[XALANJ-2430] re-add vector closure

[andreas-ibm]

One of the modifications done in XALANJ-2108 was to remove the vector closure at the start of the resolveDependencies function.

I have re-added the closure and verified it fixes nested variables.

Example stylesheet:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" 
                xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                xmlns:ns1="http://foo/ns1" 
                xmlns:ns2="http://bar/ns2"
                exclude-result-prefixes="ns1 ns2">
  
  <xsl:output method="xml"/>
  
  <xsl:variable name="var1">
    <xsl:variable name="var2">
      <xsl:value-of select="/ns1:outer/ns2:inner"/>
    </xsl:variable>
    <xsl:value-of select="concat('Name:', $var2)"/>
  </xsl:variable>
  
  <xsl:template match="/">
    <Output xmlns="http://baz/ns3">
      <xsl:apply-templates/>
    </Output>
  </xsl:template>
  
  <xsl:template match="ns2:inner">
    <Ns1In>
      <xsl:value-of select="."></xsl:value-of>
    </Ns1In>
    <Ns1Out>
      <xsl:value-of select="$var1"/>
    </Ns1Out>
  </xsl:template>
</xsl:stylesheet>

input message

<ns1:outer xmlns:ns1="http://foo/ns1">
  <ns2:inner xmlns:ns2="http://bar/ns2">InputContent</ns2:inner>
</ns1:outer>

Before the fix this would result in a "circular loop" accusation, and after the loop the result is

<?xml version="1.0" encoding="UTF-8"?><Output xmlns="http://baz/ns3">
        <Ns1In>InputContent</Ns1In><Ns1Out>Name:InputContent</Ns1Out>

I have tested with all the examples in XALANJ-2430 and XALANJ-2108 to ensure I haven't readded the NPE in the latter

[elharo]

This really needs an automated test that exposes the bug.

[andreas-ibm]

I tried, but couldn't figure out how to do it, I read all the docs on testing in xalan and couldn't figure out how to get it working. I have a bunch of changes in my xalan-test workspace, but as far as I can remember (April is a long time ago for me) I couldn't get the tests to run so that they could run on both xalan interpreter and xstlc: