Schematron validation erroneously fails with missing namespace exception

[ujay68]

Strange effect: When I use the runnable jing.jar v20181222 or the runnable jing.jar built with Ant from the current head (commit 12275d1) on the attached Schematron schema and test.xml, I get this exception:

ERROR:  'Namespace for prefix 't' has not been declared.'
fatal: exception "java.lang.RuntimeException" thrown: Namespace for prefix 't' has not been declared.

To me, the schema looks ok. I've tried to hunt this down with a development setup in an IDE (IntelliJ IDEA), but when I run the current head code from within the IDE, the xml file validates just fine.

Maybe something to do with a resource missing from the jar but found by the IDE? Any idea what might be wrong here?

test.sch.txt
test.xml.txt

[ujay68]

The difference seems to be in the XSLT implementation, depending on whether Saxon is in the classpath or not. The method com.thaiopensource.validate.schematron.ISOSchemaReaderImpl#createSchema uses these implementations (AdoptOpenJDK build 1.8.0_242-b08 on macOS):

With Saxon in the classpath:

• XMLReader: com.icl.saxon.aelfred.SAXDriver
• TemplatesHandler: com.icl.saxon.TemplatesHandlerImpl

Without Saxon in the classpath:

• XMLReader: com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser
• TemplatesHandler: com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesHandlerImpl

The Xalan XSLT compiler runs into an ER_NAMESPACE_PREFIX exception somewhere deep in its stack (GregorSamsa in between). So, one of these countless bugs in JDK's repackaged Xalan probably.