regex.js

/**
 * Created by chenzhuokai on 16/6/3.
 */
const fs = require('fs-extra')
const _ = require('lodash')

let emojiList = fs.readJsonSync(__dirname + '/emoji.json')
const fromCharCode = String.fromCharCode
const unicodeToJsEscape = require('unicode-escape')

let unicodeList = emojiList.map(function (emoji) {
  emoji.converted = emoji.unicode.replace(/U\+/g, '').replace(/\s/g, '-')
  return emoji
}).filter(emoji => /U\+/.test(emoji.unicode))

unicodeList = _.sortBy(unicodeList, function (unicode) {
  return -(unicodeToJsEscape(unicode.converted).length)
})

unicodeList = unicodeList.map(function (unicode) {
  unicode.converted = unicodeToJsEscape(unicode.converted.split('-').map(fromCodePoint).join(''))
  return unicode
})

console.log('Exporting json')
fs.outputJsonSync(__dirname + '/unicode.json', unicodeList)

console.log('Exporting regex-es5.txt')
let regexEs5Txt = unicodeList.map((u) => {
  return u.converted.replace('\\ufe0f\\u20e3', '\\ufe0f?\\u20e3')
}).join('|')
fs.outputFileSync(__dirname + '/regex-es5.txt', regexEs5Txt)

console.log('Exporting regex-es6.txt')
fs.outputFileSync(__dirname + '/regex-es6.txt', unicodeList.map((u) => {
  return u.unicode.replace(/\s/g, '').replace(/U\+([0-9A-F]+)/ig, '\\u{$1}').toLocaleLowerCase()
}).join('|'))

console.log('Exporting regex-python.txt')
fs.outputFileSync(__dirname + '/regex-python.txt', unicodeList.map((u) => {
  let unicode = u.unicode.replace(/\s/g, '')
  return unicode.split('U+').map(char => {
    if (!char) {
      return ''
    }
    return '\\U' + _.padStart(char, 8, '0')
  }).join('')
}).join('|'))

console.log('Exporting emoji-parser.js')
let jsFile = fs.readFileSync('./emoji-parser.js.template').toString()
jsFile = jsFile.replace('<% regex-es5 %>', regexEs5Txt)
jsFile = `/* Generated at ${new Date()} */\n` + jsFile
fs.outputFileSync('emoji-parser.js', jsFile)

function fromCodePoint(codepoint) {
  let code = typeof codepoint === 'string' ?
    parseInt(codepoint, 16) : codepoint
  if (code < 0x10000) {
    return fromCharCode(code)
  }
  code -= 0x10000
  return fromCharCode(
    0xD800 + (code >> 10),
    0xDC00 + (code & 0x3FF)
  )
}