logs are not getting generated correctly when use teardown script

I Got the resolution for my query. The below TearDown script will do the work:

def step_a = "";
for (testStepResult in testRunner.getResults() ) {
def testStep = testStepResult.getTestStep()
step_a = step_a + "TestStep [ " + testStep.name + " ] finished with status " + testStepResult.getStatus().toString() + "\n"
//log.info testStep.testRequest.response.responseHeaders
if (testStep instanceof com.eviware.soapui.model.testsuite.Assertable)
{
for( assertion in testStep.assertionList )
{
def messages = ""
def isAssertionLogged = false
for( message in testStepResult.getMessages() )
{
if(message.contains(assertion.name))
{

messages = messages + testStep.name + "- Error [" + message + "]" + "\n";;
isAssertionLogged = true
break
}
}

if(isAssertionLogged) //if there is no error message for the assertion, the assertion is either passed (VALID) or was not ran (UNKNOWN)
{
step_a = step_a + "Assertion [" + assertion.label + "] has status [FAILED]" + "\n";
step_a = step_a + messages;
}
else {
if(assertion.isDisabled()) {
step_a = step_a + "Assertion [" + assertion.label + "] has status [UNKNOWN]" + "\n"
}
else {
step_a = step_a + "Assertion [" + assertion.label + "] has status [OK]" + "\n"
}
}
}
}
}//end for


log.info "Let’s get Test run results"
File file = new File("C:/Results/TestRunnerStatus20.txt")

file.write step_a