From: "David A. Black" <dblack@...>
Date: 2008-10-11T03:14:57+09:00
Subject: [ruby-core:19288] Re: [Bug #632] StringIO has an odd alias implementation [?]

Hi --

On Sat, 11 Oct 2008, Roger Pack wrote:

> Bug #632: StringIO has an odd alias implementation [?]
> http://redmine.ruby-lang.org/issues/show/632
>
> Author: Roger Pack
> Status: Open, Priority: Normal
>
> Here's my situation:
>
> require 'stringio'
> class C < StringIO
> alias :old_init :initialize
> def initialize
>   old_init
> end
> end
> C.new # fails 1.9, succeeds 1.8.6
>
> normal classes:
>
> class A
> def initialize
>   print 'A init'
> end
> end
> class B < A
> alias :old_init :initialize
> def initialize
>   old_init
> end
> end
> B.new # succeeds 1.9, 1.8

I believe it's because of this:

static VALUE
strio_initialize(int argc, VALUE *argv, VALUE self)
{
     struct StringIO *ptr = check_strio(self);

     if (!ptr) {
         DATA_PTR(self) = ptr = strio_alloc();
     }
     rb_call_super(0, 0);                      /* Specifically, this */
     strio_init(argc, argv, ptr);
     return self;
}

Note that the error is coming from old_init:

sio.rb:6:in `old_init': undefined method `old_init' for #<C:0x1e62e8>
(NoMethodError)

So it's running strio_initialize under the name old_init and therefore
unable to find a super version of it.


David

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