testingConsecutiveExecution.js

describe('executing handlers', () => {
    context('for synchronous handlers', () => {
        it('should happen in sequence', async () => {
            const hook1 = {
                event: 'preEventName',
                handler: sinon.spy()
            };
            const hook2 = {
                event: 'preEventName',
                handler: sinon.spy()
            };

            cacheInstance.addHooks([ hook1, hook2 ]);
            await getPreData('eventName', anyValidArgs);

            expect(hook1.handler).to.have.been.calledBefore(hook2.handler);
        });
    });

    context('for asynchronous handlers', () => {
        it('should happen in sequence', async () => {
            const stallFor = async (time) => await new Promise(resolve => setTimeout(resolve, time));
            const spyForSlowHandler = sinon.spy();
            const hook1 = {
                event: 'preEventName',
                handler: async () => {
                    await stallFor(50);
                    spyForSlowHandler();
                }
            };
            const hook2 = {
                event: 'preEventName',
                handler: sinon.spy()
            };

            cacheInstance.addHooks([ hook1, hook2 ]);
            await getPreData('eventName', anyValidArgs);

            expect(spyForSlowHandler).to.have.been.calledBefore(hook2.handler);
        });
    });
});