ErrorPro

function sum(a, b) {
  return a + b;
}

ErrorPro

import React, { Component } from 'react';
import PropTypes from 'prop-types';

class Button extends Component {
  state = {
    counter: 0,
  }

  render() {
    const { label, onClick } = this.props;

ErrorPro

import React from 'react';
import Button from './Button';
import renderer from 'react-test-renderer';
import Enzyme, { mount } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';

Enzyme.configure({ adapter: new Adapter() });

/* other tests */

ErrorPro

import React, { Component } from 'react';

const DumpComponent = props => (
  <button onClick={props.onClick}>{props.label}</button>
);

// or

class DumpComponent extends Component {
  render() {

ErrorPro

import sum from './sum';

test('pure function returns the same output for the same input', () => {
  expect(sum(2, 2)).toBe(4);
});

ErrorPro

import React from 'react';
import Dump from './Dump';
import renderer from 'react-test-renderer';

test('dump components renders initially', () => {
  const component = renderer.create(
    <Dump onChange={() => {}} label="Hi i am a dump component" />
  );

  expect(component.toJSON()).toMatchSnapshot();

ErrorPro

import React from 'react';
import Button from './Button';
import renderer from 'react-test-renderer';
import Enzyme, { mount } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';

Enzyme.configure({ adapter: new Adapter() });

/* other tests */

ErrorPro

import React from 'react';
import Button from './Button';
import renderer from 'react-test-renderer';

test('renders button with passed props', () => {
  const component = renderer.create(
    <Button onClick={() => {}} label="test label" />
  );

  expect(component.toJSON()).toMatchSnapshot();

ErrorPro

import React from 'react';
import Button from './Button';
import renderer from 'react-test-renderer';

/* other tests */

test('renders with 0 as an initial state of counter', () => {
  const component = renderer.create(
    <Button onClick={() => {}} label="this is test label" />
  );

ErrorPro

`
  query UserQuery {
    user {
      firstName
      lastName
    }
  }
`