Problem with XLST identity and JRuby, https://github.com/sparklemotion/nokogiri/issues/954

xslt-jruby.rb

#!/usr/bin/env ruby

require 'nokogiri'

doc = Nokogiri::XML(%q{
<doc>
	<sp id="sp1">
		<speaker>Second</speaker>
		<l n='5'>a</l>
		<l n='8'>a</l>

		<pb n='2'/>
	</sp>

	<sp id="sp2">
		<!-- if you remove this element no spurios text will be generated-->
		<speaker>Third</speaker>
		<l n='9'>a</l>
		<l n='10'>a</l>

		<pb n='3'>
	</sp>
</doc>
})

xslt = Nokogiri::XSLT(DATA.read)

portion = xslt.transform(doc)

puts portion.to_xml

puts "is text empty? it should be..."
text = portion.text.strip
p text.empty? #=> should be true
p text #=> in JRuby it prints "doc>"

__END__
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
	<xsl:template match="*">
		<xsl:variable name="has" select='boolean(.//*[name()="pb" and @n="2"])'/>

		<xsl:variable name="is" select='name()="pb" and @n="2"'/>

		<xsl:if test="$has or $is">
			<xsl:copy>
				<xsl:apply-templates select="*|@*|text()"/>
			</xsl:copy>
		</xsl:if>
	</xsl:template>

	<xsl:template match="@*|text()">
		<xsl:copy/>
	</xsl:template>
</xsl:stylesheet>