These tests expect FONS0004, but I get XPTY0004.

local-name-from-QName expects an xs:QName.  

Unless I'm mistaken, the argument supplied is an elemStr element whose typed value is an xs:string (not the expected type xs:QName).  Function conversion does not attempt a cast from xs:string to xs:QName, hence FONS0004 is incorrect.

   <test-case name="LocalNameFromQNameFunc021a">
      <description> Test function fn:local-name-from-QName. Conditional expression as parameter where one branch does NOT result in a QName value </description>
      <created by="Mike Rorke" on="2005-09-28"/>
      <modified by="Michael Kay" on="2013-05-01" change="Error code for 3.0. See bug 21723"/>
      <modified by="O'Neil Delpratt" on="2013-06-07" change="Added schemeImport dependency. See bug issue #21238" />
      <environment ref="qname"/>
      <dependency type="spec" value="XP30+ XQ30+"/>
      <dependency type="feature" value="schemaImport"/>
      <test>fn:local-name-from-QName( if( true() ) then (/root/elemStr)[1] else (/root/elemQN)[1] )</test>
      <result>
         <error code="FONS0004"/>
      </result>
   </test-case>