[xml] XPath query failing on modified xmlDoc

[Cory Virok <cory dolphtech com>]

Ok, I'm new to libxml2 in general so there's probably a very simple 
solution to this problem, (haven't been able to find it in the archives 
though.)

I have an xml document that I load up and modify. In this particular 
instance, I load the document and then add in a new child element. I 
have verified that the child is in the doc by doing a quick 
xmlDocDump(). After I add children I want to be able to remove them. The 
problem I'm seeing is that when I do an XPath query for the children 
that existed prior to loading the document everything's fine, but when I 
query for the children that I just added I get back an empty node set.

I remake the XPath context using the same doc pointer each time I query 
so I know that the xpath context is using the right doc... It seems like 
the DOM tree hasn't been updated and thus the xpath query cannot find 
the child nodes, but I've verified that the tree is up-to-date...

The only thing I can think of is the format of my xpath expression, 
which does not use explicit '[1]' or 'descendant::' etc...

/config/user-list/user[ nickname="NICKNAME"]

Any help is appreciated.

- Cory Virok