ruby--ruby/test/ruby/test_module.rb

require 'test/unit'
require 'pp'
require_relative 'envutil'

$m0 = Module.nesting

class TestModule < Test::Unit::TestCase
  def _wrap_assertion
    yield
  end

  def assert_method_defined?(klass, mid, message="")
    message = build_message(message, "#{klass}\##{mid} expected to be defined.")
    _wrap_assertion do
      klass.method_defined?(mid) or
        raise Test::Unit::AssertionFailedError, message, caller(3)
    end
  end

  def assert_method_not_defined?(klass, mid, message="")
    message = build_message(message, "#{klass}\##{mid} expected to not be defined.")
    _wrap_assertion do
      klass.method_defined?(mid) and
        raise Test::Unit::AssertionFailedError, message, caller(3)
    end
  end

  def setup
    @verbose = $VERBOSE
    $VERBOSE = nil
  end

  def teardown
    $VERBOSE = @verbose
  end

  def test_LT_0
    assert_equal true, String < Object
    assert_equal false, Object < String
    assert_nil String < Array
    assert_equal true, Array < Enumerable
    assert_equal false, Enumerable < Array
    assert_nil Proc < Comparable
    assert_nil Comparable < Proc
  end

  def test_GT_0
    assert_equal false, String > Object
    assert_equal true, Object > String
    assert_nil String > Array
    assert_equal false, Array > Enumerable
    assert_equal true, Enumerable > Array
    assert_nil Comparable > Proc
    assert_nil Proc > Comparable
  end

  def test_CMP_0
    assert_equal(-1, (String <=> Object))
    assert_equal 1, (Object <=> String)
    assert_nil(Array <=> String)
  end

  ExpectedException = NoMethodError

  # Support stuff

  module Mixin
    MIXIN = 1
    def mixin
    end
  end

  module User
    USER = 2
    include Mixin
    def user
    end
  end

  module Other
    def other
    end
  end

  class AClass
    def AClass.cm1
      "cm1"
    end
    def AClass.cm2
      cm1 + "cm2" + cm3
    end
    def AClass.cm3
      "cm3"
    end

    private_class_method :cm1, "cm3"

    def aClass
      :aClass
    end

    def aClass1
      :aClass1
    end

    def aClass2
      :aClass2
    end

    private :aClass1
    protected :aClass2
  end

  class BClass < AClass
    def bClass1
      :bClass1
    end

    private

    def bClass2
      :bClass2
    end

    protected
    def bClass3
      :bClass3
    end
  end

  class CClass < BClass
    def self.cClass
    end
  end

  MyClass = AClass.clone
  class MyClass
    public_class_method :cm1
  end

  # -----------------------------------------------------------

  def test_CMP # '<=>'
    assert_equal( 0, Mixin <=> Mixin)
    assert_equal(-1, User <=> Mixin)
    assert_equal( 1, Mixin <=> User)

    assert_equal( 0, Object <=> Object)
    assert_equal(-1, String <=> Object)
    assert_equal( 1, Object <=> String)
  end

  def test_GE # '>='
    assert(Mixin >= User)
    assert(Mixin >= Mixin)
    assert(!(User >= Mixin))

    assert(Object >= String)
    assert(String >= String)
    assert(!(String >= Object))
  end

  def test_GT # '>'
    assert(Mixin   > User)
    assert(!(Mixin > Mixin))
    assert(!(User  > Mixin))

    assert(Object > String)
    assert(!(String > String))
    assert(!(String > Object))
  end

  def test_LE # '<='
    assert(User <= Mixin)
    assert(Mixin <= Mixin)
    assert(!(Mixin <= User))

    assert(String <= Object)
    assert(String <= String)
    assert(!(Object <= String))
  end

  def test_LT # '<'
    assert(User < Mixin)
    assert(!(Mixin < Mixin))
    assert(!(Mixin < User))

    assert(String < Object)
    assert(!(String < String))
    assert(!(Object < String))
  end

  def test_VERY_EQUAL # '==='
    assert(Object === self)
    assert(Test::Unit::TestCase === self)
    assert(TestModule === self)
    assert(!(String === self))
  end

  def test_ancestors
    assert_equal([User, Mixin],      User.ancestors)
    assert_equal([Mixin],            Mixin.ancestors)

    ancestors = Object.ancestors
    mixins = ancestors - [Object, Kernel, BasicObject]
    mixins << JSON::Ext::Generator::GeneratorMethods::String if defined?(JSON::Ext::Generator::GeneratorMethods::String)
    assert_equal([Object, Kernel, BasicObject], ancestors - mixins)
    assert_equal([String, Comparable, Object, Kernel, BasicObject], String.ancestors - mixins)
  end

