kvendrik

<!--
  Prefetch HTML page the user might navigate to
  https://developer.mozilla.org/en-US/docs/Web/HTTP/Link_prefetching_FAQ
-->

<link rel="prefetch" href="/signup.html">

kvendrik

https://github.com/Shopify/polaris-react/blob/master/src/components/EventListener/EventListener.tsx but it saves events that are being set in context and merges the callback if appropriate. The goal is to improve performance and prevent cases where one page would have say 3 event listeners for the same event.

kvendrik

export default function showMessage(message: string) {
  console.log('message', message);

  return (...args: any[]) => {
    const [constructorOrComponent, propertyKey, descriptor] = args;

    if (typeof constructorOrComponent === 'function') {
      console.log('Class', constructorOrComponent);
      return constructorOrComponent;
    }

kvendrik

import * as React from 'react';
import {mount} from 'enzyme';
import {UnstyledLink, Button} from '../components';
import Link from '../Link';

describe('<Link />', () => {
  const mockProps = {
    children: 'Click me!',
  };

kvendrik

import * as React from 'react';
import {mount} from 'enzyme';
import {UnstyledLink, Button} from '../components';
import Link from '../Link';

describe('<Link />', () => {
  const mockProps = {
    children: 'Click me!',
  };

kvendrik

import * as React from 'react';
import {isExternal} from './utilities';
import {UnstyledLink, Button} from './components';

interface Props {
  children: React.ReactNode;
  href?: string;
  onClick?(): void;
}

kvendrik

import {trigger} from '@shopify/enzyme-utilities';

...

describe('onChange()', () => {
  it('triggers when the user types', () => {
    const onChangeSpy = jest.fn();
    const event = {};
    const textField = mount(
      <TextField {...mockProps} onChange={onChangeSpy} />,

kvendrik

describe('onChange()', () => {
  it('triggers when the user types', () => {
    const onChangeSpy = jest.fn();
    const event = {};
    const textField = mount(
      <TextField {...mockProps} onChange={onChangeSpy} />,
    );
    (textField.find('input').prop('onChange') as any)(event);
    expect(onChangeSpy).toHaveBeenCalledTimes(1);
  });

kvendrik

import * as React from 'react';
import {mount} from 'enzyme';
import {noop} from '@shopify/javascript-utilities/other';
import TextField from '../TextField';

describe('<TextField />', () => {
  const mockProps = {
    onChange: noop,
  };

kvendrik

import * as React from 'react';
import {mount} from 'enzyme';
import {noop} from '@shopify/javascript-utilities/other';
import TextField from '../TextField';

describe('<TextField />', () => {
  const mockProps = {
    onChange: noop,
  };