Saxon » SaxonJS

I have also created the branch https://github.com/martin-honnen/SaxonJSSchxsltPipelineTest/tree/UseSaxonJS23/SaxonJSSchxsltPipelineTest that uses Saxon-JS 2.3 and where the code works fine and outputs an SVRL report instead of giving that error:

C:\Users\marti\source\repos\SaxonJSSchxsltPipelineTest\SaxonJSSchxsltPipelineTest>node app.js
<?xml version="1.0" encoding="UTF-8"?>
<svrl:schematron-output xmlns:error="https://doi.org/10.5281/zenodo.1495494#error" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:sch="http://purl.oclc.org/dsdl/schematron" xmlns:schxslt-api="https://doi.org/10.5281/zenodo.1495494#api" xmlns:schxslt="https://doi.org/10.5281/zenodo.1495494" xmlns:svrl="http://purl.oclc.org/dsdl/svrl" xmlns:xs="http://www.w3.org/2001/XMLSchema">
   <svrl:metadata xmlns:dct="http://purl.org/dc/terms/" xmlns:skos="http://www.w3.org/2004/02/skos/core#">
      <dct:creator>
         <dct:Agent>
            <skos:prefLabel>Saxon-JS/2.3</skos:prefLabel>
         </dct:Agent>
      </dct:creator>
      <dct:created>2022-05-14T13:24:31.928+02:00</dct:created>
      <dct:source>
         <rdf:Description xmlns:dc="http://purl.org/dc/elements/1.1/">
            <dct:creator>
               <dct:Agent>
                  <skos:prefLabel>SchXslt/1.8.6 Saxon-JS/2.3</skos:prefLabel>
                  <schxslt.compile.typed-variables xmlns="https://doi.org/10.5281/zenodo.1495494#">true</schxslt.compile.typed-variables>
               </dct:Agent>
            </dct:creator>
            <dct:created>2022-05-14T13:24:30.896+02:00</dct:created>
         </rdf:Description>
      </dct:source>
   </svrl:metadata>
   <svrl:active-pattern documents="file:///C:/Users/marti/source/repos/SaxonJSSchxsltPipelineTest/SaxonJSSchxsltPipelineTest/run-pipeline-for-svrl-and-apply-to-schema.sef.json"/>
   <svrl:fired-rule context="root"/>
   <svrl:failed-assert location="/Q{}root[1]" test="@*">
      <svrl:text>root has no attributes.</svrl:text>
   </svrl:failed-assert>
   <svrl:successful-report location="/Q{}root[1]" test=". = 'This is an example.'">
      <svrl:text>root element has value 'This is an example.'</svrl:text>
   </svrl:successful-report>
</svrl:schematron-output>

To see whether the problem only occurs in the context of (a relatively complex code like) Schematron compilation I have now also added some files identity.xsl, identity.sef.json, run-and-apply-identity.js, run-and-apply-identity.xsl, run-and-apply-identity.sef.json and if you run node run-and-apply-identity.js you get the same error with Saxon-JS 2.4 as with the more complex Schematron samples while Saxon-JS 2.3 runs the identity transformation fine.

Well, that is disappointing. I shall investigate and see if we need to do a 2.5.

I think the regression is due to the fix of https://saxonica.plan.io/issues/5039, previously the Saxon-JS code created always a document node, now it might create a document fragment node but the code processing a stylesheet expects a document nodes as at some point it wants to process all top level nodes by processing e.g. stylesheet.documentElement.childNodes, only now, with 2.4, stylesheet can be a document fragment node and document fragment nodes do not have a documentElement at all. That way the attempt to process a stylesheet that is formed as a fragment fails with the attempt to access childNodes on the undefined documentElement of the stylesheet.

If I change a line doing

for (ma = Aa(ha.documentElement.childNodes),
                    y = ma.next(); !y.done; y = ma.next())

to

for (ma = Aa(ha.documentElement ? ha.documentElement.childNodes : ha.childNodes),
                    y = ma.next(); !y.done; y = ma.next())

the Saxon-JS 2.4 code seems to be able to process the stylesheet fine.

I haven't checked whether there is other stylesheet processing code around that tries to process stylesheet.documentElement.childNodes.

I think the fix should rather be

                    for (ma = Aa(ha.documentElement ? ha.documentElement.childNodes : ha.firstElementChild.childNodes),
                    y = ma.next(); !y.done; y = ma.next())

I just tried the following XQuery with Saxon CS 11.3 and Saxon HE 11.3:

transform(map {
  'stylesheet-node' : document { <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="3.0">
    <xsl:mode on-no-match="shallow-copy"/>
    <xsl:template match="/">
      <xsl:next-match/>
      <xsl:comment>Fragment 1</xsl:comment>
    </xsl:template>
  </xsl:stylesheet>,
  <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="3.0">
    <xsl:mode on-no-match="shallow-copy"/>
    <xsl:template match="/">
      <xsl:next-match/>
      <xsl:comment>Fragment 2</xsl:comment>
    </xsl:template>
  </xsl:stylesheet>
  },
  'source-node' : document { <root>test</root> }
})?output

Result: <?xml version="1.0" encoding="UTF-8"?><root>test</root><!--Fragment 1-->

No idea whether that is coincidence or just an accident or quirk but for some reason my suggested fix seems to make Saxon-JS treat a fragment with several top level elements like Saxon Java or CS seem to do, they process the first child element of the fragment as the XSLT stylesheet.

Perhaps it is better to ask Mike what he thinks how a node that is an XDM document node having more than one child element should be treated if used as the stylesheet-node of fn:transform.

Looking at this, I'm wondering what happens if stylesheetNode is the xsl:stylesheet element node?

My reading of the specs (both the XSLT 3.0 spec, §3.6, and the fn:transform spec, is that we should allow a document node containing a single element node, or an element node, but not a document node with multiple element children.

I think both Saxon-JS 2.3 and 2.4 fail on an element node for stylesheet-node in fn:transform when trying to convert the SEF XML to SEF JSON, instead of having the root element of the stylesheet package they process a text node and try to access the .attributes.length of the text node (which should be an element node) and then fail with an error that length of undefined can't be read.

https://github.com/w3c/qt3tests/blob/master/fn/transform.xml doesn't seem to have a test case where an xsl:stylesheet element node instead of a document node is passed to fn:transform.

Added test case fn-transform-7a to pass an xsl:stylesheet element. It passes in SaxonJ 10.x (and therefore presumably 11.x).

Also added -7b and -7c to pass a simplified stylesheet, both as a document node and as an element node.

Also added -7d and -7e to check that the xsl:stylesheet element can be the second child of a document fragment node.