updated for version 7.4.685 Problem: When there are illegal utf-8 characters the old regexp engine may go past the end of a string. Solution: Only advance to the end of the string. (Dominique Pelle)

start:
test for empty string: ok
test for 1 char: ok
test for 3 chars: ok
test for contains meta char: ok
test for contains non-ascii char: ok