Add mrbgems/mruby-method

from https://github.com/ksss/mruby-method/commit/0837a0b507a5b4cdf8a1f1039ee371cee4e3b7fb

10 files changed, 993 insertions, 0 deletions

diff --git a/mrbgems/mruby-method/.travis.yml b/mrbgems/mruby-method/.travis.yml
new file mode 100644
index 000000000..d7422d568
--- /dev/null
+++ b/mrbgems/mruby-method/.travis.yml
@@ -0,0 +1,17 @@
+language: c
+compiler:
+  - gcc
+  - clang
+before_install:
+  - sudo apt-get -qq update
+install:
+  - sudo apt-get -qq install rake bison git gperf
+before_script:
+  - cd ../
+  - git clone https://github.com/mruby/mruby.git
+  - cd mruby
+  - cp -fp ../mruby-method/.travis_build_config.rb build_config.rb
+script:
+  - ruby minirake all test
+notifications:
+  email: false
diff --git a/mrbgems/mruby-method/.travis_build_config.rb b/mrbgems/mruby-method/.travis_build_config.rb
new file mode 100644
index 000000000..769b98a1b
--- /dev/null
+++ b/mrbgems/mruby-method/.travis_build_config.rb
@@ -0,0 +1,6 @@
+MRuby::Build.new do |conf|
+  toolchain :gcc
+  enable_debug
+  conf.gembox 'default'
+  conf.gem '../mruby-method'
+end
diff --git a/mrbgems/mruby-method/README.md b/mrbgems/mruby-method/README.md
new file mode 100644
index 000000000..dae6c0108
--- /dev/null
+++ b/mrbgems/mruby-method/README.md
@@ -0,0 +1,77 @@
+mruby-method
+===
+
+[![Build Status](https://travis-ci.org/ksss/mruby-method.svg)](https://travis-ci.org/ksss/mruby-method)
+
+A implementetion of class **Method** and **UnboundMethod** for mruby
+
+```ruby
+p Enumerable.instance_method(:find_all).source_location
+#=> ["mruby/mruby/mrblib/enum.rb", 148]
+```
+
+![https://raw.githubusercontent.com/ksss/mruby-method/master/find_all.png](https://raw.githubusercontent.com/ksss/mruby-method/master/find_all.png)
+
+# Installation
+
+in build_config.rb
+
+```ruby
+MRuby::Build.new do |conf|
+  enable_debug
+
+  conf.gem :mgem => "mruby-method"
+  # or
+  conf.gem :github => "ksss/mruby-method"
+end
+```
+
+# Note
+
+`source_location` method need this configuration in build_config.rb
+
+```ruby
+MRuby::Build.new do |conf|
+  enable_debug
+end
+```
+
+# Supported Methods
+
+## Kernel
+
+- `Kernel#method`
+- `Kernel#singleton_method`
+
+## Module
+
+- `Module#instance_method`
+
+## Method class
+
+- `Method#name`
+- `Method#call`
+- `Method#super_method`
+- `Method#arity`
+- `Method#unbind`
+- `Method#[]`
+- `Method#owner`
+- `Method#receiver`
+- `Method#parameters`
+- `Method#source_location`
+- `Method#to_proc`
+
+## UnboundMethod class
+
+- `UnboundMethod#name`
+- `UnboundMethod#bind`
+- `UnboundMethod#super_method`
+- `UnboundMethod#arity`
+- `UnboundMethod#owner`
+- `UnboundMethod#parameters`
+- `UnboundMethod#source_location`
+
+# See also
+
+- https://ruby-doc.org/core-2.3.3/Method.html
+- https://ruby-doc.org/core-2.3.3/UnboundMethod.html
diff --git a/mrbgems/mruby-method/find_all.png b/mrbgems/mruby-method/find_all.png
new file mode 100644
index 000000000..b09b91ee8
--- /dev/null
+++ b/mrbgems/mruby-method/find_all.png
diff --git a/mrbgems/mruby-method/mrbgem.rake b/mrbgems/mruby-method/mrbgem.rake
new file mode 100644
index 000000000..dca0c3af8
--- /dev/null
+++ b/mrbgems/mruby-method/mrbgem.rake
@@ -0,0 +1,7 @@
+MRuby::Gem::Specification.new('mruby-method') do |spec|
+  spec.license = 'MIT'
+  spec.author  = 'mruby developers'
+  spec.summary = 'Method and UnboundMethod class'
+
+  spec.add_dependency('mruby-proc-ext', :core => 'mruby-proc-ext')
+end
diff --git a/mrbgems/mruby-method/mrblib/kernel.rb b/mrbgems/mruby-method/mrblib/kernel.rb
