Separate meta-programming features to `mruby-metaprog` gem.

We assume meta-programming is less used in embedded environments.
We have moved following methods:

 * Kernel module
   global_variables, local_variables, singleton_class,
   instance_variables, instance_variables_defined?, instance_variable_get,
   instance_variable_set, methods, private_methods, public_methods,
   protected_methods, singleton_methods, define_singleton_methods

 * Module class
   class_variables, class_variables_defined?, class_variable_get,
   class_variable_set, remove_class_variable, included_modules,
   instance_methods, remove_method, method_removed, constants

 * Module class methods
   constants, nesting

Note:
Following meta-programming methods are kept in the core:

 * Module class
   alias_method, undef_method, ancestors, const_defined?, const_get,
   const_set, remove_const, method_defined?, define_method

 * Toplevel object
   define_method

`mruby-metaprog` gem is linked by default (specified in default.gembox).
When it is removed, it will save 40KB (stripped:8KB) on x86-64
environment last time I measured.

4 files changed, 39 insertions, 337 deletions

diff --git a/test/t/class.rb b/test/t/class.rb
index a5118fa93..85450f200 100644
--- a/test/t/class.rb
+++ b/test/t/class.rb
@@ -36,7 +36,7 @@ end
 
 assert('Class#new', '15.2.3.3.3') do
   assert_raise(TypeError, 'Singleton should raise TypeError') do
-    "a".singleton_class.new
+    (class <<"a"; self; end).new
   end
 
   class TestClass
@@ -293,15 +293,7 @@ assert('singleton tests') do
     end
   end
 
-  assert_false baz.singleton_methods.include? :run_foo_mod
-  assert_false baz.singleton_methods.include? :run_baz
-
-  assert_raise(NoMethodError, 'should raise NoMethodError') do
-    baz.run_foo_mod
-  end
-  assert_raise(NoMethodError, 'should raise NoMethodError') do
-    baz.run_baz
-  end
+  assert_equal :run_baz, baz
 
   assert_raise(NoMethodError, 'should raise NoMethodError') do
     bar.run_foo_mod
@@ -318,8 +310,8 @@ assert('singleton tests') do
     self
   end
 
-  assert_true baz.singleton_methods.include? :run_baz
-  assert_true baz.singleton_methods.include? :run_foo_mod
+  assert_true baz.respond_to? :run_baz
+  assert_true baz.respond_to? :run_foo_mod
   assert_equal 100, baz.run_foo_mod
   assert_equal 300, baz.run_baz
 
@@ -440,12 +432,3 @@ assert('class with non-class/module outer raises TypeError') do
   assert_raise(TypeError) { class 0::C1; end }
   assert_raise(TypeError) { class []::C2; end }
 end
-
-assert("remove_method doesn't segfault if the passed in argument isn't a symbol") do
-  klass = Class.new
-  assert_raise(TypeError) { klass.remove_method nil }
-  assert_raise(TypeError) { klass.remove_method 123 }
-  assert_raise(TypeError) { klass.remove_method 1.23 }
-  assert_raise(NameError) { klass.remove_method "hello" }
-  assert_raise(TypeError) { klass.remove_method Class.new }
-end
diff --git a/test/t/codegen.rb b/test/t/codegen.rb
index 4c9e2c594..154d44168 100644
--- a/test/t/codegen.rb
+++ b/test/t/codegen.rb
@@ -194,4 +194,4 @@ assert('register window of calls (#3783)') do
       alias send2 send
     end
   end
-end
\ No newline at end of file
+end
diff --git a/test/t/kernel.rb b/test/t/kernel.rb
index 561118302..9744bddba 100644
--- a/test/t/kernel.rb
+++ b/test/t/kernel.rb
@@ -103,7 +103,7 @@ assert('Kernel#__send__', '15.3.1.3.4') do
   # test with argument
   assert_true __send__(:respond_to?, :nil?)
   # test without argument and without block
-  assert_equal  Array, __send__(:public_methods).class
+  assert_equal String, __send__(:to_s).class
 end
 
 assert('Kernel#block_given?', '15.3.1.3.6') do
@@ -278,30 +278,6 @@ assert('Kernel#inspect', '15.3.1.3.17') do
   assert_equal "main", s
 end
 