  CLASS_EVAL = 2
  @@class_eval = 'b'

  def test_class_eval
    Other.class_eval("CLASS_EVAL = 1")
    assert_equal(1, Other::CLASS_EVAL)
    assert(Other.constants.include?(:CLASS_EVAL))
    assert_equal(2, Other.class_eval { CLASS_EVAL })

    Other.class_eval("@@class_eval = 'a'")
    assert_equal('a', Other.class_variable_get(:@@class_eval))
    assert_equal('b', Other.class_eval { @@class_eval })

    Other.class_eval do
      module_function

      def class_eval_test
        "foo"
      end
    end
    assert_equal("foo", Other.class_eval_test)

    assert_equal([Other], Other.class_eval { |*args| args })
  end

  def test_const_defined?
    assert(Math.const_defined?(:PI))
    assert(Math.const_defined?("PI"))
    assert(!Math.const_defined?(:IP))
    assert(!Math.const_defined?("IP"))
  end

  def test_const_get
    assert_equal(Math::PI, Math.const_get("PI"))
    assert_equal(Math::PI, Math.const_get(:PI))
  end

  def test_const_set
    assert(!Other.const_defined?(:KOALA))
    Other.const_set(:KOALA, 99)
    assert(Other.const_defined?(:KOALA))
    assert_equal(99, Other::KOALA)
    Other.const_set("WOMBAT", "Hi")
    assert_equal("Hi", Other::WOMBAT)
  end

  def test_constants
    assert_equal([:MIXIN], Mixin.constants)
    assert_equal([:MIXIN, :USER], User.constants.sort)
  end

  def test_dup
    bug6454 = '[ruby-core:45132]'

    a = Module.new
    Other.const_set :BUG6454, a

    original = Other::BUG6454.inspect

    b = a.dup
    Other.const_set :BUG6454_dup, b

    assert_equal "TestModule::Other::BUG6454_dup", b.inspect, bug6454
  end

  def test_dup_anonymous
    bug6454 = '[ruby-core:45132]'

    a = Module.new
    original = a.inspect

    b = a.dup

    refute_equal original, b.inspect, bug6454
  end

  def test_included_modules
    assert_equal([], Mixin.included_modules)
    assert_equal([Mixin], User.included_modules)

    mixins = Object.included_modules - [Kernel]
    mixins << JSON::Ext::Generator::GeneratorMethods::String if defined?(JSON::Ext::Generator::GeneratorMethods::String)
    assert_equal([Kernel], Object.included_modules - mixins)
    assert_equal([Comparable, Kernel], String.included_modules - mixins)
  end

  def test_instance_methods
    assert_equal([:user], User.instance_methods(false))
    assert_equal([:user, :mixin].sort, User.instance_methods(true).sort)
    assert_equal([:mixin], Mixin.instance_methods)
    assert_equal([:mixin], Mixin.instance_methods(true))
    assert_equal([:cClass], (class << CClass; self; end).instance_methods(false))
    assert_equal([], (class << BClass; self; end).instance_methods(false))
    assert_equal([:cm2], (class << AClass; self; end).instance_methods(false))
    # Ruby 1.8 feature change:
    # #instance_methods includes protected methods.
    #assert_equal([:aClass], AClass.instance_methods(false))
    assert_equal([:aClass, :aClass2], AClass.instance_methods(false).sort)
    assert_equal([:aClass, :aClass2],
        (AClass.instance_methods(true) - Object.instance_methods(true)).sort)
  end

  def test_method_defined?
    assert_method_not_defined?(User, :wombat)
    assert_method_defined?(User, :user)
    assert_method_defined?(User, :mixin)
    assert_method_not_defined?(User, :wombat)
    assert_method_defined?(User, :user)
    assert_method_defined?(User, :mixin)
  end

  def module_exec_aux
    Proc.new do
      def dynamically_added_method_3; end
    end
  end
  def module_exec_aux_2(&block)
    User.module_exec(&block)
  end

  def test_module_exec
    User.module_exec do
      def dynamically_added_method_1; end
    end
    assert_method_defined?(User, :dynamically_added_method_1)

    block = Proc.new do
      def dynamically_added_method_2; end
    end
    User.module_exec(&block)
    assert_method_defined?(User, :dynamically_added_method_2)