new file mode 100644
index 000000000..b2ebd45ea
--- /dev/null
+++ b/mrbgems/mruby-method/mrblib/kernel.rb
@@ -0,0 +1,9 @@
+module Kernel
+  def singleton_method(name)
+    m = method(name)
+    if m.owner != singleton_class
+      raise NameError, "undefined method `#{name}' for class `#{singleton_class}'"
+    end
+    m
+  end
+end
diff --git a/mrbgems/mruby-method/mrblib/method.rb b/mrbgems/mruby-method/mrblib/method.rb
new file mode 100644
index 000000000..5de0afdf7
--- /dev/null
+++ b/mrbgems/mruby-method/mrblib/method.rb
@@ -0,0 +1,20 @@
+class Method
+  def to_proc
+    m = self
+    lambda { |*args, &b|
+      m.call(*args, &b)
+    }
+  end
+
+  def owner
+    @owner
+  end
+
+  def receiver
+    @recv
+  end
+
+  def name
+    @name
+  end
+end
diff --git a/mrbgems/mruby-method/mrblib/unbound_method.rb b/mrbgems/mruby-method/mrblib/unbound_method.rb
new file mode 100644
index 000000000..1d3acf3fa
--- /dev/null
+++ b/mrbgems/mruby-method/mrblib/unbound_method.rb
@@ -0,0 +1,9 @@
+class UnboundMethod
+  def owner
+    @owner
+  end
+
+  def name
+    @name
+  end
+end
diff --git a/mrbgems/mruby-method/src/method.c b/mrbgems/mruby-method/src/method.c
new file mode 100644
index 000000000..a40faa5ef
--- /dev/null
+++ b/mrbgems/mruby-method/src/method.c
@@ -0,0 +1,423 @@
+#include "mruby.h"
+#include "mruby/array.h"
+#include "mruby/data.h"
+#include "mruby/class.h"
+#include "mruby/variable.h"
+#include "mruby/proc.h"
+#include "mruby/string.h"
+#include <alloca.h>
+
+static struct RObject *
+method_object_alloc(mrb_state *mrb, struct RClass *mclass)
+{
+  return (struct RObject*)mrb_obj_alloc(mrb, MRB_TT_OBJECT, mclass);
+}
+
+static mrb_value
+unbound_method_bind(mrb_state *mrb, mrb_value self)
+{
+  struct RObject *me;
+  mrb_value owner = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@owner"));
+  mrb_value name = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@name"));
+  mrb_value proc = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "proc"));
+  mrb_value klass = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@klass"));
+  mrb_value recv;
+
+  mrb_get_args(mrb, "o", &recv);
+
+  if (mrb_type(owner) != MRB_TT_MODULE &&
+      mrb_class_ptr(owner) != mrb_obj_class(mrb, recv) &&
+      !mrb_obj_is_kind_of(mrb, recv, mrb_class_ptr(owner))) {
+        if (mrb_type(owner) == MRB_TT_SCLASS) {
+          mrb_raise(mrb, E_TYPE_ERROR, "singleton method called for a different object");
+        } else {
+          const char *s = mrb_class_name(mrb, mrb_class_ptr(owner));
+          mrb_raisef(mrb, E_TYPE_ERROR, "bind argument must be an instance of %S", mrb_str_new_static(mrb, s, strlen(s)));
+        }
+  }
+  me = method_object_alloc(mrb, mrb_class_get(mrb, "Method"));
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@owner"), owner);
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@recv"), recv);
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@name"), name);
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "proc"), proc);
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@klass"), klass);
+
+  return mrb_obj_value(me);
+}
+
+#define IV_GET(value, name) mrb_iv_get(mrb, value, mrb_intern_lit(mrb, name))
+static mrb_value
+method_eql(mrb_state *mrb, mrb_value self)
+{
+  mrb_value other, receiver, orig_proc, other_proc;
+  struct RClass *owner, *klass;
+  struct RProc *orig_rproc, *other_rproc;
+
+  mrb_get_args(mrb, "o", &other);
