test field is empty
test field is numeric
test field is min. 3 and max. 6 characters long
test fields are identical
test field is a valid email address
test field is plain text
test field is alphabetic (a-z, A-Z)
test field is a digit (0-9)
test field is alphanumeric (a-z, A-z, 0-9)
test fields are a valid password (identical, min. 6, max. 10 characters)
test field is of these values: hello, foo, bar
test field is within a range of 2 - 10
test field is smaller than 5
test field is bigger than 5
test field is of given date format (yyyy-mm-dd) and date is valid