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// Before
function getUserFriends(state): Friends[] {
  return state.me.friends;
}

// After
function getUserFriends(state): Friends[] {
  const friends = [];
  
  // Please never do this; it's only to illustrate the point

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{
  me: {
    id: 'bf6e74fe-9d41-4082-a48c-a2ce6d771da2',
    firstName: 'Sébastien',
    friendCount: 1,
    friend-1: {
      id: '7ccc3ebc-9310-426b-8e56-8d58f0a7ce2c',
      firstName: 'Peppa'
    }
  }

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{
  user: {
    id: 'bf6e74fe-9d41-4082-a48c-a2ce6d771da2',
    firstName: 'Sébastien',
    friends: [
      {
        id: '7ccc3ebc-9310-426b-8e56-8d58f0a7ce2c',
        firstName: 'Peppa'
      }
    ]

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cy.visit('http://www.google.com');
cy.title().should('eq', 'Google');
cy.get('input[type=text]').type('nightwatch');
cy.get('button[name=btnG]').click();
cy.contains('The Night Watch');

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client.
  url('http://www.google.com')
  .waitForElementVisible('body', 1000)
  .assert.title('Google')
  .assert.visible('input[type=text]')
  .setValue('input[type=text]', 'nightwatch')
  .waitForElementVisible('button[name=btnG]', 1000)
  .click('button[name=btnG]')
  .pause(1000)
  .assert.containsText('#main', 'The Night Watch')

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export function testId(id: string) {
  return `[data-testid="${id}"]`;
}

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{
  "env": {
    "production": {
      "plugins": [
        [
          "react-remove-properties",
          {
            "properties": [
              "data-testid"
            ]

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import { shallow } from 'enzyme';

describe('IncomingCalls component', () => {
  describe('given NO calls', () => {
    it('should render empty state', async () => {
      const component = createComponent({ calls: [] });

      expect(component.exists(testId('no-incoming-calls'))).toBeTruthy();
    });

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export function IncomingCalls({ calls }: Props) {
  return (
    <div>
      <p>
        Incoming Calls
      </p>

      {calls.length > 0 ?
        <div data-testid="incoming-call-list">
          {calls.map(call => <CallCard key={call.id} call={call} />)}