+  if (!mrb_obj_is_instance_of(mrb, other, mrb_class(mrb, self)))
+    return mrb_false_value();
+
+  if (mrb_class(mrb, self) != mrb_class(mrb, other))
+    return mrb_false_value();
+
+  klass = mrb_class_ptr(IV_GET(self, "@klass"));
+  if (klass != mrb_class_ptr(IV_GET(other, "@klass")))
+    return mrb_false_value();
+
+  owner = mrb_class_ptr(IV_GET(self, "@owner"));
+  if (owner != mrb_class_ptr(IV_GET(other, "@owner")))
+    return mrb_false_value();
+
+  receiver = IV_GET(self, "@recv");
+  if (!mrb_obj_equal(mrb, receiver, IV_GET(other, "@recv")))
+    return mrb_false_value();
+
+  orig_proc = IV_GET(self, "proc");
+  other_proc = IV_GET(other, "proc");
+  if (mrb_nil_p(orig_proc) && mrb_nil_p(other_proc)) {
+    if (mrb_symbol(IV_GET(self, "@name")) == mrb_symbol(IV_GET(other, "@name")))
+      return mrb_true_value();
+    else
+      return mrb_false_value();
+  }
+
+  if (mrb_nil_p(orig_proc))
+    return mrb_false_value();
+  if (mrb_nil_p(other_proc))
+    return mrb_false_value();
+
+  orig_rproc = mrb_proc_ptr(orig_proc);
+  other_rproc = mrb_proc_ptr(other_proc);
+  if (MRB_PROC_CFUNC_P(orig_rproc)) {
+    if (!MRB_PROC_CFUNC_P(other_rproc))
+      return mrb_false_value();
+    if (orig_rproc->body.func != other_rproc->body.func)
+      return mrb_false_value();
+  }
+  else {
+    if (MRB_PROC_CFUNC_P(other_rproc))
+      return mrb_false_value();
+    if (orig_rproc->body.irep != other_rproc->body.irep)
+      return mrb_false_value();
+  }
+
+  return mrb_true_value();
+}
+
+#undef IV_GET
+
+static mrb_value
+method_call(mrb_state *mrb, mrb_value self)
+{
+  mrb_value proc = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "proc"));
+  mrb_value name = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@name"));
+  mrb_value recv = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@recv"));
+  struct RClass *owner = mrb_class_ptr(mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@owner")));
+  mrb_int argc, i;
+  mrb_value *argv, ret, block;
+  mrb_sym orig_mid;
+
+  mrb_get_args(mrb, "*&", &argv, &argc, &block);
+  orig_mid = mrb->c->ci->mid;
+  mrb->c->ci->mid = mrb_symbol(name);
+  if (mrb_nil_p(proc)) {
+    mrb_value *missing_argv = (mrb_value*)alloca(sizeof(mrb_value) * (argc + 1));
+    missing_argv[0] = name;
+    for(i = 0; i < argc; i++) {
+      missing_argv[i + 1] = argv[i];
+    }
+    ret = mrb_funcall_argv(mrb, recv, mrb_intern_lit(mrb, "method_missing"), argc + 1, missing_argv);
+  }
+  else if (!mrb_nil_p(block)) {
+    /*
+      workaround since `mrb_yield_with_class` does not support passing block as parameter
+      need new API that initializes `mrb->c->stack[argc+1]` with block passed by argument
+    */
+    ret = mrb_funcall_with_block(mrb, recv, mrb_symbol(name), argc, argv, block);
+  }
+  else {
+    ret = mrb_yield_with_class(mrb, proc, argc, argv, recv, owner);
+  }
+  mrb->c->ci->mid = orig_mid;
+  return ret;
+}
+
+static mrb_value
+method_unbind(mrb_state *mrb, mrb_value self)
+{
+  struct RObject *ume;
+  mrb_value owner = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@owner"));
+  mrb_value name = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@name"));
+  mrb_value proc = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "proc"));
+  mrb_value klass = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@klass"));
+
+  ume = method_object_alloc(mrb, mrb_class_get(mrb, "UnboundMethod"));
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "@owner"), owner);
