Issue #20098 has been reported by tompng (tomoya ishida). ---------------------------------------- Bug #20098: Wrong regexp match in ruby 3.2 and 3.3 https://bugs.ruby-lang.org/issues/20098 * Author: tompng (tomoya ishida) * Status: Open * Priority: Normal * ruby -v: ruby 3.3.0 (2023-12-25 revision 5124f9ac75) +MN [arm64-darwin22] * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- These regexp all matches in ruby 3.1.4, but not in ruby 3.3.0. ~~~ruby p /a((.|.)|bc){,4}z/.match? 'abcbcbcbcz' p /a(b+?c*){4,5}z/.match? 'abbbccbbbccbcbcz' # matches in ruby 3.2.2 p /a(b+?(.|.)){2,3}z/.match? 'abbbcbbbcbbbcz' p /a(b*?(.|.)[bc]){2,5}z/.match? 'abcbbbcbcccbcz' ~~~ Adding backref (to disable optimization) makes them match. ~~~ruby p /()\1a((.|.)|bc){,4}z/.match? 'abcbcbcbcz' p /()\1a(b+?c*){4,5}z/.match? 'abbbccbbbccbcbcz' p /()\1a(b+?(.|.)){2,3}z/.match? 'abbbcbbbcbbbcz' p /()\1a(b*?(.|.)[bc]){2,5}z/.match? 'abcbbbcbcccbcz' ~~~ Found in this script https://gist.github.com/tompng/aa0706a181e9187bd79e8cec5a5f3c97 -- https://bugs.ruby-lang.org/