Bug #8205: Regexp.union behavior and Regexp.try_convert

• Status: Closed
• Assignee: zzak (zzak _)
• Target version: 2.1.0
• ruby -v: 1.9.3p374

[avyy (Alexander Yunin)]

Hi! Why Regexp.union('/../') trying to convert string with directly call rb_check_regexp_type(arg) (re.c:3139) instead of rb_reg_s_try_convert (re.c:3122)? I think second variant would be more correct, and i would be able to rewrite Regexp.try_convert in my code for changing behavior as i need.
For example: i have the code where was implemented String#to_regexp which breaks default behavior of Regexp.union and i got incorrect regexp. But i can't (for some reasons) to rewrite to_regexp method. Yes, stupid example, but it's real situation.

[nagachika (Tomoyuki Chikanaga)]

• Status changed from Open to Feedback

Hello,

Could you show us a reproducive code or a testcase?

[avyy (Alexander Yunin)]

Hello,

Bug description is incorrect, sorry. Now i want to say that implementation of String#to_regexp can breaks behavior of Regexp::union.

class String
def to_regexp
/regexp/
end
end
Regexp.union('/some_regexp/') #=> /regexp/

And it's not documented now.

[nagachika (Tomoyuki Chikanaga)]

• Category set to doc
• Status changed from Feedback to Assigned
• Assignee set to zzak (zzak _)
• Target version set to 2.1.0

Hello, avyy.

That makes sense.
I think it's spec that Regexp.union internally convert arguments with to_regexp, but it is undocumented behavior. I think it's a documentation issue.

[zzak (zzak _)]

• Status changed from Assigned to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r43061.
Alexander, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

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• re.c: [DOC] arguments of Regexp::union receive #to_regexp [Bug #8205]