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "@recv"), mrb_nil_value());
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "@name"), name);
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "proc"), proc);
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "@klass"), klass);
+
+  return mrb_obj_value(ume);
+}
+
+static struct RProc *
+method_search_vm(mrb_state *mrb, struct RClass **cp, mrb_sym mid)
+{
+  mrb_method_t m = mrb_method_search_vm(mrb, cp, mid);
+  if (MRB_METHOD_UNDEF_P(m))
+    return NULL;
+  if (MRB_METHOD_PROC_P(m))
+    return MRB_METHOD_PROC(m);
+  return mrb_proc_new_cfunc(mrb, MRB_METHOD_FUNC(m));
+}
+
+static mrb_value
+method_super_method(mrb_state *mrb, mrb_value self)
+{
+  mrb_value recv = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@recv"));
+  mrb_value klass = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@klass"));
+  mrb_value owner = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@owner"));
+  mrb_value name = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@name"));
+  struct RClass *super, *rklass;
+  struct RProc *proc;
+  struct RObject *me;
+
+  switch (mrb_type(klass)) {
+    case MRB_TT_SCLASS:
+      super = mrb_class_ptr(klass)->super->super;
+      break;
+    case MRB_TT_ICLASS:
+      super = mrb_class_ptr(klass)->super;
+      break;
+    default:
+      super = mrb_class_ptr(owner)->super;
+      break;
+  }
+
+  proc = method_search_vm(mrb, &super, mrb_symbol(name));
+  if (!proc)
+    return mrb_nil_value();
+
+  rklass = super;
+  while (super->tt == MRB_TT_ICLASS)
+    super = super->c;
+
+  me = method_object_alloc(mrb, mrb_obj_class(mrb, self));
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@owner"), mrb_obj_value(super));
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@recv"), recv);
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@name"), name);
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "proc"), mrb_obj_value(proc));
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@klass"), mrb_obj_value(rklass));
+
+  return mrb_obj_value(me);
+}
+
+static mrb_value
+method_arity(mrb_state *mrb, mrb_value self)
+{
+  mrb_value proc = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "proc"));
+  struct RProc *rproc;
+  struct RClass *orig;
+  mrb_value ret;
+
+  if (mrb_nil_p(proc))
+    return mrb_fixnum_value(-1);
+
+  rproc = mrb_proc_ptr(proc);
+  orig = rproc->c;
+  rproc->c = mrb->proc_class;
+  ret = mrb_funcall(mrb, proc, "arity", 0);
+  rproc->c = orig;
+  return ret;
+}
+
+static mrb_value
+method_source_location(mrb_state *mrb, mrb_value self)
+{
+  mrb_value proc = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "proc"));
+  struct RProc *rproc;
+  struct RClass *orig;
+  mrb_value ret;
+
+  if (mrb_nil_p(proc))
+    return mrb_nil_value();
+
+  rproc = mrb_proc_ptr(proc);
+  orig = rproc->c;
+  rproc->c = mrb->proc_class;
+  ret = mrb_funcall(mrb, proc, "source_location", 0);
+  rproc->c = orig;
+  return ret;
+}
+
+static mrb_value
+method_parameters(mrb_state *mrb, mrb_value self)
+{
+  mrb_value proc = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "proc"));
+  struct RProc *rproc;
+  struct RClass *orig;
+  mrb_value ret;
+
+  if (mrb_nil_p(proc)) {
+    mrb_value rest = mrb_symbol_value(mrb_intern_lit(mrb, "rest"));
+    mrb_value arest = mrb_ary_new_from_values(mrb, 1, &rest);
+    return mrb_ary_new_from_values(mrb, 1, &arest);
+  }
+
+  rproc = mrb_proc_ptr(proc);
