Issue #19283 has been updated by Sho (Shohei Nakano). This case didn't become error after I tested this regex error case with ruby master branch(https://github.com/ruby/ruby/commit/5abb2ef1532e52f3e5fb63ea25e90a72…. This issue may be resolved by Bug #19273 and PR(https://github.com/ruby/ruby/pull/7035). ---------------------------------------- Bug #19283: Regex error on ruby 3.2 https://bugs.ruby-lang.org/issues/19283#change-101423 * Author: Sho (Shohei Nakano) * Status: Open * Priority: Normal * ruby -v: ruby 3.2.0 (2022-12-25 revision a528908271) [x86_64-linux] * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- There is an regex error pattern on ruby 3.2.0. This pattern is success on ruby 3.1.3. Is this a bug? Or, is ruby 3.2.0 correct? - ruby 3.2.0 ``` # ruby -v ruby 3.2.0 (2022-12-25 revision a528908271) [x86_64-linux] (byebug) MAX_CHAR_LENGTH = 8 8 (byebug) WHITE_SPACE_STR = '[[:space:]]　\uFEFF\u00A0\u200B\u180E' "[[:space:]]　\\uFEFF\\u00A0\\u200B\\u180E" (byebug) r = /\A((.{,#{MAX_CHAR_LENGTH}}x)|(.{,#{MAX_CHAR_LENGTH}}a[#{WHITE_SPACE_STR}]+b.{,#{MAX_CHAR_LENGTH}}))[#{WHITE_SPACE_STR}]*\Z/ix /\A((.{,8}x)|(.{,8}a[[[:space:]]　\uFEFF\u00A0\u200B\u180E]+b.{,8}))[[[:space:]]　\uFEFF\u00A0\u200B\u180E]*\Z/ix (byebug) r.match('a b') #<MatchData "a b" 1:"a b" 2:nil 3:"a b"> (byebug) MAX_CHAR_LENGTH = 9 9 (byebug) r = /\A((.{,#{MAX_CHAR_LENGTH}}x)|(.{,#{MAX_CHAR_LENGTH}}a[#{WHITE_SPACE_STR}]+b.{,#{MAX_CHAR_LENGTH}}))[#{WHITE_SPACE_STR}]*\Z/ix /\A((.{,9}x)|(.{,9}a[[[:space:]]　\uFEFF\u00A0\u200B\u180E]+b.{,9}))[[[:space:]]　\uFEFF\u00A0\u200B\u180E]*\Z/ix (byebug) r.match('a b') nil ``` - ruby 3.1.3 ``` # ruby -v ruby 3.1.3p185 (2022-11-24 revision 1a6b16756e) [x86_64-linux] (byebug) MAX_CHAR_LENGTH = 8 8 (byebug) WHITE_SPACE_STR = '[[:space:]]　\uFEFF\u00A0\u200B\u180E' "[[:space:]]　\\uFEFF\\u00A0\\u200B\\u180E" (byebug) r = /\A((.{,#{MAX_CHAR_LENGTH}}x)|(.{,#{MAX_CHAR_LENGTH}}a[#{WHITE_SPACE_STR}]+b.{,#{MAX_CHAR_LENGTH}}))[#{WHITE_SPACE_STR}]*\Z/ix /\A((.{,8}x)|(.{,8}a[[[:space:]]　\uFEFF\u00A0\u200B\u180E]+b.{,8}))[[[:space:]]　\uFEFF\u00A0\u200B\u180E]*\Z/ix (byebug) r.match('a b') #<MatchData "a b" 1:"a b" 2:nil 3:"a b"> (byebug) MAX_CHAR_LENGTH = 9 9 (byebug) r = /\A((.{,#{MAX_CHAR_LENGTH}}x)|(.{,#{MAX_CHAR_LENGTH}}a[#{WHITE_SPACE_STR}]+b.{,#{MAX_CHAR_LENGTH}}))[#{WHITE_SPACE_STR}]*\Z/ix /\A((.{,9}x)|(.{,9}a[[[:space:]]　\uFEFF\u00A0\u200B\u180E]+b.{,9}))[[[:space:]]　\uFEFF\u00A0\u200B\u180E]*\Z/ix (byebug) r.match('a b') #<MatchData "a b" 1:"a b" 2:nil 3:"a b"> ``` -- https://bugs.ruby-lang.org/