Ruby weirdness

repro.rb

# jruby 1.7.4 (1.9.3p392) 2013-05-16 2390d3b on OpenJDK 64-Bit Server VM 1.7.0_40-b20 +indy [linux-amd64]


class Foo
  define_method(:initialize) do
  end
end

p Foo.public_instance_methods.include?(:initialize)    # mri false, jruby true,  rbx19 false
p Foo.protected_instance_methods.include?(:initialize) # mri false, jruby false, rbx19 false
p Foo.private_instance_methods.include?(:initialize)   # mri true,  jruby false, rbx19 true

class Bar
  def initialize
  end
end

p Bar.public_instance_methods.include?(:initialize)    # mri false, jruby false, rbx19 false
p Bar.protected_instance_methods.include?(:initialize) # mri false, jruby false, rbx19 false
p Bar.private_instance_methods.include?(:initialize)   # mri true,  jruby true,  rbx19 true