+  orig = rproc->c;
+  rproc->c = mrb->proc_class;
+  ret = mrb_funcall(mrb, proc, "parameters", 0);
+  rproc->c = orig;
+  return ret;
+}
+
+static mrb_value
+method_to_s(mrb_state *mrb, mrb_value self)
+{
+  mrb_value owner = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@owner"));
+  mrb_value klass = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@klass"));
+  mrb_value name = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@name"));
+  mrb_value str = mrb_str_new_lit(mrb, "#<");
+  struct RClass *rklass;
+
+  mrb_str_cat_cstr(mrb, str, mrb_obj_classname(mrb, self));
+  mrb_str_cat_lit(mrb, str, ": ");
+  rklass = mrb_class_ptr(klass);
+  if (mrb_class_ptr(owner) == rklass) {
+    mrb_str_cat_str(mrb, str, mrb_funcall(mrb, owner, "to_s", 0));
+    mrb_str_cat_lit(mrb, str, "#");
+    mrb_str_cat_str(mrb, str, mrb_funcall(mrb, name, "to_s", 0));
+  }
+  else {
+    mrb_str_cat_cstr(mrb, str, mrb_class_name(mrb, rklass));
+    mrb_str_cat_lit(mrb, str, "(");
+    mrb_str_cat_str(mrb, str, mrb_funcall(mrb, owner, "to_s", 0));
+    mrb_str_cat_lit(mrb, str, ")#");
+    mrb_str_cat_str(mrb, str, mrb_funcall(mrb, name, "to_s", 0));
+  }
+  mrb_str_cat_lit(mrb, str, ">");
+  return str;
+}
+
+static void
+mrb_search_method_owner(mrb_state *mrb, struct RClass *c, mrb_value obj, mrb_sym name, struct RClass **owner, struct RProc **proc, mrb_bool unbound)
+{
+  mrb_value ret;
+  const char *s;
+
+  *owner = c;
+  *proc = method_search_vm(mrb, owner, name);
+  if (!*proc) {
+    if (unbound) {
+      goto name_error;
+    }
+    if (!mrb_respond_to(mrb, obj, mrb_intern_lit(mrb, "respond_to_missing?"))) {
+      goto name_error;
+    }
+    ret = mrb_funcall(mrb, obj, "respond_to_missing?", 2, mrb_symbol_value(name), mrb_true_value());
+    if (!mrb_test(ret)) {
+      goto name_error;
+    }
+    *owner = c;
+  }
+
+  while ((*owner)->tt == MRB_TT_ICLASS)
+    *owner = (*owner)->c;
+
+  return;
+
+name_error:
+  s = mrb_class_name(mrb, c);
+  mrb_raisef(
+    mrb, E_NAME_ERROR,
+    "undefined method `%S' for class `%S'",
+    mrb_sym2str(mrb, name),
+    mrb_str_new_static(mrb, s, strlen(s))
+  );
+}
+
+static mrb_value
+mrb_kernel_method(mrb_state *mrb, mrb_value self)
+{
+  struct RClass *owner;
+  struct RProc *proc;
+  struct RObject *me;
+  mrb_sym name;
+
+  mrb_get_args(mrb, "n", &name);
+
+  mrb_search_method_owner(mrb, mrb_class(mrb, self), self, name, &owner, &proc, FALSE);
+
+  me = method_object_alloc(mrb, mrb_class_get(mrb, "Method"));
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@owner"), mrb_obj_value(owner));
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@recv"), self);
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@name"), mrb_symbol_value(name));
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "proc"), proc ? mrb_obj_value(proc) : mrb_nil_value());
+  mrb_obj_iv_set(mrb, me, mrb_intern_lit(mrb, "@klass"), mrb_obj_value(mrb_class(mrb, self)));
+
+  return mrb_obj_value(me);
+}
+
+static mrb_value
+mrb_module_instance_method(mrb_state *mrb, mrb_value self)
+{
+  struct RClass *owner;
+  struct RProc *proc;
+  struct RObject *ume;
+  mrb_sym name;
+
+  mrb_get_args(mrb, "n", &name);
+
+  mrb_search_method_owner(mrb, mrb_class_ptr(self), self, name, &owner, &proc, TRUE);
+
+  ume = method_object_alloc(mrb, mrb_class_get(mrb, "UnboundMethod"));
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "@owner"), mrb_obj_value(owner));
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "@recv"), mrb_nil_value());
