Test for regular expressions with non-character values in them, specifically in character classes. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS "F".match(/[\uD7FF]/) is null PASS "0".match(/[\uD800]/) is null PASS "F".match(/[\uDFFF]/) is null PASS "E".match(/[\uE000]/) is null PASS "y".match(/[\uFDBF]/) is null PASS "y".match(/[\uFDD0]/) is null PASS "y".match(/[\uFDEF]/) is null PASS "y".match(/[\uFDF0]/) is null PASS "y".match(/[\uFEFF]/) is null PASS "y".match(/[\uFEFF]/) is null PASS "y".match(/[\uFFFE]/) is null PASS "y".match(/[\uFFFF]/) is null PASS "y".match(/[\u10FFFF]/) is null PASS "y".match(/[\u110000]/) is null PASS successfullyParsed is true TEST COMPLETE