XSLTParseError for xsl:template inside XIncluded .xml file is silent

When an XSLTParseError occurs in an xsl:template inside an XIncluded .xml file, the error is not shown.

Usecase:
-----------
rules.xml:
   <xi:include href="python:rules_base.xml" />

rules_base.xml:
    <xsl:template css:match="dt.portletHeader.hiddenStructure">
        <xsl:attribute name="class">
            <xsl:value-of select='replace(., "hiddenStructure", "")'/>
        </xsl:attribute>
    </xsl:template>

Expected:
  An XSLTParseError.

Actual:
  Nothing.