메모리 누수를 방지하기 위해 모든 MutationObserver의 연결이 끊어졌는지 테스트하세요.

function setUpThemeClassObservers() { const observer = new MutationObserver(() => { const themeClass = this.getThemeClass(); this.fireStylesChangedEvent('themeChanged'); }); observer.observe(this.eGridDiv, { attributes: true, attributeFilter: ['class'], }); // we must disconnect otherwise "this" will not be GC'd // causing a memory leak return () => observer.disconnect(); }

describe('Mutation Observers Disconnected', () => { let originalMutationObserver: typeof MutationObserver; const allMockedObservers: any = []; const mutationObserverMock = jest.fn().mockImplementation(() => { const mock = { observe: jest.fn(), disconnect: jest.fn(), takeRecords: jest.fn(), }; allMockedObservers.push(mock); return mock; }); beforeEach(() => { // Ensure we can restore the real MutationObserver after the test originalMutationObserver = global.MutationObserver; global.MutationObserver = mutationObserverMock; }); afterEach(() => { global.MutationObserver = originalMutationObserver; }); test('observer always disconnected after destroy', async () => { const api = createGrid(); // Perform some actions if required to exercise the code paths api.destroy(); expect(allMockedObservers.length).toBeGreaterThan(0); for (const mock of allMockedObservers) { expect(mock.observe).toHaveBeenCalled(); expect(mock.disconnect).toHaveBeenCalled(); } }); });