When using $.ajax() for JSONP requests, the "complete" event is fired twice if the JSONP request is from and to the same domain.

You could argue that JSONP shouldn't be used for same-domain JSON requests, but there are circumstances where this does occur for whatever reason, such as in a testing environment where the JSONP resides under the same domain (which may be 'localhost').

This isn't a hard one to reproduce, but here's some sample code anyway...

<script src="jquery-1.3.2.js"></script>

<script>

$.ajax({ type : "GET",

url : <insert url here>,

async : false,

dataType : "json",

complete : function () { alert('complete'); }

});

</script>

Simply replace <insert url here> with a JSONP URL from the same domain the script is run from, and then repeat the test with a JSONP URL from another domain.