PHP's print_r in JavaScript

module.exports = functionprint_r (array, returnVal) { // eslint-disable-line camelcase
//  discuss at: https://locutus.io/php/print_r/
// original by: Michael White (https://getsprink.com)
// improved by: Ben Bryan
// improved by: Brett Zamir (https://brett-zamir.me)
// improved by: Kevin van Zonneveld (https://kvz.io)
//    input by: Brett Zamir (https://brett-zamir.me)
//   example 1: print_r(1, true)
//   returns 1: '1'
const echo = require('../strings/echo')
let output = ''
const padChar = ' '
const padVal = 4
const _repeatChar = function (len, padChar) {
let str = ''
for (let i = 0; i < len; i++) {
      str += padChar
    }
return str
  }
var _formatArray = function (obj, curDepth, padVal, padChar) {
if (curDepth > 0) {
      curDepth++
    }
const basePad = _repeatChar(padVal * curDepth, padChar)
const thickPad = _repeatChar(padVal * (curDepth + 1), padChar)
let str = ''
if (typeof obj === 'object' &&
      obj !== null &&
      obj.constructor) {
      str += 'Array\n' + basePad + '(\n'
for (const key in obj) {
if (Object.prototype.toString.call(obj[key]) === '[object Array]') {
          str += thickPad
          str += '['
          str += key
          str += '] => '
          str += _formatArray(obj[key], curDepth + 1, padVal, padChar)
        } else {
          str += thickPad
          str += '['
          str += key
          str += '] => '
          str += obj[key]
          str += '\n'
        }
      }
      str += basePad + ')\n'
    } elseif (obj === null || obj === undefined) {
      str = ''
    } else {
// for our "resource" class
      str = obj.toString()
    }
return str
  }
  output = _formatArray(array, 0, padVal, padChar)
if (returnVal !== true) {
    echo(output)
returntrue
  }
return output
}