I'm not sure this is the right fix. For example, the following case should get the top-level Foo, and I don't think it will in your patch:

Foo = 1
module Bar
end
Bar.const_get('::Foo')

Hmm... am I missing something here?

test.rb:

Foo = 1
module Bar
end
puts Bar.const_get('::Foo')

module A 
  class B 
  end 
end

put Object.const_get('::A::B')

Using MRI 2.2 and patched JRuby:

$ rbenv shell 2.2.0
$ ruby test.rb
1
A::B

$ bin/jruby test.rb
1
A::B

Object.const_get('::A::B') is equivalent to Object.const_get('A::B'). Your other case does appear to show it working right, so perhaps I reviewed it poorly. Will try it locally.

Ok, I have a case that better illustrates the problem:

Foo = 1
module Bar; Foo = 2; end
Bar.const_get('::Foo')

Basically a leading :: should cause it to start searching at Object, rather than from the target class.

Now this is a perfect example of sticking to test cases instead of thinking. I'll take a look at this again. :)

@lumeet There are very likely test cases in MRI's suite (rake test:mri, test/mri/socket/) or in RubySpec (rake test:ruby:fast, spec/ruby/core/socket/) if you want to try getting them to run. If so, you can also remove tags/excludes from spec/tags or test/mri/excludes.

BTW, you can get access to Object with runtime.getObject.

Fixed via 5868779.