Tests @depends on p:if must not be empty.
Test ab-depends-051.xml is expected to fail with error code err:XS0077
.
<p:declare-step xmlns:err="http://www.w3.org/ns/xproc-error" xmlns:p="http://www.w3.org/ns/xproc" version="3.0">
<p:output port="result"/>
<p:identity>
<p:with-input>
<doc/>
</p:with-input>
</p:identity>
<p:if test="true()" depends="">
<p:identity/>
</p:if>
<p:identity/>
</p:declare-step>
Added new tests for [p:] depends.