JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
    <head>
        <link rel="stylesheet" href="http://code.jquery.com/qunit/git/qunit.css" type="text/css" media="screen" />
    </head>
    <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>
        <script src="http://code.jquery.com/jquery-latest.js"></script>
        <script type="text/javascript" src="http://code.jquery.com/qunit/git/qunit.js"></script>  
    </body>
</html>

JavaScript

$(document).ready(function() {
    var myFirstCompiler;
    myFirstCompiler = function(str) {
      return ("" + (str || "")).split('').reverse().join('');
    };
    test("a basic test example", function() {
        equal( myFirstCompiler(), "" );
        equal( myFirstCompiler("a"), "a" );
        equal( myFirstCompiler("abc"), "cba" );        
        equal( myFirstCompiler("abc 123"), "321 cba" );                
    });
});