<CommentList />

CommentList.js

import React, { Component } from 'react'
import Loading from './Loading'

class CommentList extends Component {
  render() {
    const { isLoading, comments } = this.props

    if (isLoading) return <Loading />
    return (
      <ul>
        {
          comments.map(({ id, body }) => <li key={id}>{body}</li>)
        }
      </ul>
    )
  }
}

export default CommentList