Re: [xml] xmlGetNodePath returning "/(null):data/a:name"

[Daniel Veillard <veillard redhat com>]

On Thu, Dec 18, 2003 at 05:59:03PM -0800, Ralf wrote:
> Hi!
> 
> I'm using libxml2 2.6.3 and trying to get the XPath from a given node
> then later get a nodeset from the expression.
> 
> The XML I'm trying to handle looks like the following, i.e. it has a
> global namespace in the document root and no DTD nor Schema defined:
> <data xmlns="http://something"; xmlns:a="http://another-ns";>
>    <a:name> toto </a:name>
>    <value>2</value>
> </data>
> 
> For the first "name" element, xmlGetNodePath() returns
> "/(null):data/a:name" whereas I was expecting "/data/a:name".

  it's a bug. please bugzilla it.

> xmlXPathEval() fails to return a valid nodeset when receiving
> "/(null):data/a:name" as input.

  yes. Note that xmlXPathEval() will also fail in that example
for "/data/a:name".

> This is not quite the behavior I expected from xmlGetNodePath(); I
> haven't found anything in the FAQs or bugs related to this behavior.
> Line 4159 of tree.c simply uses cur->ns->prefix in snprintf without
> checking if prefix is NULL before. Changing the test to "if (cur->ns &&
> cur->ns->prefix) {" will make xmlGetNodePath return what I expect, but
> xmlXPathEval() still fails to return a valid nodeset (so does xmllint or
> testXPath when I provide the XPath I want).

  that's normal.

> So, is my understanding of XPath with a default global namespace wrong,

  right you're wrong. /data will not select elements with a namespace.
It's an XPath FAQ .

Daniel

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