exslt features not working in ruby-xslt gem - ruby-on-rails

Question

I have a Rails app and use Bundler to manage gems.
I use the ruby-xslt gem for XSLT transformations.
The gem is not recognizing exslt features like node-set().
Here’s the stylesheet I’ve been testing with
<xsl:stylesheet version="1.1"
xmlns="http://max.gov"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:pre="http://max.gov"
xmlns:exslt="http://exslt.org/common">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<!--The fabricated xml I want to access with exslt:node-set()-->
<xsl:variable name="PRE">
<root>
<item/>
<item/>
</root>
</xsl:variable>
<xsl:template match="/">
<results>
<run1 name="exslt:node-set($PRE)//pre:item">
<results>
<xsl:for-each select="exslt:node-set($PRE)//pre:item">
<success position="{position()}"/>
</xsl:for-each>
</results>
</run1>
<run2 name="exslt:node-set($PRE)//pre:item">
<results>
<xsl:for-each select="exslt:node-set($PRE)//pre:item">
<success position="{position()}"/>
</xsl:for-each>
</results>
</run2>
</results>
</xsl:template>
</xsl:stylesheet>
Here’s output I get when using XML::XSLT in our app:
<?xml version="1.0" encoding="UTF-8"?>
<results xmlns="http://max.gov" xmlns:pre="http://max.gov" xmlns:exslt="http://exslt.org/common">
<run1 name="exslt:node-set($PRE)//pre:item">
<results/>
</run1>
</results>
(Note that not only did the node-set function not work, the element got skipped altogether.)
The code is basically this:
xslt = XML::XSLT.new()
xslt.xml = #xml # #xml string
xslt.xsl = #record.xslt # xslt is stored in db
result = xslt.serve
render :xml => result
Here’s the expected output
<?xml version="1.0" encoding="UTF-8"?>
<results xmlns="http://max.gov" xmlns:pre="http://max.gov" xmlns:exslt="http://exslt.org/common">
<run1 name="exslt:node-set($PRE)//pre:item">
<results>
<success position="1"/>
<success position="2"/>
</results>
</run1>
<run2 name="exslt:node-set($PRE)//pre:item">
<results>
<success position="1"/>
<success position="2"/>
</results>
</run2>
</results>
I get this correct result when doing any of the following…
Run xsltproc from command line
Run the following in the Rails console
xslt = XML::XSLT.new
xslt.xml = File.read('data.xml')
xslt.xsl = File.read('test.xsl')
xslt.serve

Answer 1

We ended up replacing ruby-xslt with Nokogiri and this fixed our problems