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "@name"), mrb_symbol_value(name));
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "proc"), proc ? mrb_obj_value(proc) : mrb_nil_value());
+  mrb_obj_iv_set(mrb, ume, mrb_intern_lit(mrb, "@klass"), self);
+
+  return mrb_obj_value(ume);
+}
+
+void
+mrb_mruby_method_gem_init(mrb_state* mrb)
+{
+  struct RClass *unbound_method = mrb_define_class(mrb, "UnboundMethod", mrb->object_class);
+  struct RClass *method = mrb_define_class(mrb, "Method", mrb->object_class);
+
+  mrb_undef_class_method(mrb, unbound_method, "new");
+  mrb_define_method(mrb, unbound_method, "bind", unbound_method_bind, MRB_ARGS_REQ(1));
+  mrb_define_method(mrb, unbound_method, "super_method", method_super_method, MRB_ARGS_NONE());
+  mrb_define_method(mrb, unbound_method, "==", method_eql, MRB_ARGS_REQ(1));
+  mrb_alias_method(mrb, unbound_method, mrb_intern_lit(mrb, "eql?"), mrb_intern_lit(mrb, "=="));
+  mrb_define_method(mrb, unbound_method, "to_s", method_to_s, MRB_ARGS_NONE());
+  mrb_define_method(mrb, unbound_method, "inspect", method_to_s, MRB_ARGS_NONE());
+  mrb_define_method(mrb, unbound_method, "arity", method_arity, MRB_ARGS_NONE());
+  mrb_define_method(mrb, unbound_method, "source_location", method_source_location, MRB_ARGS_NONE());
+  mrb_define_method(mrb, unbound_method, "parameters", method_parameters, MRB_ARGS_NONE());
+
+  mrb_undef_class_method(mrb, method, "new");
+  mrb_define_method(mrb, method, "==", method_eql, MRB_ARGS_REQ(1));
+  mrb_alias_method(mrb, method, mrb_intern_lit(mrb, "eql?"), mrb_intern_lit(mrb, "=="));
+  mrb_define_method(mrb, method, "to_s", method_to_s, MRB_ARGS_NONE());
+  mrb_define_method(mrb, method, "inspect", method_to_s, MRB_ARGS_NONE());
+  mrb_define_method(mrb, method, "call", method_call, MRB_ARGS_ANY());
+  mrb_alias_method(mrb, method, mrb_intern_lit(mrb, "[]"), mrb_intern_lit(mrb, "call"));
+  mrb_define_method(mrb, method, "unbind", method_unbind, MRB_ARGS_NONE());
+  mrb_define_method(mrb, method, "super_method", method_super_method, MRB_ARGS_NONE());
+  mrb_define_method(mrb, method, "arity", method_arity, MRB_ARGS_NONE());
+  mrb_define_method(mrb, method, "source_location", method_source_location, MRB_ARGS_NONE());
+  mrb_define_method(mrb, method, "parameters", method_parameters, MRB_ARGS_NONE());
+
+  mrb_define_method(mrb, mrb->kernel_module, "method", mrb_kernel_method, MRB_ARGS_REQ(1));
+
+  mrb_define_method(mrb, mrb->module_class, "instance_method", mrb_module_instance_method, MRB_ARGS_REQ(1));
+}
+
+void
+mrb_mruby_method_gem_final(mrb_state* mrb)
+{
+}
diff --git a/mrbgems/mruby-method/test/method.rb b/mrbgems/mruby-method/test/method.rb
new file mode 100644
index 000000000..b229a4560
--- /dev/null
+++ b/mrbgems/mruby-method/test/method.rb
@@ -0,0 +1,425 @@
+class Base
+  def foo() :base end
+end
+
+class Derived < Base
+  def foo() :derived end
+end
+
+class Interpreter
+  attr_accessor :ret
+
+  def do_a() @ret += "there, "; end
+  def do_d() @ret += "Hello ";  end
+  def do_e() @ret += "!\n";     end
+  def do_v() @ret += "Dave";    end
+  Dispatcher = {
+    "a" => instance_method(:do_a),
+    "d" => instance_method(:do_d),
+    "e" => instance_method(:do_e),
+    "v" => instance_method(:do_v)
+  }
+  def interpret(string)
+    @ret = ""
+    string.each_char {|b| Dispatcher[b].bind(self).call }
+  end
+end
+
+assert 'demo' do
+  interpreter = Interpreter.new
+  interpreter.interpret('dave')
