"Pure emoji string" detection

emoji-utils.js

import emojiRegexCreator from 'emoji-regex';

const emojiRegex = emojiRegexCreator();

export default {

  isPureEmojiString(text) {
    if (!text || !text.trim()) return false;

    return text.replace(emojiRegex, '').trim() === '';
  },

};

emoji-utils.test.js

import { forOwn } from 'lodash';
import emoji from 'node-emoji';

import utils from '../utils';

const testStrings = {
  null: false,
  undefined: false,
  '': false,
  ' ': false,
  '\t': false,
  'hi': false,
  'Not emoji': false,
  'Not pure emoji :blush:': false,
  ':wink:': true,
  ':wink:!': false,
  ':notarealemoji:': false,
  ':sunglasses: :cactus:': true,
  ' \t :sunglasses: \t :cactus: \t ': true,
  '\u{1F609}': true, // :wink:
  '\u{1F60E} \u{1F335}': true, // :sunglasses: :cactus:
  '\u{0041}': false, // 'A'
};

describe('emoji utils', () => {
  forOwn(testStrings, (isPure, str) => {
    it(`recognizes '${str}' as ${isPure ? 'a' : 'NOT a'} pure emoji string`, () => {
      const emojiString = emoji.emojify(str);
      expect(utils.isPureEmojiString(emojiString)).toBe(isPure);
    });
  });
});

Benchmarked using http://jsben.ch/#/qpvoO to compare a few different regexes, this is about as fast as I could get it.