[xsl] Stylesheet works in oXygen fails in Python with Saxonc

["dvint@xxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

I have a stylesheet that works fine in oXygen and Python using 
lxml/etree. I'm experimenting with switching the Pythion config over to 
Saxon. Currently I'm just testing a simple Python config to run the 
stylesheet as follows:

from saxonche import *

with PySaxonProcessor(license=False) as proc:
     print(proc.version)
     xsltproc = proc.new_xslt30_processor()
     executable = 
xsltproc.compile_stylesheet(stylesheet_file="02a-build_content-short.xslt")
     executable.set_result_as_raw_value(True)
     executable.set_initial_match_selection(file_name="nav-short.xml")
     result = executable.apply_templates_returning_string()
     print(result)

Attached are the xaml and XSLT files and I'm getting these errors:

(base) danvint@mac-PHFW3L52 samples % python3 
/Users/danvint/pubsrc/adoc2PDF/_saxon-test.py
SaxonC-HE 12.5 from Saxonica
Error at char 9 in expression in xsl:variable/@select on line 13 column 
62 of 02a-build_content-short.xslt:
   XPDY0002  Finding root of tree: the context item is absent. Found 
while atomizing the
   first argument of fn:concat() in {((root/nav)/div[xs:string(@class) eq
   "toc"])/@home-folder[1]} on line 13
In variable FILEPATH on line 13 column 62 of 
02a-build_content-short.xslt:
      invoked by global variable FILEPATH at 
file:///Users/danvint/pubsrc/adoc2PDF/02a-build_content-short.xslt#13
During lazy evaluation of fn:concat(...) on line 43 of 
file:///Users/danvint/pubsrc/adoc2PDF/02a-build_content-short.xslt
   In template rule with match="a" on line 36 of 
02a-build_content-short.xslt
      invoked by built-in template rule (text-only)
   In template rule with match="span[fn:contains(...)]" on line 26 of 
02a-build_content-short.xslt
      invoked by built-in template rule (text-only)
   In template rule with match="span[fn:contains(...)]" on line 26 of 
02a-build_content-short.xslt
      invoked by built-in template rule (text-only)
   In template rule with match="h3" on line 24 of 
02a-build_content-short.xslt
      invoked by built-in template rule (text-only)
   In template rule with match="h3" on line 24 of 
02a-build_content-short.xslt
      invoked by built-in template rule (text-only)
   In template rule with match="h3" on line 24 of 
02a-build_content-short.xslt
      invoked by built-in template rule (text-only)
   In template rule with match="h3" on line 24 of 
02a-build_content-short.xslt
      invoked by built-in template rule (text-only)
   In template rule with match="/" on line 18 of 
02a-build_content-short.xslt
      invoked by xsl:apply-templates at 
file:///Users/danvint/pubsrc/adoc2PDF/02a-build_content-short.xslt#20
   In template rule with match="/" on line 18 of 
02a-build_content-short.xslt
Traceback (most recent call last):
   File "/Users/danvint/pubsrc/adoc2PDF/_saxon-test.py", line 10, in 
<module>
     result = executable.apply_templates_returning_string()
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   File "python_saxon/saxonc.pyx", line 2405, in 
saxonche.PyXsltExecutable.apply_templates_returning_string
saxonche.PySaxonApiError: XPDY0002: Finding root of tree: the context 
item is absent. Found while atomizing the first argument of fn:concat() 
in {((root/nav)/div[xs:string(@class) eq "toc"])/@home-folder[1]} on 
line 13. Line number: 13


..dan
<nav>
	<div class="coverpage">
		<div class="doctitle"> FORMAT: sample 2.1 _Early Access CONTENT </div>
		<div class="publicationdate"> January 08, 2025 </div>
		<div class="productname"> FORMAT: sample 2.1 _Early Access CONTENT </div>
		<span class="productversion"> latest </span>
		<img class="logo"
			src="/Users/danvint/pubsrc/adoc2PDF/PIC_square_logo_PIC_red_RGB.png"
		/>
	</div>
	<div class="toc"
		home-folder="/Users/danvint/_stash/format-sample-work/target/build/site/FormatSample-samples2/_pdf_build/simple_element_samples">
		<h3> Table of Contents </h3>
		<div class="toc_content">
			<div class="wholetoc">
				<ul class="nav-list">
					<li class="nav-item" data-depth="1">
						<span class="nav-text nav-item-toggle"> Simple Element
							Samples </span>
						<ul class="nav-list">
							<li class="nav-item is-current-page" data-depth="2">
								<a class="nav-link" entry-type="file"
									filename="fs_concept_examples.html"
									href="fs_concept_examples.html"
									id="idp105548782269128"> FORMAT: Concept
									topic examples </a>
							</li>
						</ul>
					</li>
				</ul>
			</div>
		</div>
	</div>
</nav>

[demime 1.01d removed an attachment of type text/xml which had a name of 02a-build_content-short.xslt]