it('should return correct result for each call', async () => {
        const foo = new Foo();
        const allRes: number[] = [];

        await Promise.all([
            foo.bar(1).then((res) => allRes.push(res)),
            foo.bar(1).then((res) => allRes.push(res)),
            foo.bar(2).then((res) => allRes.push(res)),
            foo.bar(2).then((res) => allRes.push(res)),
            foo.bar(3).then((res) => allRes.push(res)),
            foo.bar(3).then((res) => allRes.push(res)),
        ]);
        expect(foo.calls).toBe(3);
        expect(allRes.length).toBe(6);
        allRes.sort();
        expect(allRes).toEqual([2, 2, 4, 4, 6, 6]);
    });

    it('should return correct result for each call with key function', async () => {
        const foo = new Foo();
        const allRes: number[] = [];

        await Promise.all([
            foo.baz(1).then((res) => allRes.push(res)),
            foo.baz(1).then((res) => allRes.push(res)),
            foo.baz(2).then((res) => allRes.push(res)),
            foo.baz(2).then((res) => allRes.push(res)),
            foo.baz(3).then((res) => allRes.push(res)),
            foo.baz(3).then((res) => allRes.push(res)),
        ]);
        expect(foo.calls).toBe(3);
        expect(allRes.length).toBe(6);
        allRes.sort();
        expect(allRes).toEqual([3, 3, 6, 6, 9, 9]);
    });
});

class Foo {
    calls = 0;

    @sequentialize((args) => 'bar' + args[0])
    bar(a: number): Promise<number> {
        this.calls++;
        return new Promise((res) => {
            setTimeout(() => {
                res(a * 2);
            }, Math.random() * 100);
        });
    }

    @sequentialize((args) => 'baz' + args[0])
    baz(a: number): Promise<number> {
        this.calls++;
        return new Promise((res) => {
            setTimeout(() => {
                res(a * 3);
            }, Math.random() * 100);
        });
    }
}