-assert('Kernel#instance_variable_defined?', '15.3.1.3.20') do
-  o = Object.new
-  o.instance_variable_set(:@a, 1)
-
-  assert_true o.instance_variable_defined?("@a")
-  assert_false o.instance_variable_defined?("@b")
-  assert_true o.instance_variable_defined?("@a"[0,2])
-  assert_true o.instance_variable_defined?("@abc"[0,2])
-end
-
-assert('Kernel#instance_variables', '15.3.1.3.23') do
-  o = Object.new
-  o.instance_eval do
-    @a = 11
-    @b = 12
-  end
-  ivars = o.instance_variables
-
-  assert_equal Array, ivars.class,
-  assert_equal(2, ivars.size)
-  assert_true ivars.include?(:@a)
-  assert_true ivars.include?(:@b)
-end
-
 assert('Kernel#is_a?', '15.3.1.3.24') do
   assert_true is_a?(Kernel)
   assert_false is_a?(Array)
@@ -381,10 +357,6 @@ assert('Kernel#method_missing', '15.3.1.3.30') do
   end
 end
 
-assert('Kernel#methods', '15.3.1.3.31') do
-  assert_equal Array, methods.class
-end
-
 assert('Kernel#nil?', '15.3.1.3.32') do
   assert_false nil?
 end
@@ -408,23 +380,6 @@ end
 
 # Kernel#print is defined in mruby-print mrbgem. '15.3.1.3.35'
 
-assert('Kernel#private_methods', '15.3.1.3.36') do
-  assert_equal Array, private_methods.class
-end
-
-assert('Kernel#protected_methods', '15.3.1.3.37') do
-  assert_equal Array, protected_methods.class
-end
-
-assert('Kernel#public_methods', '15.3.1.3.38') do
-  assert_equal Array, public_methods.class
-  class Foo
-    def foo
-    end
-  end
-  assert_equal [:foo], Foo.new.public_methods(false)
-end
-
 # Kernel#puts is defined in mruby-print mrbgem. '15.3.1.3.39'
 
 assert('Kernel#raise', '15.3.1.3.40') do
@@ -496,46 +451,13 @@ assert('Kernel#send', '15.3.1.3.44') do
   # test with argument
   assert_true send(:respond_to?, :nil?)
   # test without argument and without block
-  assert_equal send(:public_methods).class, Array
-end
-
-assert('Kernel#singleton_methods', '15.3.1.3.45') do
-  assert_equal singleton_methods.class, Array
+  assert_equal send(:to_s).class, String
 end
 
 assert('Kernel#to_s', '15.3.1.3.46') do
   assert_equal to_s.class, String
 end
 
-assert('Kernel#to_s on primitives') do
-  begin
-    Fixnum.alias_method :to_s_, :to_s
-    Fixnum.remove_method :to_s
-
-    assert_nothing_raised do
-      # segfaults if mrb_cptr is used
-      1.to_s
-    end
-  ensure
-    Fixnum.alias_method :to_s, :to_s_
-    Fixnum.remove_method :to_s_
-  end
-end
-
-assert('Kernel.local_variables', '15.3.1.2.7') do
-  a, b = 0, 1
-  a += b
-
-  vars = Kernel.local_variables.sort
-  assert_equal [:a, :b, :vars], vars
-
-  assert_equal [:a, :b, :c, :vars], Proc.new { |a, b|
-    c = 2
-    # Kernel#local_variables: 15.3.1.3.28
-    local_variables.sort
-  }.call(-1, -2)
-end
-
 assert('Kernel#!=') do
   str1 = "hello"
   str2 = str1
@@ -585,15 +507,6 @@ assert('Kernel#global_variables') do
   end
 end
 
