text: 
  import './setup'
  
  import tape from 'tape'
  
  import { initial } from '../src'
  
  tape('Initial state should contain stack and index', t => {
    t.plan(2)
  
    const navigation = initial.navigation
    const keys = Object.keys(navigation)
  
    t.ok(keys.includes('stack'), 'Navigation state key contains stack')
    t.ok(keys.includes('index'), 'Navigation state key contains index')
  })
  