False positives with words blacklist

I have a number of blacklisted words for a field. Among those blacklisted words is the one-character word "r" -- just the letter, without the quotes, e.g.:

ablacklistedword, r, anotherblacklistedword, yetanotherblacklistedword

This results in a false positive when a user enters a multi-character value that contains the letter "r" -- such as "rblahblah" or "blahrblah."

The cause appears to be line 27 of plugins/validator/field_validation_blacklist_validator.inc (in 7.x-2.x-dev):

if ($this->value != '' && (preg_match("/$blacklist_regex/i", $this->value))) {

The preg_match page (http://php.net/manual/en/function.preg-match.php) suggests that this will search $this->value for any occurrence (case insensitive) of each value in the $blacklist_regex array.

To match only the whole string, which I think is the intent (if not maybe this is just a documentation issue), I believe line 26 should be:

$blacklist_regex = '\\b' . implode('\b|\b', $blacklist) . '\\b';

instead of:

$blacklist_regex = implode('|', $blacklist);

That wraps each blacklisted word in '\b' to make it match only on word boundaries.

I can provide a patch if warranted.