Bug #22494: Regexp search misses a match when an assertion precedes a leading .*

• Status: Open
• Assignee: -
• Target version: -
• Backport: 3.3: REQUIRED, 3.4: REQUIRED, 4.0: REQUIRED

[mame (Yusuke Endoh)]

When a regexp starts with an assertion (^, \b, (?=...), (?!...)) followed by .*, the search only tries the start position and misses later matches.

"aab".index(/(?!a).*b/m)       #=> nil (expected: 2)
"ab\ncb".index(/^.*b/m, 1)     #=> nil (expected: 3)
"aaaa bx".index(/\b.*x/, 1)    #=> nil (expected: 4)

@make_now_just (Hiroya Fujinami) found this and wrote the fix.

[mame (Yusuke Endoh)]

• Backport changed from 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN to 3.3: REQUIRED, 3.4: REQUIRED, 4.0: REQUIRED

https://github.com/ruby/ruby/pull/19645