method-missing.txt

$ cat t.rb
require 'rubygems'

gem 'mocha-macruby', '0.9.8.20100129120100'
#gem 'mocha-macruby', '0.9.9.20101102121900'
require 'mocha'

require 'bacon'
require 'mocha-on-bacon'

Bacon.summary_on_exit

describe "Mocha on MacRuby" do
  it "overrides native objc methods" do
    m = mock('foo')
    m.expects(:init).returns(m)
    m.init
  end
end

$ macruby t.rb
Mocha on MacRuby
- overrides native objc methods [ERROR: RuntimeError]

RuntimeError: cannot undefine method `init' because it is a native method
	/Library/Frameworks/MacRuby.framework/Versions/0.8/usr/lib/ruby/Gems/1.9.2/gems/mocha-on-bacon-0.1.1/lib/mocha-on-bacon.rb:17:in `it:': Mocha on MacRuby - overrides native objc methods
	/Users/eloy/code/MacRuby/mocha/t.rb:13:in `block'
	/Users/eloy/code/MacRuby/mocha/t.rb:12:in `<main>'

1 specifications (0 requirements), 0 failures, 1 errors

override.txt

$ cat t.rb    
require 'rubygems'

#gem 'mocha-macruby', '0.9.8.20100129120100'
gem 'mocha-macruby', '0.9.9.20101102121900'
require 'mocha'

require 'bacon'
require 'mocha-on-bacon'

Bacon.summary_on_exit

describe "Mocha on MacRuby" do
  it "overrides native objc methods" do
    m = mock('foo')
    m.expects(:init).returns(m)
    m.init
  end
end

$ macruby t.rb
Mocha on MacRuby
- overrides native objc methods

1 specifications (1 requirements), 0 failures, 0 errors

Sorry I haven't had a chance to this about this much more. I've just added it as a Lighthouse ticket with some initial thoughts. Cheers, James.