nonsense.js

module.exports = {
  characters: ['᠎', '​'],
  encode: function (input) {
    var output = ''
    var binary = ''
    for (var char = 0; char < input.length; char++) {
      var dec = input.charCodeAt(char).toString(2)
      binary += Array(9 - dec.length).join('0') + dec
    }
    for (var bit = 0; bit < binary.length; bit++) {
      output += this.characters[binary.charAt(bit)]
    }
    return output
  },
  decode: function (input) {
    var output = ''
    var binary = ''
    for (var char = 0; char < input.length; char++) {
      binary += this.characters.indexOf(input[char])
    }
    for (var byte = 0; byte < binary.length / 8; byte++) {
      output += String.fromCharCode(parseInt(binary.substr(byte * 8, 8), 2))
    }
    return output
  }
}

// Only works with Unicode characters up to 255
// $ node
// > var nonsense = require('./nonsense.js')
// undefined
// > nonsense.encode('Hello')
// '᠎​᠎᠎​᠎᠎᠎᠎​​᠎᠎​᠎​᠎​​᠎​​᠎᠎᠎​​᠎​​᠎᠎᠎​​᠎​​​​'
// > nonsense.decode('᠎​᠎᠎​᠎᠎᠎᠎​​᠎᠎​᠎​᠎​​᠎​​᠎᠎᠎​​᠎​​᠎᠎᠎​​᠎​​​​')
// 'Hello'
// > nonsense.characters = ['A', 'B']
// [ 'A', 'B' ]
// > nonsense.encode('Hello')
// 'ABAABAAAABBAABABABBABBAAABBABBAAABBABBBB'
// > nonsense.decode('ABAABAAAABBAABABABBABBAAABBABBAAABBABBBB')
// 'Hello'