css/docs/ClipboardCopy.js

import React from 'react'
import {findDOMNode} from 'react-dom'
import {Button} from '@primer/components'
import Octicon, {Clippy} from '@githubprimer/octicons-react'

export default class ClipboardCopy extends React.Component {
  copy() {
    const {value = ''} = this.props
    const {clipboard} = window.navigator
    const done = () => {
      // eslint-disable-next-line react/no-find-dom-node
      findDOMNode(this).dispatchEvent(new CustomEvent('copy', {bubbles: false}))
    }
    if (clipboard) {
      return clipboard.writeText(value).then(done)
    } else if (!document.body) {
      return
    } else {
      const node = document.createElement('pre')
      node.style.width = '1px'
      node.style.height = '1px'
      node.style.position = 'fixed'
      node.style.top = '5px'
      node.textContent = value

      const selection = window.getSelection()
      document.body.appendChild(node)
      selection.removeAllRanges()
      const range = document.createRange()
      range.selectNodeContents(node)
      selection.addRange(range)
      document.execCommand('copy')
      selection.removeAllRanges()
      document.body.removeChild(node)
    }
  }

  render() {
    // eslint-disable-next-line no-unused-vars
    const {value = '', ...rest} = this.props
    return (
      <Button onClick={() => this.copy()} type="button" {...rest}>
        <Octicon icon={Clippy} />
      </Button>
    )
  }
}