unparsed-text-available() in an XSLT step throws an error

[gimsieke]

When I run

<p:declare-step 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
  xmlns:p="http://www.w3.org/ns/xproc" 
  version="1.0" name="bug">
  <p:output port="result" primary="true"/>
  <p:xslt name="xslt" template-name="main">
    <p:input port="source"><p:empty/></p:input>
    <p:input port="stylesheet">
      <p:inline>
        <xsl:stylesheet version="2.0">
          <xsl:template name="main">
            <result>
              <doc-available>
                <xsl:sequence select="doc-available('non-existing.xml')"/>
              </doc-available>
              <unparsed-text-available>
                <xsl:sequence 
                  select="unparsed-text-available('non-existing.txt')"/>  
              </unparsed-text-available>
            </result>
          </xsl:template>
        </xsl:stylesheet>
      </p:inline>
    </p:input>
    <p:input port="parameters"><p:empty/></p:input>
  </p:xslt>
</p:declare-step>

Calabash 1.0.9 terminates with a java.io.FileNotFoundException, complaining about 'non-existing.txt' not being there.

This example works as expected in 1.0.3:

<result>
  <doc-available>false</doc-available>
  <unparsed-text-available>false</unparsed-text-available>
</result>

Please note that doc-available() still works.

I didn’t check with which Calabash version it ceased to work. I did check that it happens on Linux and Windows with Saxon HE 9.4.0.4, 9.4.0.6, and EE 9.4.0.7.