Test for validationMessage IDL attribute for On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". No message PASS testIt("", "", "") is "" Value missing PASS testIt("", "", "") is "Please fill out this field." Type mismatch PASS testIt("foo", "", "") is "" Range overflow PASS testIt("200", "", "100") is "Value must be less than or equal to 100." PASS testIt("200", "", "100.4") is "Value must be less than or equal to 100,4." PASS testIt("200", "", "100") is "Value must be less than or equal to ١٠٠." Range underflow PASS testIt("10", "50", "100") is "Value must be greater than or equal to 50." PASS testIt("10", "50", "100") is "Value must be greater than or equal to ٥٠." Step mismatch PASS testIt("55", "0", "100", "10") is "Please enter a valid value. The two nearest valid values are 50 and 60." Range invalid PASS testIt("10", "100", "50") is "Minimum value (100) must be less than the maximum value (50)." PASS successfullyParsed is true TEST COMPLETE