    User.module_exec(&module_exec_aux)
    assert_method_defined?(User, :dynamically_added_method_3)

    module_exec_aux_2 do
      def dynamically_added_method_4; end
    end
    assert_method_defined?(User, :dynamically_added_method_4)
  end

  def test_module_eval
    User.module_eval("MODULE_EVAL = 1")
    assert_equal(1, User::MODULE_EVAL)
    assert(User.constants.include?(:MODULE_EVAL))
    User.instance_eval("remove_const(:MODULE_EVAL)")
    assert(!User.constants.include?(:MODULE_EVAL))
  end

  def test_name
    assert_equal("Fixnum", Fixnum.name)
    assert_equal("TestModule::Mixin",  Mixin.name)
    assert_equal("TestModule::User",   User.name)
  end

  def test_classpath
    m = Module.new
    n = Module.new
    m.const_set(:N, n)
    assert_nil(m.name)
    assert_nil(n.name)
    assert_equal([:N], m.constants)
    m.module_eval("module O end")
    assert_equal([:N, :O], m.constants)
    assert_nil(m::N.name)
    assert_match(/\A(?:#<Module:.*>::)?O\z/, m::O.name)
    self.class.const_set(:M, m)
    prefix = self.class.name + "::M::"
    assert_equal(prefix+"N", m.const_get(:N).name)
    assert_equal(prefix+"O", m.const_get(:O).name)
  end

  def test_private_class_method
    assert_raise(ExpectedException) { AClass.cm1 }
    assert_raise(ExpectedException) { AClass.cm3 }
    assert_equal("cm1cm2cm3", AClass.cm2)
  end

  def test_private_instance_methods
    assert_equal([:aClass1], AClass.private_instance_methods(false))
    assert_equal([:bClass2], BClass.private_instance_methods(false))
    assert_equal([:aClass1, :bClass2],
        (BClass.private_instance_methods(true) -
         Object.private_instance_methods(true)).sort)
  end

  def test_protected_instance_methods
    assert_equal([:aClass2], AClass.protected_instance_methods)
    assert_equal([:bClass3], BClass.protected_instance_methods(false))
    assert_equal([:bClass3, :aClass2].sort,
                 (BClass.protected_instance_methods(true) -
                  Object.protected_instance_methods(true)).sort)
  end

  def test_public_class_method
    assert_equal("cm1",       MyClass.cm1)
    assert_equal("cm1cm2cm3", MyClass.cm2)
    assert_raise(ExpectedException) { eval "MyClass.cm3" }
  end

  def test_public_instance_methods
    assert_equal([:aClass],  AClass.public_instance_methods(false))
    assert_equal([:bClass1], BClass.public_instance_methods(false))
  end

  def test_s_constants
    c1 = Module.constants
    Object.module_eval "WALTER = 99"
    c2 = Module.constants
    assert_equal([:WALTER], c2 - c1)

    assert_equal([], Module.constants(true))
    assert_equal([], Module.constants(false))

    src = <<-INPUT
      ary = Module.constants
      module M
        WALTER = 99
      end
      class Module
        include M
      end
      p Module.constants - ary, Module.constants(true), Module.constants(false)
    INPUT
    assert_in_out_err([], src, %w([:M] [:WALTER] []), [])

    klass = Class.new do
      const_set(:X, 123)
    end
    assert_equal(false, klass.class_eval { Module.constants }.include?(:X))
  end

  module M1
    $m1 = Module.nesting
    module M2
      $m2 = Module.nesting
    end
  end

  def test_s_nesting
    assert_equal([],                               $m0)
    assert_equal([TestModule::M1, TestModule],     $m1)
    assert_equal([TestModule::M1::M2,
                  TestModule::M1, TestModule],     $m2)
  end

  def test_s_new
    m = Module.new
    assert_instance_of(Module, m)
  end

  def test_freeze
    m = Module.new
    m.freeze
    assert_raise(RuntimeError) do
      m.module_eval do
        def foo; end
      end
    end
  end

  def test_attr_obsoleted_flag
    c = Class.new
    c.class_eval do
      def initialize
        @foo = :foo
        @bar = :bar
      end
      attr :foo, true
      attr :bar, false
    end
    o = c.new
    assert_equal(true, o.respond_to?(:foo))
    assert_equal(true, o.respond_to?(:foo=))
    assert_equal(true, o.respond_to?(:bar))
    assert_equal(false, o.respond_to?(:bar=))
  end

  def test_const_get_evaled
    c1 = Class.new
    c2 = Class.new(c1)

    eval("c1::Foo = :foo")
    assert_equal(:foo, c1::Foo)
    assert_equal(:foo, c2::Foo)
    assert_equal(:foo, c2.const_get(:Foo))
    assert_raise(NameError) { c2.const_get(:Foo, false) }

    eval("c1::Foo = :foo")
    assert_raise(NameError) { c1::Bar }
    assert_raise(NameError) { c2::Bar }
    assert_raise(NameError) { c2.const_get(:Bar) }
    assert_raise(NameError) { c2.const_get(:Bar, false) }
    assert_raise(NameError) { c2.const_get("Bar", false) }
    assert_raise(NameError) { c2.const_get("BaR11", false) }
    assert_raise(NameError) { Object.const_get("BaR11", false) }

