Forum: Ruby-core [ruby-trunk - Bug #7842][Assigned] An alias of a "prepend"ed method skips the original method when c

Issue #7842 has been reported by mame (Yusuke Endoh).

----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee: matz (Yukihiro Matsumoto)
Category:
Target version: next minor
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>

Issue #7842 has been updated by marcandre (Marc-Andre Lafortune).


I agree, this can only be a bug.
----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842#change-36252

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee: matz (Yukihiro Matsumoto)
Category:
Target version: next minor
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>

Issue #7842 has been updated by nobu (Nobuyoshi Nakada).


Rather I expect [B, A] in this case.
----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842#change-36275

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee: matz (Yukihiro Matsumoto)
Category:
Target version: next minor
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>

(2013/02/14 16:14), nobu (Nobuyoshi Nakada) wrote:
>
> Rather I expect [B, A] in this case.

+1

> Rather I expect [B, A] in this case.

Fine.  I just wanted to point out the weird skipping.
(Actually, I expect nothing for such a code :-)


2013/2/14, SASADA Koichi <ko1@atdot.net>:

Issue #7842 has been updated by marcandre (Marc-Andre Lafortune).


nobu (Nobuyoshi Nakada) wrote:
> Rather I expect [B, A] in this case.

You do?

There would be no way to safely monkey patch this method without using 
Prepend! So any 1.9.x library that uses monkey patching like 
alias_method_chain could be incompatible with prepended classes!

I expect:
  B.instance_method(:m) == B.instance_method(:m2) # => true in rc2, 
false in trunk, should be true
  B.new.m2 # => [P, B, A], since they are aliases appart from their name

Here is another bug (even more clear) that might be related:
  B.instance_method(:m).owner # => P in rc2 (ok), B in trunk (not ok)
  B.instance_method(:m2).owner # => #<B:0x0000010384b418>, should be P

I wish I had time to look at it further.
----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842#change-36292

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee: matz (Yukihiro Matsumoto)
Category:
Target version: next minor
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>

Issue #7842 has been updated by matz (Yukihiro Matsumoto).


I expect:

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    alias m2 m
    prepend P
    alias m3 m
  end
  B.new.m2
    #=> expected: B, A
  B.new.m3
    #=> expected: P, B, A

Matz.

----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842#change-36443

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee: matz (Yukihiro Matsumoto)
Category:
Target version: next minor
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>

I'm sorry, but this ticket confuses me. Why does "A" ever get output, if
B#m does not also call super?

Issue #7842 has been updated by marcandre (Marc-Andre Lafortune).

Category set to core
Assignee deleted (matz (Yukihiro Matsumoto))


----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842#change-36485

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee:
Category: core
Target version: next minor
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>

Issue #7842 has been updated by marcandre (Marc-Andre Lafortune).


phluid61 (Matthew Kerwin) wrote:
> I'm sorry, but this ticket confuses me. Why does "A" ever get output, if
>  B#m does not also call super?

You're right to be confused, there's a missing `super` in the examples 
that everyone assumed was there.

So here's the corrected version:

    module P
      def m; puts "P"; super; end
    end
    class A
      def m; puts "A"; end
    end
    class B < A
      def m; puts "B"; super; end
      alias m2 m
      prepend P
      alias m3 m
    end

    B.new.m2 #=> expected: B, A
    B.new.m3 #=> expected: P, B, A


----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842#change-36484

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee: matz (Yukihiro Matsumoto)
Category:
Target version: next minor
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>

Issue #7842 has been updated by ko1 (Koichi Sasada).

Assignee set to nobu (Nobuyoshi Nakada)
Target version changed from next minor to 2.1.0

marcandre: why you remove assignee?
you mean specification discussion was finished at [ruby-core:52386]#5?
I assume the reason and I assign this ticket nobu, the patch monster.

----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842#change-36729

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee: nobu (Nobuyoshi Nakada)
Category: core
Target version: 2.1.0
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>

Issue #7842 has been updated by marcandre (Marc-Andre Lafortune).


ko1 (Koichi Sasada) wrote:
> marcandre: why you remove assignee?
> you mean specification discussion was finished at [ruby-core:52386]#5?
> I assume the reason and I assign this ticket nobu, the patch monster.

Exactly.

----------------------------------------
Bug #7842: An alias of a "prepend"ed method skips the original method 
when calling super
https://bugs.ruby-lang.org/issues/7842#change-36755

Author: mame (Yusuke Endoh)
Status: Assigned
Priority: Normal
Assignee: nobu (Nobuyoshi Nakada)
Category: core
Target version: 2.1.0
ruby -v: ruby 2.0.0dev (2013-02-13 trunk 39225) [x86_64-linux]


Hello,

  module P
    def m; puts "P"; super; end
  end
  class A
    def m; puts "A"; end
  end
  class B < A
    def m; puts "B"; end
    prepend P
    alias m2 m
  end
  B.new.m2
    #=> expected: P, B, A
    #=> actual:   P, A

Is this intentional?
It looks weird to me that calling super of P#m (as m2) skips A#m.

--
Yusuke Endoh <mame@tsg.ne.jp>