Function complexity

A stylesheet function containing more than 50 XSLT elements is too complex to read and test. A function should compute one value; when it grows this large it is doing several jobs at once. Break it into smaller functions that each do one thing and call one another.

This check looks only at xsl:function. A large xsl:template is a different smell — it should fan out with apply-templates rather than be split into more functions — and is covered by oversized-template.

Incorrect:

<xsl:function name="my:report" as="xs:string">
  <!-- more than 50 xsl:* descendant elements computing one value -->
</xsl:function>

Correct:

<xsl:function name="my:report" as="xs:string">
  <xsl:sequence select="my:header() || my:body() || my:footer()"/>
</xsl:function>

<xsl:function name="my:header" as="xs:string">
  <!-- ... -->
</xsl:function>