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isXMLDoc() - Uncaught TypeError: Cannot read property 'namespaceURI' of undefined #4782
Description
Description
isXMLDoc() throws an error if undefined given, starting from version 3.4.0
Test script:
jQuery.isXMLDoc(undefined)
jQuery 3.3.1 result:
false
jQuery 3.5.1 (currently the latest, but starting from 3.4.0) result:
Uncaught TypeError: Cannot read property 'namespaceURI' of undefined
Techinfo
Before the Sizzle update from 2.3.3 to 2.3.4 (see related commit below), isXML() function looked liked this:
isXML = Sizzle.isXML = function( elem ) {
// documentElement is verified for cases where it doesn't yet exist
// (such as loading iframes in IE - #4833)
var documentElement = elem && (elem.ownerDocument || elem).documentElement;
return documentElement ? documentElement.nodeName !== "HTML" : false;
};
This doesn't throw an error, when the elem is undefined, because it checks it.
In the update from 3.4.0, it looks like this:
isXML = Sizzle.isXML = function( elem ) {
var namespace = elem.namespaceURI,
docElem = ( elem.ownerDocument || elem ).documentElement;
// Support: IE <=8
// Assume HTML when documentElement doesn't yet exist, such as inside loading iframes
// https://bugs.jquery.com/ticket/4833
return !rhtml.test( namespace || docElem && docElem.nodeName || "HTML" );
};
This throws an error when the elem is undefined:
Uncaught TypeError: Cannot read property 'namespaceURI' of undefined
Please, if you can, bring back the previous functionality: undefined is not an XML node, so it should return a false boolean instead of a TypeError.
Thanks in advance!
Additional info
Related commit: d940bc0 (from line 562)
Related blog-post: https://blog.jquery.com/2019/04/10/jquery-3-4-0-released/
Activity
dmethvin commentedon Aug 29, 2020
Can you post a test case showing when this happens? Also can you use the latest jQuery 3 in your test case?
Be aware that version 2.x is no longer supported. If there is a bug to fix we'd only be fixing it in jQuery 3.x, or 4.x if it requires a breaking change.
borzaka commentedon Aug 30, 2020
I'am afraid if I present my use case, the attention will move away from my finding. Which is:
jQuery 3.3.1 returns a different outcome for the same function and argument then 3.5.1
jQuery 3.3.1 returns:
falsejQuery 3.5.1 returns:
Uncaught TypeError: Cannot read property 'namespaceURI' of undefinedFor this line of code:
jQuery.isXMLDoc(undefined)jQuery 3.5.1 doesn't check the argument, 3.3.1 does.
undefinedis not an XML node, so in my interpretation it should returnfalse, as version 3.3.1 does.I'am talking about jQuery 3.x, not 2.x, only 2.x I mentioned is Sizzle update from 2.3.3 to 2.3.4, where this
isXML()function is changed and causing this new TypeError since 3.4.0. Linked under Additional info in my original post.mgol commentedon Aug 30, 2020
As indicated in the signature of that method on its API page, only arguments of Element type are allowed as input to that method. Behavior for all other inputs is undefined as jQuery generally doesn't validate whether input is of a correct type.
If you want to make sure you only use allowed types, using TypeScript with jQuery typings is a good idea.
I'll let it open for discussion for now but generally we've been leaning towards not handling
undefinedinputs in APIs where it's not expected.timmywil commentedon Aug 31, 2020
We're deliberating whether we want to add back the falsey check.
timmywil commentedon Sep 14, 2020
I think we're willing to add back the falsey check, but we'd all feel better if there was a valid use case presented.
Just the opposite btw. It will grant some validity to your finding.
borzaka commentedon Nov 6, 2020
Sorry for the late reply. Here is a part of that code working with ajax responses.
The
$.isXMLDoc(xhr.responseXML)is failing because of the lack of the falsey check as before.Could you reopen this issue please?
mgol commentedon Nov 6, 2020
Thanks for the use case, reopening.
22 remaining items
Selector: Update Sizzle from 2.3.5 to 2.3.6
Selector: Update Sizzle from 2.3.5 to 2.3.6
mgol commentedon Feb 18, 2021
Fixed on
3.x-stable(jQuery 3.x) by #4846.Previously, it was only fixed on
main(jQuery 4.0) by #4814.Closing.
Core: Make jQuery.isXMLDoc accept falsy input
Core: Make jQuery.isXMLDoc accept falsy input
Core: Make jQuery.isXMLDoc accept falsy input
Core: Make jQuery.isXMLDoc accept falsy input
Core: Make jQuery.isXMLDoc accept falsy input
Core: Make jQuery.isXMLDoc accept falsy input
Core: Make jQuery.isXMLDoc accept falsy input
Core: Make jQuery.isXMLDoc accept falsy input
Core: Make jQuery.isXMLDoc accept falsy input