    c1.instance_eval do
      def const_missing(x)
        x
      end
    end

    assert_equal(:Bar, c1::Bar)
    assert_equal(:Bar, c2::Bar)
    assert_equal(:Bar, c2.const_get(:Bar))
    assert_equal(:Bar, c2.const_get(:Bar, false))
    assert_equal(:Bar, c2.const_get("Bar"))
    assert_equal(:Bar, c2.const_get("Bar", false))

    v = c2.const_get("Bar11", false)
    assert_equal("Bar11".to_sym, v)

    assert_raise(NameError) { c1.const_get(:foo) }
  end

  def test_const_set_invalid_name
    c1 = Class.new
    assert_raise(NameError) { c1.const_set(:foo, :foo) }
  end

  def test_const_get_invalid_name
    c1 = Class.new
    assert_raise(NameError) { c1.const_defined?(:foo) }
    bug5084 = '[ruby-dev:44200]'
    assert_raise(TypeError, bug5084) { c1.const_defined?(1) }
  end

  def test_const_get_no_inherited
    bug3422 = '[ruby-core:30719]'
    assert_in_out_err([], <<-INPUT, %w[1 NameError A], [], bug3422)
    BasicObject::A = 1
    puts [true, false].map {|inh|
      begin
        Object.const_get(:A, inh)
      rescue NameError => e
        [e.class, e.name]
      end
    }
    INPUT
  end

  def test_const_get_inherited
    bug3423 = '[ruby-core:30720]'
    assert_in_out_err([], <<-INPUT, %w[NameError A NameError A], [], bug3423)
    module Foo; A = 1; end
    class Object; include Foo; end
    class Bar; include Foo; end

    puts [Object, Bar].map {|klass|
      begin
        klass.const_get(:A, false)
      rescue NameError => e
        [e.class, e.name]
      end
    }
    INPUT
  end

  def test_const_in_module
    bug3423 = '[ruby-core:37698]'
    assert_in_out_err([], <<-INPUT, %w[ok], [], bug3423)
    module LangModuleSpecInObject
      module LangModuleTop
      end
    end
    include LangModuleSpecInObject
    module LangModuleTop
    end
    puts "ok" if LangModuleSpecInObject::LangModuleTop == LangModuleTop
    INPUT

    bug5264 = '[ruby-core:39227]'
    assert_in_out_err([], <<-'INPUT', [], [], bug5264)
    class A
      class X; end
    end
    class B < A
      module X; end
    end
    INPUT
  end

  def test_class_variable_get
    c = Class.new
    c.class_eval('@@foo = :foo')
    assert_equal(:foo, c.class_variable_get(:@@foo))
    assert_raise(NameError) { c.class_variable_get(:@@bar) } # c.f. instance_variable_get
    assert_raise(NameError) { c.class_variable_get(:foo) }
  end

  def test_class_variable_set
    c = Class.new
    c.class_variable_set(:@@foo, :foo)
    assert_equal(:foo, c.class_eval('@@foo'))
    assert_raise(NameError) { c.class_variable_set(:foo, 1) }
  end

  def test_class_variable_defined
    c = Class.new
    c.class_eval('@@foo = :foo')
    assert_equal(true, c.class_variable_defined?(:@@foo))
    assert_equal(false, c.class_variable_defined?(:@@bar))
    assert_raise(NameError) { c.class_variable_defined?(:foo) }
  end

  def test_remove_class_variable
    c = Class.new
    c.class_eval('@@foo = :foo')
    c.class_eval { remove_class_variable(:@@foo) }
    assert_equal(false, c.class_variable_defined?(:@@foo))
  end

  def test_export_method
    m = Module.new
    assert_raise(NameError) do
      m.instance_eval { public(:foo) }
    end
  end

  def test_attr
    assert_in_out_err([], <<-INPUT, %w(:ok nil), /warning: private attribute\?$/)
      $VERBOSE = true
      c = Class.new
      c.instance_eval do
        private
        attr_reader :foo
      end
      o = c.new
      o.foo rescue p(:ok)
      p(o.instance_eval { foo })
    INPUT

    c = Class.new
    assert_raise(NameError) do
      c.instance_eval { attr_reader :"." }
    end
  end

  def test_undef
    assert_raise(SecurityError) do
      Thread.new do
        $SAFE = 4
        Class.instance_eval { undef_method(:foo) }
      end.join
    end

    c = Class.new
    assert_raise(NameError) do
      c.instance_eval { undef_method(:foo) }
    end

    m = Module.new
    assert_raise(NameError) do
      m.instance_eval { undef_method(:foo) }
    end

    o = Object.new
    assert_raise(NameError) do
      class << o; self; end.instance_eval { undef_method(:foo) }
    end