+  assert_equal "Hello there, Dave!\n", interpreter.ret
+end
+
+assert 'Method#arity' do
+  Class.new {
+    attr_accessor :done
+    def initialize; @done = false; end
+    def m0() end
+    def m1(a) end
+    def m2(a, b) end
+    def mo1(a = nil, &b) end
+    def mo2(a, b = nil) end
+    def mo3(*a) end
+    def mo4(a, *b, &c) end
+    def mo5(a, *b, c) end
+    def mo6(a, *b, c, &d) end
+    def mo7(a, b = nil, *c, d, &e) end
+    def ma1((a), &b) nil && a end
+
+    def run
+      assert_equal(0, method(:m0).arity)
+      assert_equal(1, method(:m1).arity)
+      assert_equal(2, method(:m2).arity)
+      assert_equal(-1, method(:mo1).arity)
+      assert_equal(-2, method(:mo2).arity)
+      assert_equal(-1, method(:mo3).arity)
+      assert_equal(-2, method(:mo4).arity)
+      assert_equal(-3, method(:mo5).arity)
+      assert_equal(-3, method(:mo6).arity)
+      assert_equal(-3, method(:mo7).arity)
+      assert_equal(1, method(:ma1).arity)
+
+      assert_equal(-1, method(:__send__).arity)
+      assert_equal(-1, method(:nothing).arity)
+    end
+
+    def respond_to_missing?(m, b)
+      m == :nothing
+    end
+  }.new.run
+end
+
+assert 'Method and UnboundMethod should not be have a `new` method' do
+  assert_raise(NoMethodError){ Method.new }
+  assert_raise(NoMethodError){ UnboundMethod.new }
+end
+
+assert 'instance' do
+  assert_kind_of Method, 1.method(:+)
+  assert_kind_of UnboundMethod, Fixnum.instance_method(:+)
+end
+
+assert 'Method#call' do
+  assert_equal 3, 1.method(:+).call(2)
+  assert_equal "ab", "a".method(:+)["b"]
+  klass = Class.new {
+    def foo; 42; end
+  }
+  klass2 = Class.new(klass) {
+    def foo; super; end
+  }
+  assert_equal 42, klass2.new.method(:foo).call
+
+  i = Class.new {
+   def bar
+     yield 3
+   end
+  }.new
+  assert_raise(LocalJumpError) { i.method(:bar).call }
+  assert_equal 3, i.method(:bar).call { |i| i }
+end
+
+assert 'Method#call for regression' do
+  obj = BasicObject.new
+  def obj.foo
+    :ok
+  end
+  assert_equal :ok, Kernel.instance_method(:send).bind(obj).call(:foo), "https://github.com/ksss/mruby-method/issues/4"
+end
+
+assert 'Method#call with undefined method' do
+  c = Class.new {
+    attr_accessor :m, :argv
+    def respond_to_missing?(m, b)
+      m == :foo
+    end
+
+    def method_missing(m, *argv)
+      @m = m
+      @argv = argv
+      super
+    end
+  }
+  cc = c.new
+  assert_raise(NameError) { cc.method(:nothing) }
+  assert_kind_of Method, cc.method(:foo)
+  assert_raise(NoMethodError) { cc.method(:foo).call(:arg1, :arg2) }
+  assert_equal :foo, cc.m
+  assert_equal [:arg1, :arg2], cc.argv
+
+  cc = c.new
+  m = cc.method(:foo)
+  c.class_eval do
+    def foo
+      :ng
+    end
+  end
+  assert_raise(NoMethodError) { m.call(:arg1, :arg2) }
+end
+
+assert 'Method#source_location' do
+  skip if proc{}.source_location.nil?
+
+  filename = __FILE__
+  klass = Class.new
+
+  lineno = __LINE__ + 1
+  klass.define_method(:find_me_if_you_can) {}
+  assert_equal [filename, lineno], klass.new.method(:find_me_if_you_can).source_location
+
+  lineno = __LINE__ + 1
+  klass.define_singleton_method(:s_find_me_if_you_can) {}
+  assert_equal [filename, lineno], klass.method(:s_find_me_if_you_can).source_location
+
+  klass = Class.new { def respond_to_missing?(m, b); m == :nothing; end }
+  assert_nil klass.new.method(:nothing).source_location
+end
+
+assert 'UnboundMethod#source_location' do
+  skip if proc{}.source_location.nil?
