TestRunListener.afterStep doesn't work

Hi,

I have the following groovy code for the TestRunListener.afterStep event at the project level. I run a testcase but there is no output to the mentioned filepath. I get the error in the log - No signature of method: com.eviware.soapui.impl.wsdl.teststeps.WsdlMessageExchangeTestStepResult.getTestCase() is applicable for argument types....

filePath = "C:/Backup Exclusions/soap"
fos = new FileOutputStream( filePath + testStepResult.testStep.label + '.txt', true )
pw = new PrintWriter( fos )
testStepResult.writeTo( pw )
pw.close()
fos.close()


Can anyone help with getting this to output the text files?

Thanks