    %w(object_id __send__ initialize).each do |n|
      assert_in_out_err([], <<-INPUT, [], /warning: undefining `#{n}' may cause serious problems$/)
        $VERBOSE = false
        Class.new.instance_eval { undef_method(:#{n}) }
      INPUT
    end
  end

  def test_alias
    m = Module.new
    assert_raise(NameError) do
      m.class_eval { alias foo bar }
    end

    assert_in_out_err([], <<-INPUT, %w(2), /discarding old foo$/)
      $VERBOSE = true
      c = Class.new
      c.class_eval do
        def foo; 1; end
        def bar; 2; end
      end
      c.class_eval { alias foo bar }
      p c.new.foo
    INPUT
  end

  def test_mod_constants
    m = Module.new
    m.const_set(:Foo, :foo)
    assert_equal([:Foo], m.constants(true))
    assert_equal([:Foo], m.constants(false))
    m.instance_eval { remove_const(:Foo) }
  end

  def test_frozen_class
    m = Module.new
    m.freeze
    assert_raise(RuntimeError) do
      m.instance_eval { undef_method(:foo) }
    end

    c = Class.new
    c.freeze
    assert_raise(RuntimeError) do
      c.instance_eval { undef_method(:foo) }
    end

    o = Object.new
    c = class << o; self; end
    c.freeze
    assert_raise(RuntimeError) do
      c.instance_eval { undef_method(:foo) }
    end
  end

  def test_method_defined
    c = Class.new
    c.class_eval do
      def foo; end
      def bar; end
      def baz; end
      public :foo
      protected :bar
      private :baz
    end

    assert_equal(true, c.public_method_defined?(:foo))
    assert_equal(false, c.public_method_defined?(:bar))
    assert_equal(false, c.public_method_defined?(:baz))

    assert_equal(false, c.protected_method_defined?(:foo))
    assert_equal(true, c.protected_method_defined?(:bar))
    assert_equal(false, c.protected_method_defined?(:baz))

    assert_equal(false, c.private_method_defined?(:foo))
    assert_equal(false, c.private_method_defined?(:bar))
    assert_equal(true, c.private_method_defined?(:baz))
  end

  def test_change_visibility_under_safe4
    c = Class.new
    c.class_eval do
      def foo; end
    end
    assert_raise(SecurityError) do
      Thread.new do
        $SAFE = 4
        c.class_eval { private :foo }
      end.join
    end
  end

  def test_top_public_private
    assert_in_out_err([], <<-INPUT, %w([:foo] [:bar]), [])
      private
      def foo; :foo; end
      public
      def bar; :bar; end
      p self.private_methods.grep(/^foo$|^bar$/)
      p self.methods.grep(/^foo$|^bar$/)
    INPUT
  end

  def test_append_features
    t = nil
    m = Module.new
    m.module_eval do
      def foo; :foo; end
    end
    class << m; self; end.class_eval do
      define_method(:append_features) do |mod|
        t = mod
        super(mod)
      end
    end

    m2 = Module.new
    m2.module_eval { include(m) }
    assert_equal(m2, t)

    o = Object.new
    o.extend(m2)
    assert_equal(true, o.respond_to?(:foo))
  end

  def test_append_features_raise
    m = Module.new
    m.module_eval do
      def foo; :foo; end
    end
    class << m; self; end.class_eval do
      define_method(:append_features) {|mod| raise }
    end

    m2 = Module.new
    assert_raise(RuntimeError) do
      m2.module_eval { include(m) }
    end

    o = Object.new
    o.extend(m2)
    assert_equal(false, o.respond_to?(:foo))
  end

  def test_append_features_type_error
    assert_raise(TypeError) do
      Module.new.instance_eval { append_features(1) }
    end
  end

  def test_included
    m = Module.new
    m.module_eval do
      def foo; :foo; end
    end
    class << m; self; end.class_eval do
      define_method(:included) {|mod| raise }
    end

    m2 = Module.new
    assert_raise(RuntimeError) do
      m2.module_eval { include(m) }
    end

    o = Object.new
    o.extend(m2)
    assert_equal(true, o.respond_to?(:foo))
  end

  def test_cyclic_include
    m1 = Module.new
    m2 = Module.new
    m1.instance_eval { include(m2) }
    assert_raise(ArgumentError) do
      m2.instance_eval { include(m1) }
    end
  end

  def test_include_p
    m = Module.new
    c1 = Class.new
    c1.instance_eval { include(m) }
    c2 = Class.new(c1)
    assert_equal(true, c1.include?(m))
    assert_equal(true, c2.include?(m))
    assert_equal(false, m.include?(m))
  end

