It happens with IE7 (IEtester v. 0.4.8) at this line

id = isNode ? elem[ internalKey ] : elem[ internalKey ] && internalKey

when accessing elem[internalKey].

It seems no elem property is accessible. I detected the error happening when elem is the whole DOMWindow object containing many functions and ajax calls but I wasn't able to isolate the problem. Every other elem in the page doesn't seem to raise exceptions. I added the following workaround to the jquery code

var privateCache, thisCache, ret,

internalKey = jQuery.expando, getByName = typeof name === "string",

We have to handle DOM nodes and JS objects differently because IE6-7 can't GC object references properly across the DOM-JS boundary isNode = elem.nodeType,

Only DOM nodes need the global jQuery cache; JS object data is attached directly to the object so GC can occur automatically cache = isNode ? jQuery.cache : elem,

Only defining an ID for JS objects if its cache already exists allows the code to shortcut on the same path as a DOM node with no cache id = isNode ? elem[ internalKey ] : elem[ internalKey ] && internalKey, isEvents = name === "events";

try {

var id = isNode ? elem[ internalKey ] : elem[ internalKey ] && internalKey;

} catch(e) {

do nothing

}

The following code works in 1.3.1 and doesn't in 1.3.2.

As suggested ​here, QUnit could be extended with a raises assertion to test for the occurrence of exceptions.

The attached patch allows writing tests like the following:

var expression, expected;

// should pass
expression = function() { return foo.bar; };
expected = "TypeError";
throwsEx(expression, expected, "invalid property access raises
TypeError exception");

// should fail
expression = function() { var foo = {}; return foo.bar; };
expected = "NoneError";
throwsEx(expression, expected, "property access raises NoneError
exception");

(Note that these tests use closures to wrap around the expressions which are actually being tested.)