Drop unused capture group and memoize compiled regex#605
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The outer parentheses around the alternation produced a capturing group whose backreference was never read — preg_match's $matches[0] returns the full match regardless. Switched to (?:...) so PCRE doesn't have to allocate the group. Also added a process-wide static cache for the compiled pattern string, keyed by hash of the pattern list. Repeated `new CrawlerDetect` calls (common in per-request frameworks) now skip the implode of the ~1500-entry crawler list after the first instance. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
Two small changes to
CrawlerDetect::compileRegex:(...), butgetMatches()returns$matches[0]— the full match — so the capturing backreference is never read. Switched to(?:...)so PCRE doesn't allocate the group.md5(serialize($patterns))skips the implode of the ~1500-entry crawler list on everynew CrawlerDetect. Frameworks that instantiate per request (Laravel middleware, etc.) get the win without changing the public API.No behavioural change —
getMatches()still returns the full matched substring.Test plan
vendor/bin/phpunit— 19 tests, 2,274,786 assertions, all pass on PHP 8.4🤖 Generated with Claude Code