ruby--ruby/test/ruby/test_class.rb

require 'test/unit'
require_relative 'envutil'

class TestClass < Test::Unit::TestCase
  # ------------------
  # Various test classes
  # ------------------

  class ClassOne
    attr :num_args
    @@subs = []
    def initialize(*args)
      @num_args = args.size
      @args = args
    end
    def [](n)
      @args[n]
    end
    def ClassOne.inherited(klass)
      @@subs.push klass
    end
    def subs
      @@subs
    end
  end

  class ClassTwo < ClassOne
  end

  class ClassThree < ClassOne
  end

  class ClassFour < ClassThree
  end

  # ------------------
  # Start of tests
  # ------------------

  def test_s_inherited
    assert_equal([ClassTwo, ClassThree, ClassFour], ClassOne.new.subs)
  end

  def test_s_new
    c = Class.new
    assert_same(Class, c.class)
    assert_same(Object, c.superclass)

    c = Class.new(Fixnum)
    assert_same(Class, c.class)
    assert_same(Fixnum, c.superclass)
  end

  def test_00_new_basic
    a = ClassOne.new
    assert_equal(ClassOne, a.class)
    assert_equal(0, a.num_args)

    a = ClassOne.new(1, 2, 3)
    assert_equal(3, a.num_args)
    assert_equal(1, a[0])
  end

  def test_01_new_inherited
    a = ClassTwo.new
    assert_equal(ClassTwo, a.class)
    assert_equal(0, a.num_args)

    a = ClassTwo.new(1, 2, 3)
    assert_equal(3, a.num_args)
    assert_equal(1, a[0])
  end

  def test_superclass
    assert_equal(ClassOne, ClassTwo.superclass)
    assert_equal(Object,   ClassTwo.superclass.superclass)
    assert_equal(BasicObject, ClassTwo.superclass.superclass.superclass)
  end

  def test_class_cmp
    assert_raise(TypeError) { Class.new <= 1 }
    assert_raise(TypeError) { Class.new >= 1 }
    assert_nil(Class.new <=> 1)
  end

  def test_class_initialize
    assert_raise(TypeError) do
      Class.new.instance_eval { initialize }
    end
  end

  def test_instanciate_singleton_class
    c = class << Object.new; self; end
    assert_raise(TypeError) { c.new }
  end

  def test_superclass_of_basicobject
    assert_equal(nil, BasicObject.superclass)
  end

  def test_module_function
    c = Class.new
    assert_raise(TypeError) do
      Module.instance_method(:module_function).bind(c).call(:foo)
    end
  end

  def test_check_inheritable
    assert_raise(TypeError) { Class.new(Object.new) }

    o = Object.new
    c = class << o; self; end
    assert_raise(TypeError) { Class.new(c) }

    assert_nothing_raised { Class.new(Class) } # is it OK?
    assert_raise(TypeError) { eval("class Foo < Class; end") }
  end

  def test_initialize_copy
    c = Class.new
    assert_raise(TypeError) { c.instance_eval { initialize_copy(1) } }

    o = Object.new
    c = class << o; self; end
    assert_raise(TypeError) { c.dup }
  end

  def test_singleton_class
    assert_raise(TypeError) { 1.extend(Module.new) }
    assert_raise(TypeError) { :foo.extend(Module.new) }

    assert_in_out_err([], <<-INPUT, %w(:foo :foo true true), [])
      module Foo; def foo; :foo; end; end
      false.extend(Foo)
      true.extend(Foo)
      p false.foo
      p true.foo
      p FalseClass.include?(Foo)
      p TrueClass.include?(Foo)
    INPUT
  end

  def test_uninitialized
    assert_raise(TypeError) { Class.allocate.new }
    assert_raise(TypeError) { Class.allocate.superclass }
  end
end