Too Long; Didn't Read
Regular expressions are a powerful mechanism for matching patterns in strings. But matching a pattern may - depending on the pattern - require stack space proportional to the length of the input. This means large inputs could cause the program to crash with a stack overflowException. To prevent this, we have a rule that warns you about issues like this: Regular expressions should not overflow the stack. The rule tries to estimate how much stack space a regular expression will consume relative to the input size. It only raises issues on regular expressions whose stack consumption exceeds a configurable threshold.