  def test_include_under_safe4
    m = Module.new
    c1 = Class.new
    assert_raise(SecurityError) do
      lambda {
        $SAFE = 4
        c1.instance_eval { include(m) }
      }.call
    end
    assert_nothing_raised do
      lambda {
        $SAFE = 4
        c2 = Class.new
        c2.instance_eval { include(m) }
      }.call
    end
  end

  def test_send
    a = AClass.new
    assert_equal(:aClass, a.__send__(:aClass))
    assert_equal(:aClass1, a.__send__(:aClass1))
    assert_equal(:aClass2, a.__send__(:aClass2))
    b = BClass.new
    assert_equal(:aClass, b.__send__(:aClass))
    assert_equal(:aClass1, b.__send__(:aClass1))
    assert_equal(:aClass2, b.__send__(:aClass2))
    assert_equal(:bClass1, b.__send__(:bClass1))
    assert_equal(:bClass2, b.__send__(:bClass2))
    assert_equal(:bClass3, b.__send__(:bClass3))
  end


  def test_nonascii_name
    c = eval("class ::C\u{df}; self; end")
    assert_equal("C\u{df}", c.name, '[ruby-core:24600]')
    c = eval("class C\u{df}; self; end")
    assert_equal("TestModule::C\u{df}", c.name, '[ruby-core:24600]')
  end

  def test_method_added
    memo = []
    mod = Module.new do
      mod = self
      (class << self ; self ; end).class_eval do
        define_method :method_added do |sym|
          memo << sym
          memo << mod.instance_methods(false)
          memo << (mod.instance_method(sym) rescue nil)
        end
      end
      def f
      end
      alias g f
      attr_reader :a
      attr_writer :a
    end
    assert_equal :f, memo.shift
    assert_equal [:f], memo.shift, '[ruby-core:25536]'
    assert_equal mod.instance_method(:f), memo.shift
    assert_equal :g, memo.shift
    assert_equal [:f, :g], memo.shift
    assert_equal mod.instance_method(:f), memo.shift
    assert_equal :a, memo.shift
    assert_equal [:f, :g, :a], memo.shift
    assert_equal mod.instance_method(:a), memo.shift
    assert_equal :a=, memo.shift
    assert_equal [:f, :g, :a, :a=], memo.shift
    assert_equal mod.instance_method(:a=), memo.shift
  end

  def test_method_undefined
    added = []
    undefed = []
    removed = []
    mod = Module.new do
      mod = self
      def f
      end
      (class << self ; self ; end).class_eval do
        define_method :method_added do |sym|
          added << sym
        end
        define_method :method_undefined do |sym|
          undefed << sym
        end
        define_method :method_removed do |sym|
          removed << sym
        end
      end
    end
    assert_method_defined?(mod, :f)
    mod.module_eval do
      undef :f
    end
    assert_equal [], added
    assert_equal [:f], undefed
    assert_equal [], removed
  end

  def test_method_removed
    added = []
    undefed = []
    removed = []
    mod = Module.new do
      mod = self
      def f
      end
      (class << self ; self ; end).class_eval do
        define_method :method_added do |sym|
          added << sym
        end
        define_method :method_undefined do |sym|
          undefed << sym
        end
        define_method :method_removed do |sym|
          removed << sym
        end
      end
    end
    assert_method_defined?(mod, :f)
    mod.module_eval do
      remove_method :f
    end
    assert_equal [], added
    assert_equal [], undefed
    assert_equal [:f], removed
  end

  def test_method_redefinition
    feature2155 = '[ruby-dev:39400]'

    line = __LINE__+4
    stderr = EnvUtil.verbose_warning do
      Module.new do
        def foo; end
        def foo; end
      end
    end
    assert_match(/:#{line}: warning: method redefined; discarding old foo/, stderr)
    assert_match(/:#{line-1}: warning: previous definition of foo/, stderr, feature2155)

    stderr = EnvUtil.verbose_warning do
      Module.new do
        def foo; end
        alias bar foo
        def foo; end
      end
    end
    assert_equal("", stderr)

    stderr = EnvUtil.verbose_warning do
      Module.new do
        def foo; end
        alias bar foo
        alias bar foo
      end
    end
    assert_equal("", stderr)

    line = __LINE__+4
    stderr = EnvUtil.verbose_warning do
      Module.new do
        define_method(:foo) do end
        def foo; end
      end
    end
    assert_match(/:#{line}: warning: method redefined; discarding old foo/, stderr)
    assert_match(/:#{line-1}: warning: previous definition of foo/, stderr, feature2155)

    stderr = EnvUtil.verbose_warning do
      Module.new do
        define_method(:foo) do end
        alias bar foo
        alias bar foo
      end
    end
    assert_equal("", stderr)

    stderr = EnvUtil.verbose_warning do
      Module.new do
        module_function
        def foo; end
        module_function :foo
      end
    end
    assert_equal("", stderr, '[ruby-dev:39397]')

