old_contents: 'use strict';
  
  var zero = function (n, max) {
    n = n.toString(16).toUpperCase();
    while (n.length < max) {
      n = '0' + n;
    }
    return n;
  };
  
  module.exports = function (buffer) {
    var rows = Math.ceil(buffer.length / 16);
    var last = buffer.length % 16 || 16;
    var offsetLength = buffer.length.toString(16).length;
    if (offsetLength < 6) offsetLength = 6;
  
    var str = 'Offset';
    while (str.length < offsetLength) {
      str += ' ';
    }
  
    str = /*'\u001b[36m' +*/ str + '  ';
  
    var i;
    for (i = 0; i < 16; i++) {
      str += ' ' + zero(i, 2);
    }
  
    //str += '\u001b[0m\n';
    if (buffer.length) str += '\n';
  
    var b = 0;
    var lastBytes;
    var lastSpaces;
    var v;
  
    for (i = 0; i < rows; i++) {
      str += /*'\u001b[36m' +*/ zero(b, offsetLength) + /*'\u001b[0m  '*/ '  ';
      lastBytes = i === rows - 1 ? last : 16;
      lastSpaces = 16 - lastBytes;
  
      var j;
      for (j = 0; j < lastBytes; j++) {
        str += ' ' + zero(buffer[b], 2);
        b++;
      }
  
      for (j = 0; j < lastSpaces; j++) {
        str += '   ';
      }
  
      b -= lastBytes;
      str += '   ';
  
      for (j = 0; j < lastBytes; j++) {
        v = buffer[b];
        str += (v > 31 && v < 127) || v > 159 ? String.fromCharCode(v) : '.';
        b++;
      }
  
      str += '\n';
    }
  
    //process.stdout.write(str);
    console.log(str);
  };
  
new_contents: 'use strict';
  
  var zero = function (n, max) {
    n = n.toString(16).toUpperCase();
    while (n.length < max) {
      n = '0' + n;
    }
    return n;
  };
  
  module.exports = function (buffer) {
    var rows = Math.ceil(buffer.length / 16);
    var last = buffer.length % 16 || 16;
    var offsetLength = buffer.length.toString(16).length;
    if (offsetLength < 6) offsetLength = 6;
  
    var str = 'Offset';
    while (str.length < offsetLength) {
      str += ' ';
    }
  
    str = /*'\u001b[36m' +*/ str + '  ';
  
    var i;
    for (i = 0; i < 16; i++) {
      str += ' ' + zero(i, 2);
    }
  
    //str += '\u001b[0m\n';
    if (buffer.length) str += '\n';
  
    var b = 0;
    var lastBytes;
    var lastSpaces;
    var v;
  
    for (i = 0; i < rows; i++) {
      str += /*'\u001b[36m' +*/ zero(b, offsetLength) + /*'\u001b[0m  '*/ '  ';
      lastBytes = i === rows - 1 ? last : 16;
      lastSpaces = 16 - lastBytes;
  
      var j;
      for (j = 0; j < lastBytes; j++) {
        str += ' ' + zero(buffer[b], 2);
        b++;
      }
  
      for (j = 0; j < lastSpaces; j++) {
        str += '   ';
      }
  
      b -= lastBytes;
      str += '   ';
  
      for (j = 0; j < lastBytes; j++) {
        v = buffer[b];
        str += (v > 31 && v < 127) || v > 159 ? String.fromCharCode(v) : '.';
        b++;
      }
  
      str += '\n';
    }
  
    //process.stdout.write(str);
    //console.log(str);
    return str;
  };
  
subject: Change to return string instead of logging to console