Backport #8238: Prepending any module to DateTime causes infiinite loop when using zone-related methods

• Status: Closed
• Assignee: nagachika (Tomoyuki Chikanaga)

[mjtko (Mark Titorenko)]

Prepending a Module to DateTime and then inspecting or trying to use any of the methods associated with the timezone causes what appears to be an inifinite loop.

The following code demonstrates the issue:

require 'date'
DateTime.instance_eval { prepend Module.new }
DateTime.now.offset

A cursory inspection shows that similar results (or lack of!) are yielded from #zone, #hour, #minute etc. though #year, #month and #day appear unaffected:

2.0.0p0 :001 > require 'date'
=> true
2.0.0p0 :002 > DateTime.instance_eval { prepend Module.new }
=> DateTime
2.0.0p0 :003 > d = DateTime.now; nil
=> nil
2.0.0p0 :004 > d.year
=> 2013
2.0.0p0 :005 > d.month
=> 4
2.0.0p0 :006 > d.day
=> 8
2.0.0p0 :007 > d.minute
^C

[nagachika (Tomoyuki Chikanaga)]

• Category set to core
• Status changed from Open to Assigned
• Assignee set to nobu (Nobuyoshi Nakada)
• Priority changed from Normal to 5

Hello, Mark
Thank you for your reporting.

I can reproduce it with trunk(r40190) and 2.0.0-dev(patchlevel 120) and wrote smaller reproducive code. It is not an issue of Date/DateTime but method search.

class A
def m
end
private :m
end

class B < A
public :m
prepend Module.new
end

B.new.m

[mjtko (Mark Titorenko)]

nagachika san

Thank you for your further diagnosis of this problem. A method search issue certainly sounds like it warrants a High priority! I am working around my particular instance of this problem by falling back to an include approach for now.

Cheers,

Mark.

[naruse (Yui NARUSE)]

• Target version set to 2.1.0

[nobu (Nobuyoshi Nakada)]

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

This issue was solved with changeset r42724.
Mark, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

vm_insnhelper.c: fix zsuper in prepended

• vm_insnhelper.c (vm_call_method): a method entry refers the based
  class/module, so should search superclass from the origin i-class
  where the entry belongs to, to get rid of infinite loop when zsuper
  in a prepended class/module. [ruby-core:54105] [Bug #8238]

[nagachika (Tomoyuki Chikanaga)]

• Tracker changed from Bug to Backport
• Project changed from Ruby master to Backport200
• Category deleted (core)
• Status changed from Closed to Assigned
• Assignee changed from nobu (Nobuyoshi Nakada) to nagachika (Tomoyuki Chikanaga)
• Target version deleted (2.1.0)

[nagachika (Tomoyuki Chikanaga)]

• Status changed from Assigned to Closed

This issue was solved with changeset r42726.
Mark, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

merge revision(s) 42724: [Backport #8238]

* vm_insnhelper.c (vm_call_method): a method entry refers the based
  class/module, so should search superclass from the origin i-class
  where the entry belongs to, to get rid of infinite loop when zsuper
  in a prepended class/module.  [ruby-core:54105] [Bug #8238]