Updated useShadowRootElements to use the shadow root first child instead of flipping booleans to help with unneeded updates when the DOM doesn't change

Signed-off-by: Alex Lorenzi <alorenzi@spotify.com>
This commit is contained in:
Alex Lorenzi
2024-08-21 13:57:26 -04:00
parent f54d3a5385
commit e46dfec74d
4 changed files with 110 additions and 31 deletions
@@ -16,10 +16,22 @@
import { TechDocsAddonTester } from '@backstage/plugin-techdocs-addons-test-utils';
import React from 'react';
import { fireEvent, waitFor, act } from '@testing-library/react';
import { act, fireEvent, waitFor } from '@testing-library/react';
import { TextSize } from '../plugin';
import { useShadowRootElements } from '@backstage/plugin-techdocs-react';
jest.mock('@backstage/plugin-techdocs-react', () => ({
...jest.requireActual('@backstage/plugin-techdocs-react'),
useShadowRootElements: jest.fn(),
}));
describe('TextSize', () => {
const useShadowRootElementsMock = useShadowRootElements as jest.Mock;
beforeEach(() => {
useShadowRootElementsMock.mockReturnValue([]);
});
it('renders without exploding', async () => {
const { getByText } = await TechDocsAddonTester.buildAddonsInTechDocs([
<TextSize />,
@@ -36,6 +48,9 @@ describe('TextSize', () => {
.withDom(<body>TEST_CONTENT</body>)
.renderWithEffects();
const content = getByText('TEST_CONTENT');
useShadowRootElementsMock.mockReturnValue([content]);
fireEvent.click(getByTitle('Settings'));
await waitFor(() => {
@@ -60,7 +75,9 @@ describe('TextSize', () => {
let style = window.getComputedStyle(getByText('TEST_CONTENT'));
expect(style.getPropertyValue('--md-typeset-font-size')).toBe('18.4px');
await waitFor(() => {
expect(style.getPropertyValue('--md-typeset-font-size')).toBe('18.4px');
});
fireEvent.keyDown(slider, {
key: 'ArrowLeft',
@@ -88,6 +105,9 @@ describe('TextSize', () => {
.withDom(<body>TEST_CONTENT</body>)
.renderWithEffects();
const content = getByText('TEST_CONTENT');
useShadowRootElementsMock.mockReturnValue([content]);
fireEvent.click(getByTitle('Settings'));
await waitFor(() => {
+51 -2
View File
@@ -19,7 +19,7 @@ import {
useShadowRootElements,
useShadowRootSelection,
} from './hooks';
import { renderHook } from '@testing-library/react';
import { act, renderHook } from '@testing-library/react';
import { fireEvent, waitFor } from '@testing-library/react';
const fireSelectionChangeEvent = (window: Window) => {
@@ -34,7 +34,7 @@ const getSelection = jest.fn();
const mockShadowRoot = () => {
const div = document.createElement('div');
const shadowRoot = div.attachShadow({ mode: 'open' });
shadowRoot.innerHTML = '<h1>Shadow DOM Mock</h1>';
shadowRoot.innerHTML = '<div><h1>Shadow DOM Mock</h1></div>';
(shadowRoot as ShadowRoot & Pick<Document, 'getSelection'>).getSelection =
getSelection;
return shadowRoot;
@@ -85,6 +85,55 @@ describe('hooks', () => {
expect(result.current).toHaveLength(1);
});
it('should update elements if shadow root changes', async () => {
const { result, rerender } = renderHook(() =>
useShadowRootElements(['h1']),
);
act(() => {
shadowRoot.innerHTML = '<div><h1>Updated Shadow DOM Mock</h1></div>';
rerender();
});
await waitFor(() => {
expect(result.current[0].textContent).toBe('Updated Shadow DOM Mock');
});
});
describe('mutation observer', () => {
const observer: jest.Mocked<MutationObserver> = {
observe: jest.fn(),
disconnect: jest.fn(),
takeRecords: jest.fn(),
};
beforeEach(() => {
jest
.spyOn(window, 'MutationObserver')
.mockImplementation(() => observer);
});
afterEach(() => {
jest.clearAllMocks();
});
it('should observe shadow root changes', async () => {
renderHook(() => useShadowRootElements(['h1']));
expect(observer.observe).toHaveBeenCalledWith(shadowRoot, {
childList: true,
attributes: true,
characterData: true,
subtree: true,
});
});
it('should disconnect observer on unmount', async () => {
const { unmount } = renderHook(() => useShadowRootElements(['h1']));
unmount();