    stderr = EnvUtil.verbose_warning do
      Module.new do
        def foo; end
        undef foo
      end
    end
    assert_equal("", stderr)
  end

  def test_protected_singleton_method
    klass = Class.new
    x = klass.new
    class << x
      protected

      def foo
      end
    end
    assert_raise(NoMethodError) do
      x.foo
    end
    klass.send(:define_method, :bar) do
      x.foo
    end
    assert_nothing_raised do
      x.bar
    end
    y = klass.new
    assert_raise(NoMethodError) do
      y.bar
    end
  end

  def test_uninitialized_toplevel_constant
    bug3123 = '[ruby-dev:40951]'
    e = assert_raise(NameError) {eval("Bug3123", TOPLEVEL_BINDING)}
    assert_not_match(/Object::/, e.message, bug3123)
  end

  def test_attr_inherited_visibility
    bug3406 = '[ruby-core:30638]'
    c = Class.new do
      class << self
        private
        def attr_accessor(*); super; end
      end
      attr_accessor :x
    end.new
    assert_nothing_raised(bug3406) {c.x = 1}
    assert_equal(1, c.x, bug3406)
  end

  def test_private_constant
    c = Class.new
    c.const_set(:FOO, "foo")
    assert_equal("foo", c::FOO)
    c.private_constant(:FOO)
    assert_raise(NameError) { c::FOO }
    assert_equal("foo", c.class_eval("FOO"))
    assert_equal("foo", c.const_get("FOO"))
    $VERBOSE, verbose = nil, $VERBOSE
    c.const_set(:FOO, "foo")
    $VERBOSE = verbose
    assert_raise(NameError) { c::FOO }
  end

  def test_private_constant2
    c = Class.new
    c.const_set(:FOO, "foo")
    c.const_set(:BAR, "bar")
    assert_equal("foo", c::FOO)
    assert_equal("bar", c::BAR)
    c.private_constant(:FOO, :BAR)
    assert_raise(NameError) { c::FOO }
    assert_raise(NameError) { c::BAR }
    assert_equal("foo", c.class_eval("FOO"))
    assert_equal("bar", c.class_eval("BAR"))
  end

  class PrivateClass
  end
  private_constant :PrivateClass

  def test_define_module_under_private_constant
    assert_raise(NameError) do
      eval %q{class TestModule::PrivateClass; end}
    end
    assert_raise(NameError) do
      eval %q{module TestModule::PrivateClass::TestModule; end}
    end
    eval %q{class PrivateClass; end}
    eval %q{module PrivateClass::TestModule; end}
    assert_instance_of(Module, PrivateClass::TestModule)
    PrivateClass.class_eval { remove_const(:TestModule) }
  end

  def test_public_constant
    c = Class.new
    c.const_set(:FOO, "foo")
    assert_equal("foo", c::FOO)
    c.private_constant(:FOO)
    assert_raise(NameError) { c::FOO }
    assert_equal("foo", c.class_eval("FOO"))
    c.public_constant(:FOO)
    assert_equal("foo", c::FOO)
  end

  def test_constants_with_private_constant
    assert(!(::TestModule).constants.include?(:PrivateClass))
  end

  def test_toplevel_private_constant
    src = <<-INPUT
      class Object
        private_constant :Object
      end
      p Object
      begin
        p ::Object
      rescue
        p :ok
      end
    INPUT
    assert_in_out_err([], src, %w(Object :ok), [])
  end

  def test_private_constants_clear_inlinecache
    bug5702 = '[ruby-dev:44929]'
    src = <<-INPUT
    class A
      C = :Const
      def self.get_C
        A::C
      end
      # fill cache
      A.get_C
      private_constant :C, :D rescue nil
      begin
        A.get_C
      rescue NameError
        puts "A.get_C"
      end
    end
    INPUT
    assert_in_out_err([], src, %w(A.get_C), [], bug5702)
  end

  def test_constant_lookup_in_method_defined_by_class_eval
    src = <<-INPUT
      class A
        B = 42
      end

      A.class_eval do
        def self.f
          B
        end

        def f
          B
        end
      end

      begin
        A.f
      rescue NameError
        puts "A.f"
      end
      begin
        A.new.f
      rescue NameError
        puts "A.new.f"
      end
    INPUT
    assert_in_out_err([], src, %w(A.f A.new.f), [])
  end

  def test_constant_lookup_in_toplevel_class_eval
    src = <<-INPUT
      module X
        A = 123
      end
      begin
        X.class_eval { A }
      rescue NameError => e
        puts e
      end
    INPUT
    assert_in_out_err([], src, ["uninitialized constant A"], [])
  end

  def test_constant_lookup_in_module_in_class_eval
    src = <<-INPUT
      class A
        B = 42
      end

