When loading a test plan which has an "XPath Assertion" element, it seems the XPath string (there is no label for it in the GUI, it's the text box to the left of the "Validate" button) is always set to "/". More importantly however, It seems that nothing that is typed into this text box takes effect. I added a System.out.println statement to line 122 of XPathAssertion.java in order to see the value of "getXPathString()", and it was "/" even though I had typed a different expression into the text field. This is my first ever Bugzilla report, so please be gentle in your admonishment of me if I have not filled in this form correctly :-)
I have added System.out.println() statements to XPathAssertion.java, XPathAssertionGui.java, and XPathPanel.java to try to help track this down. In all cases when I print the value of the XPath expression it is the default: "/". I don't know if that helps, but _to me_ it looks like the value of the xpath expression is never being read from the text box.
It is being read from the text box - however the text box on screen is not the one that it is being read! Fixed in CVS (HEAD)
*** Bug 37163 has been marked as a duplicate of this bug. ***
This issue has been migrated to GitHub: https://github.com/apache/jmeter/issues/1532