Run results for: stringify by concatenating or regex replacement or array joining

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:87.0) Gecko/20100101 Firefox/87.0

Browser: Firefox 87

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
concatenating with switch	969289.2 Ops/sec
regex replacement	2435141.0 Ops/sec
array joining	398633.0 Ops/sec
concatenating with object	267339.3 Ops/sec
concatenating with if	955004.9 Ops/sec

Script Preparation code:

window.input = 'This is an aexample of a templated literal supported in modern JavaScript: `test ${test}`.'

window.stringifyByConcatWithSwitch = str => {
  let res = '';
  for (let i = 0, l = str.length; i < l; ++i) {
    let chr = str.charAt(i);
    switch (chr) {
      case '\\': chr = '\\\\'; break
      case '`':  chr = '\\`';  break
      case '$':  chr = '\\$';  break
    }
    res += chr
  }
  return `\`${res}\``
}

window.stringifyByRegex = str => str.replace(/\\|`|\$(?={)/g, match => `\\${match}`)

window.stringifyByJoin = str => {
  let res = [];
  for (let i = 0, l = str.length; i < l; ++i) {
    let chr = str.charAt(i)
    switch (chr) {
      case '\\': chr = '\\\\'; break
      case '`':  chr = '\\`';  break
      case '$':  chr = '\\$';  break
    }
    res.push(chr)
  }
  return `\`${res.join()}\``
}

const escaped = {
  '\\': '\\\\',
  '`':  '\\`',
  '$':  '\\$'
}

window.stringifyByConcatWithObject = str => {
  let res = ''
  for (let i = 0, l = str.length; i < l; ++i) {
    let chr = str.charAt(i)
    res += escaped[chr] || chr
  }
  return `\`${res}\``
}

window.stringifyByConcatWithIf = str => {
  let res = '';
  for (let i = 0, l = str.length; i < l; ++i) {
    let chr = str.charAt(i)
    if (chr === '\\')     chr = '\\\\'
    else if (chr === '`') chr = '\\`'
    else if (chr === '$') chr = '\\$'
    res += chr
  }
  return `\`${res}\``
}

Tests:

concatenating with switch
stringifyByConcatWithSwitch(input)
regex replacement
stringifyByRegex(input)
array joining
stringifyByJoin(input)
concatenating with object
stringifyByConcatWithObject(input)
concatenating with if
stringifyByConcatWithIf(input)

Run results for: stringify by concatenating or regex replacement or array joining

concatenating with switch

regex replacement

array joining

concatenating with object

concatenating with if