      A.class_eval do
        module C
          begin
            B
          rescue NameError
            puts "NameError"
          end
        end
      end
    INPUT
    assert_in_out_err([], src, ["NameError"], [])
  end

  module M0
    def m1; [:M0] end
  end
  module M1
    def m1; [:M1, *super] end
  end
  module M2
    def m1; [:M2, *super] end
  end
  M3 = Module.new do
    def m1; [:M3, *super] end
  end
  module M4
    def m1; [:M4, *super] end
  end
  class C
    def m1; end
  end
  class C0 < C
    include M0
    prepend M1
    def m1; [:C0, *super] end
  end
  class C1 < C0
    prepend M2, M3
    include M4
    def m1; [:C1, *super] end
  end

  def test_prepend
    obj = C0.new
    expected = [:M1,:C0,:M0]
    assert_equal(expected, obj.m1)
    obj = C1.new
    expected = [:M2,:M3,:C1,:M4,:M1,:C0,:M0]
    assert_equal(expected, obj.m1)
  end

  def test_prepend_inheritance
    bug6654 = '[ruby-core:45914]'
    a = labeled_module("a")
    b = labeled_module("b") {include a}
    c = labeled_class("c") {prepend b}
    assert_operator(c, :<, b, bug6654)
    assert_operator(c, :<, a, bug6654)
  end

  def test_prepend_instance_methods
    bug6655 = '[ruby-core:45915]'
    assert_equal(Object.instance_methods, Class.new {prepend Module.new}.instance_methods, bug6655)
  end

  def test_prepend_singleton_methods
    o = Object.new
    o.singleton_class.class_eval {prepend Module.new}
    assert_equal([], o.singleton_methods)
  end

  def test_prepend_remove_method
    assert_raise(NameError) do
      Class.new do
        prepend Module.new {def foo; end}
        remove_method(:foo)
      end
    end
  end

  def test_prepend_class_ancestors
    bug6658 = '[ruby-core:45919]'
    m = labeled_module("m")
    c = labeled_class("c") {prepend m}
    assert_equal([m, c], c.ancestors[0, 2], bug6658)

    bug6662 = '[ruby-dev:45868]'
    c2 = labeled_class("c2", c)
    anc = c2.ancestors
    assert_equal([c2, m, c, Object], anc[0..anc.index(Object)], bug6662)
  end

  def test_prepend_module_ancestors
    bug6659 = '[ruby-dev:45861]'
    m0 = labeled_module("m0") {def x; [:m0, *super] end}
    m1 = labeled_module("m1") {def x; [:m1, *super] end; prepend m0}
    m2 = labeled_module("m2") {def x; [:m2, *super] end; prepend m1}
    c0 = labeled_class("c0") {def x; [:c0] end}
    c1 = labeled_class("c1") {def x; [:c1] end; prepend m2}
    c2 = labeled_class("c2", c0) {def x; [:c2, *super] end; include m2}

    assert_equal([m0, m1], m1.ancestors, bug6659)

    bug6662 = '[ruby-dev:45868]'
    assert_equal([m0, m1, m2], m2.ancestors, bug6662)
    assert_equal([m0, m1, m2, c1], c1.ancestors[0, 4], bug6662)
    assert_equal([:m0, :m1, :m2, :c1], c1.new.x)
    assert_equal([c2, m0, m1, m2, c0], c2.ancestors[0, 5], bug6662)
    assert_equal([:c2, :m0, :m1, :m2, :c0], c2.new.x)
  end

  def labeled_module(name, &block)
    Module.new do
      singleton_class.class_eval {define_method(:to_s) {name}}
      class_eval(&block) if block
    end
  end

  def labeled_class(name, superclass = Object, &block)
    Class.new(superclass) do
      singleton_class.class_eval {define_method(:to_s) {name}}
      class_eval(&block) if block
    end
  end

  def test_prepend_instance_methods_false
    bug6660 = '[ruby-dev:45863]'
    assert_equal([:m1], Class.new{ prepend Module.new; def m1; end }.instance_methods(false), bug6660)
    assert_equal([:m1], Class.new(Class.new{def m2;end}){ prepend Module.new; def m1; end }.instance_methods(false), bug6660)
  end

  def test_class_variables
    m = Module.new
    m.class_variable_set(:@@foo, 1)
    m2 = Module.new
    m2.send(:include, m)
    m2.class_variable_set(:@@bar, 2)
    assert_equal([:@@foo], m.class_variables)
    assert_equal([:@@bar, :@@foo], m2.class_variables)
    assert_equal([:@@bar, :@@foo], m2.class_variables(true))
    assert_equal([:@@bar], m2.class_variables(false))
  end
end