.serialize() method adding \r to linebreak?

Question

According to this answer https://stackoverflow.com/a/2115554/2311074 I thought that whether json_encode stores a linebreak as \n or \r\n depends on the operating system. However I discovered today that I can generate both output with json_encode on the same operating system (Ubuntu).

Consider the example

  <form id='form'>
     <textarea id='amd' name='stuff'></textarea>
  </form> 
  <button id='lol'>Press Me</button>

with jQuery

$( document ).ready(function() {
  $('#lol').click(function(){
    var text = $('#amd').val();

    $.ajax({
          type: "POST",
          url: ajax.php,
          data: {stuff: text}
      });
 });

and the following ajax.php

$text = $_POST['stuff'];
file_put_contents('test.txt', json_encode($text));

now entering the following

will write the following content in text.txt

"this is a \nbreak up"

However, if I change the data attribut in the jQUery script to

data: $('#form').serialize()

then I find the following content in the text.txt

"this is a \r\nbreak up"

Why is serialize() generating this additional \r to my linebreak \n? I am not even using windows.

Answer 1

so the answer is very easy. jQuery serialize() is adding \r\n, because it's developers coded it like this. You can see the code in jquery github. They replace all the occurrences of /\r?\n/g with \r\n.