ruby/test/test_delegate.rb

require 'test/unit'
require 'delegate'

class TestDelegateClass < Test::Unit::TestCase
  module M
    attr_reader :m
  end

  def test_extend
    obj = DelegateClass(Array).new([])
    obj.instance_eval { @m = :m }
    obj.extend M
    assert_equal(:m, obj.m, "[ruby-dev:33116]")
  end

  # became pending by [ruby-dev:36950].
  # def test_systemcallerror_eq
  #   e = SystemCallError.new(0)
  #   assert((SimpleDelegator.new(e) == e) == (e == SimpleDelegator.new(e)), "[ruby-dev:34808]")
  # end

  class Myclass < DelegateClass(Array);end

  def test_delegateclass_class
    myclass=Myclass.new([])
    assert_equal(Myclass,myclass.class)
  end

  def test_simpledelegator_class
    simple=SimpleDelegator.new([])
    assert_equal(SimpleDelegator,simple.class)
  end

  class Foo
    def m
      :m
    end
  end

  class Bar < DelegateClass(Foo)
  end

  def test_override
    ::Object.class_eval{ def m; :o end }
    assert_equal(:o, Object.new.m)
    assert_equal(:m, Foo.new.m)
    assert_equal(:m, SimpleDelegator.new(Foo.new).m)
    assert_equal(:m, Bar.new(Foo.new).m)
  ensure
    ::Object.class_eval{ remove_method :m }
  end
end