Test case details

Preparation Code

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script> <body> <div class="a"></div> </body>

Test cases

Test #1

$(".a")[0]

Test #2

$(".a").length

Test #3

$('body).hasClass('a')

Test #4

$(".a").size()

Test #5

(document.querySelector('.a') !== null)