src/etc/testcases/taskdefs/taskdef.xml

<?xml version="1.0"?>

<project name="xxx-test" basedir="." default="test1">

  <target name="test1">
    <taskdef/>
  </target>

  <target name="test2">
    <taskdef name=""/>
  </target>

  <target name="test3">
    <taskdef classname=""/>
  </target>

  <target name="test4">
    <taskdef name="" classname="oops"/>
  </target>

  <target name="test5">
    <taskdef name="test" classname="org.apache.tools.ant.Project" />
  </target>

</project>