From: Mauricio Fernandez <mfp@...>
Date: 2007-04-26T18:45:34+09:00
Subject: Re: [patch] Re: test/unit inconsistencies between 1.9 and 1.8

On Thu, Apr 26, 2007 at 03:56:25PM +0900, Adam Bozanich wrote:
> I located the problem, below is a small patch ( copy & paste from 
> 1.8sources ).
> 
> It appears that a block/proc with no arguments has arity -1.
> 
> irb(main):001:0> proc { }.arity
> => -1
> irb(main):002:0> proc {|| }.arity
> => -1
>
> and that somebody forgot about that below.
> 
> -Adam
> 
> Index: lib/test/unit/testcase.rb
> ===================================================================
> --- lib/test/unit/testcase.rb   (revision 12221)
> +++ lib/test/unit/testcase.rb   (working copy)
[...]

?
AFAIK #arity was redefined in 1.9 to return 0 for Procs with no arguments.
That patch was applied to 1.8 three years ago but it's not supposed to be
needed on 1.9, see [ruby-core:2829].

Also,

RUBY_VERSION                                       # => "1.9.0"
RUBY_RELEASE_DATE                                  # => "2007-02-07"
proc{}.arity                                       # => 0
proc{||}.arity                                     # => 0
Proc.new{}.arity                                   # => 0
require 'test/unit'
class TC < Test::Unit::TestCase
  define_method("test_foo"){ assert true }
end
# >> Loaded suite -
# >> Started
# >> .
# >> Finished in 0.001363 seconds.
# >> 
# >> 1 tests, 1 assertions, 0 failures, 0 errors

I can't see any recent reference to arity in the Changelog, and
proc_arity is identical to the one in my build:
http://svn.ruby-lang.org/cgi-bin/viewvc.cgi/trunk/proc.c?revision=12212&view=markup

Has this really changed in the last couple months? If so, there's a bug,
either in the Rdoc documentation or the code.

-- 
Mauricio Fernandez  -   http://eigenclass.org   -  singular Ruby
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