Test for bug #680920

Add test cases for the EXSLT func bug

tests/docs/bug-178.xml

+<doc/>

tests/general/Makefile.am

@@ -181,6 +181,7 @@
     bug-171.out bug-171.xsl \
     bug-172.out bug-172.xsl \
     bug-173.out bug-173.xsl \
+    bug-178.out bug-178.xsl \
     character.out character.xsl \
     character2.out character2.xsl \
     itemschoose.out itemschoose.xsl \

tests/general/bug-178.out

+<?xml version="1.0"?>
+<result/>

tests/general/bug-178.xsl

+<xsl:stylesheet
+	xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+	xmlns:func = "http://exslt.org/functions"
+	version="1.0" extension-element-prefixes="func">
+
+<func:function name="func:uaf">
+	<xsl:text/>
+	<func:result/>
+</func:function>
+
+<xsl:template match="/">
+        <result>
+	        <xsl:value-of select="func:uaf()"/>
+        </result>
+</xsl:template>
+
+</xsl:stylesheet>
+