JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://code.jquery.com/qunit/qunit-git.js"></script>
<link rel="stylesheet" href="http://code.jquery.com/qunit/qunit-git.css">
<body>
  <h1 id="qunit-header">QUnit example</h1>
 <h2 id="qunit-banner"></h2>
 <div id="qunit-testrunner-toolbar"></div>
 <h2 id="qunit-userAgent"></h2>
 <ol id="qunit-tests"></ol>
 <div id="qunit-fixture">test markup, will be hidden</div>
</body>

JavaScript

function process(lst) {
    for (var i=0;i<lst.length;i++) {
        lst[i] = lst[i]*2;
    }        
    return lst;
}    

var ret_list = jQuery.map([[1,2,3],[4,5,6],[7,8,9]],function(item) { return process(item)});
var expected_result = [[2,4,6],[8,10,12],[14,16,18]];
var flattened_result = [2,4,6,8,10,12,14,16,18];

module("jQuery.map test");
test("Test to check expected behaviour", function() {
  expect(1);
  deepEqual(ret_list,expected_result);
});

test("Test to show current behaviour", function() {
  expect(1);   
  deepEqual(ret_list,flattened_result);
});