Ensure no double escaping or unescaping in log file parsing

[mountaindude]

Example

The following example shows a pair of hand-written HTML encoding and decoding functions:

module.exports.encode = function(s) {
  return s.replace(/&/g, "&")
          .replace(/"/g, """)
          .replace(/'/g, "'");
};

module.exports.decode = function(s) {
  return s.replace(/&/g, "&")
          .replace(/"/g, "\"")
          .replace(/'/g, "'");
};

The encoding function correctly handles ampersand before the other characters. For example, the string me & "you" is encoded as me & "you", and the string " is encoded as ".

The decoding function, however, incorrectly decodes & into & before handling the other characters. So while it correctly decodes the first example above, it decodes the second example (") to " (a single double quote), which is not correct.

Instead, the decoding function should decode the ampersand last:

module.exports.encode = function(s) {
  return s.replace(/&/g, "&")
          .replace(/"/g, """)
          .replace(/'/g, "'");
};

module.exports.decode = function(s) {
  return s.replace(/"/g, "\"")
          .replace(/'/g, "'")
          .replace(/&/g, "&");
};