Existence tests for .setCustomValidity property On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". Existence of .setCustomValidity PASS typeof document.getElementsByTagName("input")[0].setCustomValidity is "function" PASS typeof document.getElementsByTagName("button")[0].setCustomValidity is "function" PASS typeof document.getElementsByTagName("fieldset")[0].setCustomValidity is "function" PASS typeof document.getElementsByTagName("select")[0].setCustomValidity is "function" PASS typeof document.getElementsByTagName("textarea")[0].setCustomValidity is "function" PASS typeof document.getElementsByTagName("output")[0].setCustomValidity is "function" PASS typeof document.getElementsByTagName("object")[0].setCustomValidity is "function" PASS typeof document.getElementsByTagName("keygen")[0].setCustomValidity is "function" PASS successfullyParsed is true TEST COMPLETE Test