-assert('Kernel#define_singleton_method') do
-  o = Object.new
-  ret = o.define_singleton_method(:test_method) do
-    :singleton_method_ok
-  end
-  assert_equal :test_method, ret
-  assert_equal :singleton_method_ok, o.test_method
-end
-
 assert('stack extend') do
   def recurse(count, stop)
     return count if count > stop
diff --git a/test/t/module.rb b/test/t/module.rb
index fb82fc934..fda375721 100644
--- a/test/t/module.rb
+++ b/test/t/module.rb
@@ -3,7 +3,7 @@
 
 def labeled_module(name, &block)
   Module.new do
-    singleton_class.class_eval do
+    (class <<self; self end).class_eval do
       define_method(:to_s) { name }
       alias_method :inspect, :to_s
     end
@@ -13,7 +13,7 @@ end
 
 def labeled_class(name, supklass = Object, &block)
   Class.new(supklass) do
-    singleton_class.class_eval do
+    (class <<self; self end).class_eval do
       define_method(:to_s) { name }
       alias_method :inspect, :to_s
     end
@@ -27,24 +27,9 @@ end
 
 # TODO not implemented ATM assert('Module.constants', '15.2.2.3.1') do
 
-# TODO not implemented ATM assert('Module.nesting', '15.2.2.3.2') do
-
-assert('Module.nesting', '15.2.2.2.2') do
-  module Test4ModuleNesting
-    module Test4ModuleNesting2
-      assert_equal [Test4ModuleNesting2, Test4ModuleNesting],
-                   Module.nesting
-    end
-  end
-  module Test4ModuleNesting::Test4ModuleNesting2
-    assert_equal [Test4ModuleNesting::Test4ModuleNesting2], Module.nesting
-  end
-end
-
 assert('Module#ancestors', '15.2.2.4.9') do
   class Test4ModuleAncestors
   end
-  sc = Test4ModuleAncestors.singleton_class
   r = String.ancestors
 
   assert_equal Array, r.class
@@ -213,56 +198,9 @@ assert('Module#class_eval', '15.2.2.4.15') do
     def method1
     end
   end
-  r = Test4ClassEval.instance_methods
-
   assert_equal 11, Test4ClassEval.class_eval{ @a }
   assert_equal 12, Test4ClassEval.class_eval{ @b }
-  assert_equal Array, r.class
-  assert_true r.include?(:method1)
-end
-
-assert('Module#class_variable_defined?', '15.2.2.4.16') do
-  class Test4ClassVariableDefined
-    @@cv = 99
-  end
-
-  assert_true Test4ClassVariableDefined.class_variable_defined?(:@@cv)
-  assert_false Test4ClassVariableDefined.class_variable_defined?(:@@noexisting)
-end
-
-assert('Module#class_variable_get', '15.2.2.4.17') do
-  class Test4ClassVariableGet
-    @@cv = 99
-  end
-
-  assert_equal 99, Test4ClassVariableGet.class_variable_get(:@@cv)
-end
-
-assert('Module#class_variable_set', '15.2.2.4.18') do
-  class Test4ClassVariableSet
-    @@foo = 100
-    def foo
-      @@foo
-    end
-  end
-
-  assert_true Test4ClassVariableSet.class_variable_set(:@@cv, 99)
-  assert_true Test4ClassVariableSet.class_variable_set(:@@foo, 101)
-  assert_true Test4ClassVariableSet.class_variables.include? :@@cv
-  assert_equal 99, Test4ClassVariableSet.class_variable_get(:@@cv)
-  assert_equal 101, Test4ClassVariableSet.new.foo
-end
-
-assert('Module#class_variables', '15.2.2.4.19') do
-  class Test4ClassVariables1
-    @@var1 = 1
-  end
-  class Test4ClassVariables2 < Test4ClassVariables1
-    @@var2 = 2
-  end
-
-  assert_equal [:@@var1], Test4ClassVariables1.class_variables
-  assert_equal [:@@var2, :@@var1], Test4ClassVariables2.class_variables
+  assert_equal true, Test4ClassEval.new.respond_to?(:method1)
 end
 
 assert('Module#const_defined?', '15.2.2.4.20') do
@@ -288,16 +226,6 @@ assert('Module#const_get', '15.2.2.4.21') do
   assert_raise(NameError){ Test4ConstGet.const_get("I_DO_NOT_EXIST::ME_NEITHER") }
 end
 
-assert('Module#const_missing', '15.2.2.4.22') do
-  module Test4ConstMissing
-    def self.const_missing(sym)
-      42 # the answer to everything
-    end
-  end
-
-  assert_equal 42, Test4ConstMissing.const_get(:ConstDoesntExist)
-end
-
 assert('Module#const_set', '15.2.2.4.23') do
   module Test4ConstSet
     Const4Test4ConstSet = 42
@@ -307,19 +235,36 @@ assert('Module#const_set', '15.2.2.4.23') do
   assert_equal 23, Test4ConstSet.const_get(:Const4Test4ConstSet)
 end
 
