gem-hunter

Drop-in replacement for the textarea component which automatically resizes textarea as content changes. A native React version of the popular jQuery Autosize! Weighs around 1.3KB (minified & gzipped).

This module supports IE9 and above.

import TextareaAutosize from 'react-textarea-autosize';

// If you use CommonJS syntax:
// var TextareaAutosize = require('react-textarea-autosize').default;

React.renderComponent(
  <div>
    <TextareaAutosize />
  </div>,
  document.getElementById('element'),
);

npm install react-textarea-autosize

https://andarist.github.io/react-textarea-autosize/

Apart from these, the component accepts all props that are accepted by <textarea/>, like style, onChange, value, etc.

Get a ref to inner textarea:

<TextareaAutosize ref={(tag) => (this.textarea = tag)} />

And then call a focus on that ref:

this.textarea.focus();

To autofocus:

<TextareaAutosize autoFocus />

(all HTML attributes are passed to inner textarea)

Because jest provides polyfills for DOM objects by requiring jsdom and react-test-renderer doesn't provide refs for rendered components out of the box (calling ref callbacks with null), you need to supply a mocked ref in your tests in you need it for your tests. You can do it like this (more can be read here):

const tree = renderer
  .create(<TextareaAutosize />, {
    createNodeMock: () => document.createElement('textarea'),
  })
  .toJSON();