We have two classes named AttributeAxisIterator, one in package n.s.pmd.lang.ast.xpath and one in n.s.pmd.lang.ast.xpath.saxon. It seems that the second one is resolved to the type of the first one. Try copy pasting the contents of n.s.pmd.lang.ast.xpath.saxon.AttributeAxisIterator in the designer, you'll see that typeof returns the wrong type on the type declaration

• xpath.AttributeAxisIterator
• saxon.AttributeAxisIterator