expect(observer.disconnect).toHaveBeenCalled();
});
});
});
describe('useShadowRootSelection', () => {
+5 -5
View File
@@ -39,13 +39,13 @@ export const useShadowRootElements = <
selectors: string[],
): TReturnedElement[] => {
const shadowRoot = useShadowRoot();
const [render, rerender] = useState(false);
const [root, setRootNode] = useState(shadowRoot?.firstChild);
useEffect(() => {
let observer: MutationObserver;
if (shadowRoot) {
observer = new MutationObserver(() => {
rerender(!render);
setRootNode(shadowRoot?.firstChild);
});
observer.observe(shadowRoot, {
attributes: true,
@@ -55,12 +55,12 @@ export const useShadowRootElements = <
});
}
return () => observer?.disconnect();
}, [shadowRoot, render, rerender]);
}, [shadowRoot]);
if (!shadowRoot) return [];
if (!root || !(root instanceof HTMLElement)) return [];
return selectors
.map(selector => shadowRoot.querySelectorAll<TReturnedElement>(selector))
.map(selector => root.querySelectorAll<TReturnedElement>(selector))
.filter(nodeList => nodeList.length)
.map(nodeList => Array.from(nodeList))
.flat();
@@ -20,6 +20,7 @@ import { CompoundEntityRef } from '@backstage/catalog-model';
import {
techdocsApiRef,
TechDocsReaderPageProvider,
useShadowRootElements,
} from '@backstage/plugin-techdocs-react';
import { renderInTestApp, TestApiProvider } from '@backstage/test-utils';
@@ -36,6 +37,7 @@ jest.mock('../useReaderState', () => ({
jest.mock('@backstage/plugin-techdocs-react', () => ({
...jest.requireActual('@backstage/plugin-techdocs-react'),
useShadowDomStylesLoading: jest.fn().mockReturnValue(false),
useShadowRootElements: jest.fn(),
}));
import { TechDocsReaderPageContent } from './TechDocsReaderPageContent';
@@ -88,6 +90,12 @@ const Wrapper = ({
);
describe('<TechDocsReaderPageContent />', () => {
const useShadowRootElementsMock = useShadowRootElements as jest.Mock;
beforeEach(() => {
useShadowRootElementsMock.mockReturnValue([]);
});
afterEach(() => {
jest.clearAllMocks();
});
@@ -154,6 +162,29 @@ describe('<TechDocsReaderPageContent />', () => {
});
});
it('should scroll to header if hash is not present in url', async () => {
jest.spyOn(document, 'querySelector');
getEntityMetadata.mockResolvedValue(mockEntityMetadata);
getTechDocsMetadata.mockResolvedValue(mockTechDocsMetadata);
useTechDocsReaderDom.mockReturnValue(document.createElement('html'));
useReaderState.mockReturnValue({ state: 'cached' });
const rendered = await renderInTestApp(
<Wrapper>
<TechDocsReaderPageContent withSearch={false} />
</Wrapper>,
);
await waitFor(() => {
expect(
rendered.getByTestId('techdocs-native-shadowroot'),
).toBeInTheDocument();
expect(document.querySelector).toHaveBeenCalledWith('header');
});
});
it('should scroll to hash if hash is present in url', async () => {
jest.spyOn(document, 'querySelector');
@@ -165,6 +196,7 @@ describe('<TechDocsReaderPageContent />', () => {
const mockTechDocsPage = document.createElement('html');
mockTechDocsPage.appendChild(h2);
useShadowRootElementsMock.mockReturnValue([h2]);
getEntityMetadata.mockResolvedValue(mockEntityMetadata);
getTechDocsMetadata.mockResolvedValue(mockTechDocsMetadata);
useTechDocsReaderDom.mockReturnValue(mockTechDocsPage);
@@ -188,26 +220,4 @@ describe('<TechDocsReaderPageContent />', () => {
window.location.hash = '';
});
it('should scroll to header if hash is not present in url', async () => {
jest.spyOn(document, 'querySelector');
getEntityMetadata.mockResolvedValue(mockEntityMetadata);
getTechDocsMetadata.mockResolvedValue(mockTechDocsMetadata);
useTechDocsReaderDom.mockReturnValue(document.createElement('html'));
useReaderState.mockReturnValue({ state: 'cached' });
const rendered = await renderInTestApp(
<Wrapper>
<TechDocsReaderPageContent withSearch={false} />
</Wrapper>,
);
await waitFor(() => {
expect(
rendered.getByTestId('techdocs-native-shadowroot'),
).toBeInTheDocument();
expect(document.querySelector).toHaveBeenCalledWith('header');
});
});
});