From: John Higgins <wishdev@...>
Date: 2011-06-26T12:43:09+09:00
Subject: [ruby-core:37360] [Ruby 1.9 - Bug #4893] Literal Instantiation breaks Object Model


Issue #4893 has been updated by John Higgins.

File strings.rb added

The patch doesn't work....

The 'strings.rb' file I believe is about as simple as we can get. The 'empty_file' attempted to be required in the file is just that - a completely empty file with nothing in it at all.

ruby strings.rb yields

true
strings.rb:10:in `require_relative': method `initialize' called on hidden T_STRING object (0x00000000849f18 flags=0x4c005 klass=0x0) (NotImplementedError)
	from strings.rb:10:in `<main>'

require fails - load works but require is a no go.

----------------------------------------
Bug #4893: Literal Instantiation breaks Object Model
http://redmine.ruby-lang.org/issues/4893

Author: Lazaridis Ilias
Status: Assigned
Priority: Normal
Assignee: Yukihiro Matsumoto
Category: 
Target version: 
ruby -v: 1.9.2


#String2.rb 
class String 
  def initialize(val) 
    self.replace(val) 
    puts object_id 
  end 
  def my_method_test 
    'has method <my_method_test>' 
  end 
end 

# command line 
$ irb 
irb(main):001:0> original = String.new("original") 
=> "original" 
irb(main):002:0> load "String2.rb" 
=> true 
irb(main):003:0> altered = String.new("altered") 
21878604 
=> "altered" 
irb(main):004:0> altered.my_method_test 
=> "has method <my_method_test>" 
irb(main):005:0> literal = "literal" 
=> "literal" 
irb(main):006:0> literal.my_method_test 
=> "has method <my_method_test>" 
irb(main):007:0> 

- 

The initialize method is an integral part of the class String. 
From the moment that "String2.rb" is loaded, the initialize method of 
class String has been validly redefined. 

(The behaviour of the String class within the "irb session" is 
altered) 

The altered initialize method is now an integral part of the class 
String. 

The altered String object behaves as expected (responds to 
"my_method_test, initialized via redefined initialize method). 

The String(Literal) object responds to "my_method_test", but it is was 
not initialized with the redefined initialize method. 

- 

The "Literal Instantiation" calls the original (core-C-level) String 
initialize method instead of the redefined one (user-language-level). 
This *breaks* the object model. 





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