This test makes sure that calling checkValidity() on a cloned node does not crash a Debug build. The test passes if there is no crash (and if you don't see any 'FAIL's) On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS element.checkValidity() is true PASS element2.checkValidity() is true PASS element.checkValidity() is true PASS element2.checkValidity() is true PASS element.checkValidity() is true PASS element2.checkValidity() is false PASS element.checkValidity() is true PASS element2.value is "a" PASS element2.checkValidity() is true PASS element2.checkValidity() is true PASS successfullyParsed is true TEST COMPLETE