-assert('Module#constants', '15.2.2.4.24') do
-  $n = []
-  module TestA
-    C = 1
+assert('Module#remove_const', '15.2.2.4.40') do
+  module Test4RemoveConst
+    ExistingConst = 23
   end
-  class TestB
-    include TestA
-    C2 = 1
-    $n = constants.sort
+
+  result = Test4RemoveConst.module_eval { remove_const :ExistingConst }
+
+  name_error = false
+  begin
+    Test4RemoveConst.module_eval { remove_const :NonExistingConst }
+  rescue NameError
+    name_error = true
+  end
+
+  # Constant removed from Module
+  assert_false Test4RemoveConst.const_defined? :ExistingConst
+  # Return value of binding
+  assert_equal 23, result
+  # Name Error raised when Constant doesn't exist
+  assert_true name_error
+end
+
+assert('Module#const_missing', '15.2.2.4.22') do
+  module Test4ConstMissing
+    def self.const_missing(sym)
+      42 # the answer to everything
+    end
   end
 
-  assert_equal [ :C ], TestA.constants
-  assert_equal [ :C, :C2 ], $n
+  assert_equal 42, Test4ConstMissing.const_get(:ConstDoesntExist)
 end
 
 assert('Module#include', '15.2.2.4.27') do
@@ -366,48 +311,16 @@ assert('Module#included', '15.2.2.4.29') do
   assert_equal Test4Included2, Test4Included2.const_get(:Const4Included2)
 end
 
-assert('Module#included_modules', '15.2.2.4.30') do
-  module Test4includedModules
-  end
-  module Test4includedModules2
-    include Test4includedModules
-  end
-  r = Test4includedModules2.included_modules
-
-  assert_equal Array, r.class
-  assert_true r.include?(Test4includedModules)
-end
-
 assert('Module#initialize', '15.2.2.4.31') do
   assert_kind_of Module, Module.new
   mod = Module.new { def hello; "hello"; end }
-  assert_equal [:hello], mod.instance_methods
+  cls = Class.new{include mod}
+  assert_true cls.new.respond_to?(:hello)
   a = nil
   mod = Module.new { |m| a = m }
   assert_equal mod, a
 end
 
-assert('Module#instance_methods', '15.2.2.4.33') do
-  module Test4InstanceMethodsA
-    def method1()  end
-  end
-  class Test4InstanceMethodsB
-    def method2()  end
-  end
-  class Test4InstanceMethodsC < Test4InstanceMethodsB
-    def method3()  end
-  end
-
-  r = Test4InstanceMethodsC.instance_methods(true)
-
-  assert_equal [:method1], Test4InstanceMethodsA.instance_methods
-  assert_equal [:method2], Test4InstanceMethodsB.instance_methods(false)
-  assert_equal [:method3], Test4InstanceMethodsC.instance_methods(false)
-  assert_equal Array, r.class
-  assert_true r.include?(:method3)
-  assert_true r.include?(:method2)
-end
-
 assert('Module#method_defined?', '15.2.2.4.34') do
   module Test4MethodDefined
     module A
@@ -431,7 +344,6 @@ assert('Module#method_defined?', '15.2.2.4.34') do
   assert_false Test4MethodDefined::C.method_defined? "method4"
 end
 
-
 assert('Module#module_eval', '15.2.2.4.35') do
   module Test4ModuleEval
     @a = 11
@@ -442,55 +354,6 @@ assert('Module#module_eval', '15.2.2.4.35') do
   assert_equal 12, Test4ModuleEval.module_eval{ @b }
 end
 
