Enzyme: Method “text” is only meant to be run on a single node. 0 found instead

Use .first()

example const wrapper = shallow()

wrapper.find('h1 or p or .ClassName or #id').first();

import React from 'react'
import { shallow } from 'enzyme'
import renderer from 'react-test-renderer'
import About from '../pages/about.js'

describe('With Enzyme', () => {
  it('App shows "About"', () => {
    const about = shallow(
      <About />
   )
  expect(about.find('h1').first().text()).toEqual('About')
 })
})

Its caused by the fact that shallow does not render child componnets and your component been wrapped by a function. So shallow only returns a representation of the function not of the component. You can use dive() to reach the real component

/* global it, expect, describe */

import React from 'react'
import { shallow } from 'enzyme'
import renderer from 'react-test-renderer'
import About from '../pages/about.js'

describe('With Enzyme', () => {
  it('App shows "About"', () => {
    const about = shallow(
      <About />
    ).dive()
    expect(about.find('h1').text()).toEqual('About')
  })
})