Bug 29357 – Web Inspector: Errors When Displaying XPathResult Information

• Status: UNCONFIRMED
• Component: Web Inspector

[Joseph Pecoraro]

Steps to Reproduce:
1. Evaluate the following in the Console of the Inspector on any web  page:
document.evaluate("//*", document, null, XPathResult.ANY_TYPE, null);
2. Attempt to Expand the Object Tree that appears in the Console.

Expected Results:
I'd like to see the properties of the XPathResult. The following was generated using keys():
["resultType", "stringValue", "booleanValue", ... ]

Actual Results:
- A log message (not an error message) saying "Error dispatching: getProperties"
- A blank error message shows up in the inspector's inspector

Further Issues:
- works => keys( document.evaluate(...) ); 
- doesn't work -> values( document.evaluate(...) );
- trying to access "snapshotLength" or "snapshotItem" and probably other values results in a DOM Exception.  Are there problems with XPath in general?

[Alexey Proskuryakov]

> - trying to access "snapshotLength" or "snapshotItem" and probably other values
> results in a DOM Exception.  Are there problems with XPath in general?

XPathResult.ANY_TYPE gives an UNORDERED_NODE_ITERATOR_TYPE result, so snapshot-related accessors can't work. You need to pass a desired result type explicitly for them to work.

This change doesn't make visual inspection work though - I guess custom code will need to be written for presenting XPathResult.

[Radar WebKit Bug Importer]

<rdar://problem/19281526>