-assert('Module#remove_class_variable', '15.2.2.4.39') do
-  class Test4RemoveClassVariable
-    @@cv = 99
-  end
-
-  assert_equal 99, Test4RemoveClassVariable.remove_class_variable(:@@cv)
-  assert_false Test4RemoveClassVariable.class_variables.include? :@@cv
-end
-
-assert('Module#remove_const', '15.2.2.4.40') do
-  module Test4RemoveConst
-    ExistingConst = 23
-  end
-
-  result = Test4RemoveConst.module_eval { remove_const :ExistingConst }
-
-  name_error = false
-  begin
-    Test4RemoveConst.module_eval { remove_const :NonExistingConst }
-  rescue NameError
-    name_error = true
-  end
-
-  # Constant removed from Module
-  assert_false Test4RemoveConst.const_defined? :ExistingConst
-  # Return value of binding
-  assert_equal 23, result
-  # Name Error raised when Constant doesn't exist
-  assert_true name_error
-end
-
-assert('Module#remove_method', '15.2.2.4.41') do
-  module Test4RemoveMethod
-    class Parent
-      def hello
-      end
-     end
-
-     class Child < Parent
-      def hello
-      end
-    end
-  end
-
-  assert_true Test4RemoveMethod::Child.class_eval{ remove_method :hello }
-  assert_true Test4RemoveMethod::Child.instance_methods.include? :hello
-  assert_false Test4RemoveMethod::Child.instance_methods(false).include? :hello
-end
-
 assert('Module#undef_method', '15.2.2.4.42') do
   module Test4UndefMethod
     class Parent
@@ -511,7 +374,6 @@ assert('Module#undef_method', '15.2.2.4.42') do
   assert_true Test4UndefMethod::Parent.new.respond_to?(:hello)
   assert_false Test4UndefMethod::Child.new.respond_to?(:hello)
   assert_false Test4UndefMethod::GrandChild.new.respond_to?(:hello)
-  assert_false Test4UndefMethod::Child.instance_methods(false).include? :hello
 end
 
 # Not ISO specified
@@ -608,41 +470,6 @@ end
     assert_kind_of(b, c.new, bug8357)
   end
 
-  assert('Moduler#prepend + #instance_methods') do
-    bug6655 = '[ruby-core:45915]'
-    assert_equal(Object.instance_methods, Class.new {prepend Module.new}.instance_methods, bug6655)
-  end
-
-  assert 'Module#prepend + #singleton_methods' do
-    o = Object.new
-    o.singleton_class.class_eval {prepend Module.new}
-    assert_equal([], o.singleton_methods)
-  end
-
-  assert 'Module#prepend + #remove_method' do
-    c = Class.new do
-      prepend Module.new { def foo; end }
-    end
-    assert_raise(NameError) do
-      c.class_eval do
-        remove_method(:foo)
-      end
-    end
-    c.class_eval do
-      def foo; end
-    end
-    removed = nil
-    c.singleton_class.class_eval do
-      define_method(:method_removed) {|id| removed = id}
-    end
-    assert_nothing_raised('[Bug #7843]') do
-      c.class_eval do
-        remove_method(:foo)
-      end
-    end
-    assert_equal(:foo, removed)
-  end
-
   assert 'Module#prepend + Class#ancestors' do
     bug6658 = '[ruby-core:45919]'
     m = labeled_module("m")
@@ -683,12 +510,6 @@ end
     assert_equal([m3, m0, m1], m3.ancestors)
   end
 
-  assert 'Module#prepend #instance_methods(false)' do
-    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
-
   assert 'cyclic Module#prepend' do
     bug7841 = '[ruby-core:52205] [Bug #7841]'
     m1 = Module.new
@@ -743,21 +564,6 @@ end
     assert_equal(Test4PrependVisibilityInherited::A, Test4PrependVisibilityInherited::B.new.foo, "#{bug8238}")
   end
 
-  assert 'Module#prepend + #included_modules' do
-    bug8025 = '[ruby-core:53158] [Bug #8025]'
-    mixin = labeled_module("mixin")
-    c = labeled_module("c") {prepend mixin}
-    im = c.included_modules
-    assert_not_include(im, c, bug8025)
-    assert_include(im, mixin, bug8025)
-    c1 = labeled_class("c1") {prepend mixin}
-    c2 = labeled_class("c2", c1)
-    im = c2.included_modules
-    assert_not_include(im, c1, bug8025)
-    assert_not_include(im, c2, bug8025)
-    assert_include(im, mixin, bug8025)
-  end
-
   assert 'Module#prepend super in alias' do
     skip "super does not currently work in aliased methods"
     bug7842 = '[Bug #7842]'