Issue #8210 has been updated by k_takata (Ken Takata).


I think it's better to backport this patch to Ruby 1.9.3 too.
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Backport #8210: Multibyte character interfering with end-line character within a regex
https://bugs.ruby-lang.org/issues/8210#change-38516

Author: sawa (Tsuyoshi Sawada)
Status: Assigned
Priority: Normal
Assignee: nagachika (Tomoyuki Chikanaga)
Category: 
Target version: 


=begin
With this regex:

    regex1 = /\z/

the following strings match as expected:

    "hello" =~ regex1 # => 5
    "????????лу?бу??" =~ regex1 # => 5

but with these regexes:

    regex2 = /#$/?\z/
    regex3 = /\n?\z/

they show difference:

    "hello" =~ regex2 # => 5
    "hello" =~ regex3 # => 5
    "????????лу?бу??" =~ regex2 # => nil
    "????????лу?бу??" =~ regex3 # => nil

The string encoding is UTF-8, and the OS is Linux (i.e., `$/` is `"\n"`). I expect them to behave the same, and believe this is a bug.
=end


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