PHP's sprintf in JavaScript

module.exports = functionsprintf () {
//  discuss at: https://locutus.io/php/sprintf/
// original by: Ash Searle (https://hexmen.com/blog/)
// improved by: Michael White (https://getsprink.com)
// improved by: Jack
// improved by: Kevin van Zonneveld (https://kvz.io)
// improved by: Kevin van Zonneveld (https://kvz.io)
// improved by: Kevin van Zonneveld (https://kvz.io)
// improved by: Dj
// improved by: Allidylls
//    input by: Paulo Freitas
//    input by: Brett Zamir (https://brett-zamir.me)
// improved by: Rafał Kukawski (https://kukawski.pl)
//   example 1: sprintf("%01.2f", 123.1)
//   returns 1: '123.10'
//   example 2: sprintf("[%10s]", 'monkey')
//   returns 2: '[    monkey]'
//   example 3: sprintf("[%'#10s]", 'monkey')
//   returns 3: '[####monkey]'
//   example 4: sprintf("%d", 123456789012345)
//   returns 4: '123456789012345'
//   example 5: sprintf('%-03s', 'E')
//   returns 5: 'E00'
//   example 6: sprintf('%+010d', 9)
//   returns 6: '+000000009'
//   example 7: sprintf('%+0\'@10d', 9)
//   returns 7: '@@@@@@@@+9'
//   example 8: sprintf('%.f', 3.14)
//   returns 8: '3.140000'
//   example 9: sprintf('%% %2$d', 1, 2)
//   returns 9: '% 2'
const regex = /%%|%(?:(\d+)\$)?((?:[-+#0 ]|'[\s\S])*)(\d+)?(?:\.(\d*))?([\s\S])/g
const args = arguments
let i = 0
const format = args[i++]
const _pad = function (str, len, chr, leftJustify) {
if (!chr) {
      chr = ' '
    }
const padding = (str.length >= len) ? '' : newArray(1 + len - str.length >>> 0).join(chr)
return leftJustify ? str + padding : padding + str
  }
const justify = function (value, prefix, leftJustify, minWidth, padChar) {
const diff = minWidth - value.length
if (diff > 0) {
// when padding with zeros
// on the left side
// keep sign (+ or -) in front
if (!leftJustify && padChar === '0') {
        value = [
          value.slice(0, prefix.length),
          _pad('', diff, '0', true),
          value.slice(prefix.length)
        ].join('')
      } else {
        value = _pad(value, minWidth, padChar, leftJustify)
      }
    }
return value
  }
const _formatBaseX = function (value, base, leftJustify, minWidth, precision, padChar) {
// Note: casts negative numbers to positive ones
const number = value >>> 0
    value = _pad(number.toString(base), precision || 0, '0', false)
return justify(value, '', leftJustify, minWidth, padChar)
  }
// _formatString()
const _formatString = function (value, leftJustify, minWidth, precision, customPadChar) {
if (precision !== null && precision !== undefined) {
      value = value.slice(0, precision)
    }
return justify(value, '', leftJustify, minWidth, customPadChar)
  }
// doFormat()
const doFormat = function (substring, argIndex, modifiers, minWidth, precision, specifier) {
let number, prefix, method, textTransform, value
if (substring === '%%') {
return'%'
    }
// parse modifiers
let padChar = ' '// pad with spaces by default
let leftJustify = false
let positiveNumberPrefix = ''
let j, l
for (j = 0, l = modifiers.length; j < l; j++) {
switch (modifiers.charAt(j)) {
case' ':
case'0':
          padChar = modifiers.charAt(j)
break
case'+':
          positiveNumberPrefix = '+'
break
case'-':
          leftJustify = true
break
case"'":
if (j + 1 < l) {
            padChar = modifiers.charAt(j + 1)
            j++
          }
break
      }
    }
if (!minWidth) {
      minWidth = 0
    } else {
      minWidth = +minWidth
    }
if (!isFinite(minWidth)) {
thrownewError('Width must be finite')
    }
if (!precision) {
      precision = (specifier === 'd') ? 0 : 'fFeE'.indexOf(specifier) > -1 ? 6 : undefined
    } else {
      precision = +precision
    }
if (argIndex && +argIndex === 0) {
thrownewError('Argument number must be greater than zero')
    }
if (argIndex && +argIndex >= args.length) {
thrownewError('Too few arguments')
    }
    value = argIndex ? args[+argIndex] : args[i++]
switch (specifier) {
case'%':
return'%'
case's':
return _formatString(value + '', leftJustify, minWidth, precision, padChar)
case'c':
return _formatString(String.fromCharCode(+value), leftJustify, minWidth, precision, padChar)
case'b':
return _formatBaseX(value, 2, leftJustify, minWidth, precision, padChar)
case'o':
return _formatBaseX(value, 8, leftJustify, minWidth, precision, padChar)
case'x':
return _formatBaseX(value, 16, leftJustify, minWidth, precision, padChar)
case'X':
return _formatBaseX(value, 16, leftJustify, minWidth, precision, padChar)
          .toUpperCase()
case'u':
return _formatBaseX(value, 10, leftJustify, minWidth, precision, padChar)
case'i':
case'd':
        number = +value || 0
// Plain Math.round doesn't just truncate
        number = Math.round(number - number % 1)
        prefix = number < 0 ? '-' : positiveNumberPrefix
        value = prefix + _pad(String(Math.abs(number)), precision, '0', false)
if (leftJustify && padChar === '0') {
// can't right-pad 0s on integers
          padChar = ' '
        }
return justify(value, prefix, leftJustify, minWidth, padChar)
case'e':
case'E':
case'f': // @todo: Should handle locales (as per setlocale)
case'F':
case'g':
case'G':
        number = +value
        prefix = number < 0 ? '-' : positiveNumberPrefix
        method = ['toExponential', 'toFixed', 'toPrecision']['efg'.indexOf(specifier.toLowerCase())]
        textTransform = ['toString', 'toUpperCase']['eEfFgG'.indexOf(specifier) % 2]
        value = prefix + Math.abs(number)[method](precision)
return justify(value, prefix, leftJustify, minWidth, padChar)[textTransform]()
default:
// unknown specifier, consume that char and return empty
return''
    }
  }
try {
return format.replace(regex, doFormat)
  } catch (err) {
returnfalse
  }
}