To print all assertions from all the testSteps inside a testCase you can use the follow groovy script in a tearDown script of your testCase, it use the getAssertionList() which returns a TestAssertion list, and then iterates over it using label and status property:
testRunner.testCase.testSteps.each{ name,props ->
log.info "Test step name: $name"
// check that the testStep class support assertions
// (for example groovy testStep doesn't)
if(props.metaClass.respondsTo(props, "getAssertionList")){
// get assertionList
props.getAssertionList().each{
log.info "$it.label - $it.status"
}
}
}
Note: Not all kind of testStep's have assertions (e.g Groovy script testStep doesn't) so it's necessary to check it before use getAssertionList())

If you want to get all assertions from one specific testStep you can use the same approach in a groovy script:
// get the testStep
def testStep = testRunner.testCase.getTestStepByName('Test Request')
// check that the testStep specific class support assertions
// (for example groovy testStep doesn't)
if(testStep.metaClass.respondsTo(testStep, "getAssertionList")){
// print assertion names an its status
testStep.getAssertionList().each{
log.info "$it.label - $it.status"
}
}
Hope it helps,
:)- albciff