+
+  filename = __FILE__
+  klass = Class.new {
+    def respond_to_missing?(m, b)
+      m == :nothing
+    end
+  }
+
+  lineno = __LINE__ + 1
+  klass.define_method(:find_me_if_you_can) {}
+  assert_equal [filename, lineno], klass.instance_method(:find_me_if_you_can).source_location
+  assert_nil klass.new.method(:nothing).unbind.source_location
+end
+
+assert 'Method#parameters' do
+  klass = Class.new {
+    def foo(a, b=nil, *c) end
+    def respond_to_missing?(m, b)
+      m == :missing
+    end
+  }
+  assert_equal [[:req, :a], [:opt, :b], [:rest, :c]], klass.new.method(:foo).parameters
+  assert_equal [[:rest]], klass.new.method(:missing).parameters
+end
+
+assert 'UnboundMethod#parameters' do
+  klass = Class.new {
+    def foo(a, b=nil, *c) end
+    def respond_to_missing?(m, b)
+      m == :nothing
+    end
+  }
+  assert_equal [[:req, :a], [:opt, :b], [:rest, :c]], klass.instance_method(:foo).parameters
+  assert_equal [[:rest]], klass.new.method(:nothing).unbind.parameters
+end
+
+assert 'Method#to_proc' do
+  m = 3.method(:+)
+  assert_kind_of Proc, m.to_proc
+  assert_equal 7, m.call(4)
+
+  o = Object.new
+  def o.foo(a, b=nil, *c)
+    [a, b, c]
+  end
+  assert_equal [:bar, nil, []], o.method(:foo).to_proc.call(:bar)
+#  We can fix this issue but leave until the problem
+#  assert_equal o.method(:foo).arity, o.method(:foo).to_proc.arity
+
+  def o.bar
+    yield 39
+  end
+  assert_equal 42, o.bar(&3.method(:+))
+end
+
+assert 'to_s' do
+  o = Object.new
+  def o.foo; end
+  m = o.method(:foo)
+  assert_equal("#<UnboundMethod: #{ class << o; self; end.inspect }#foo>", m.unbind.inspect)
+
+  c = Class.new
+  c.class_eval { def foo; end; }
+  m = c.new.method(:foo)
+  assert_equal("#<Method: #{ c.inspect }#foo>", m.inspect)
+  m = c.instance_method(:foo)
+  assert_equal("#<UnboundMethod: #{ c.inspect }#foo>", m.inspect)
+end
+
+assert 'owner' do
+  c = Class.new do
+    def foo; end
+    def self.bar; end
+  end
+  m = Module.new do
+    def baz; end
+  end
+  c.include(m)
+  c2 = Class.new(c)
+
+  assert_equal(c, c.instance_method(:foo).owner)
+  assert_equal(c, c2.instance_method(:foo).owner)
+
+  assert_equal(c, c.new.method(:foo).owner)
+  assert_equal(c, c2.new.method(:foo).owner)
+  assert_equal(c.singleton_class, c2.method(:bar).owner)
+end
+
+assert 'owner missing' do
+  c = Class.new do
+    def respond_to_missing?(name, bool)
+      name == :foo
+    end
+  end
+  c2 = Class.new(c)
+  assert_equal(c, c.new.method(:foo).owner)
+  assert_equal(c2, c2.new.method(:foo).owner)
+end
+
+assert 'receiver name owner' do
+  o = Object.new
+  def o.foo; end
+  m = o.method(:foo)
+  assert_equal(o, m.receiver)
+  assert_equal(:foo, m.name)
+  assert_equal(class << o; self; end, m.owner)
+  assert_equal(:foo, m.unbind.name)
+  assert_equal(class << o; self; end, m.unbind.owner)
+end
+
+assert 'Method#unbind' do
+  assert_equal(:derived, Derived.new.foo)
+  um = Derived.new.method(:foo).unbind
+  assert_kind_of(UnboundMethod, um)
+  Derived.class_eval do
+    def foo() :changed end
+  end
+  assert_equal(:changed, Derived.new.foo)
+  assert_equal(:changed, Derived.new.foo{})
+  assert_equal(:derived, um.bind(Derived.new).call)
+  assert_raise(TypeError) do
+    um.bind(Base.new)
+  end
+
+  # TODO:
+  #  Block passed method not handled correctly with workaround.
+  #  See comment near `mrb_funcall_with_block` for detail.
+  # assert_equal(:derived, um.bind(Derived.new).call{})
+end
+
+assert 'Kernel#method' do
+  c1 = Class.new {
+    def foo; :foo; end
+  }
+  o = c1.new
+  assert_kind_of Method, o.method(:foo)
+  assert_kind_of Method, o.method('foo')
+  assert_raise(TypeError) { o.method(nil) }
+  assert_raise(NameError) { o.method('bar') }
+  assert_raise(NameError) { o.method(:bar) }
+end
+
+assert "Module#instance_method" do
+  assert_kind_of UnboundMethod, Object.instance_method(:object_id)
+  assert_raise(NameError) { Object.instance_method(:nothing) }
+  c = Class.new {
+    def respond_to_missing?(m, b)
+      false
+    end
+  }
+  assert_raise(NameError) { c.instance_method(:nothing) }
+end
+
+assert 'Kernel#singleton_method' do
+  c1 = Class.new {
+    def foo; :foo; end
+  }
+  o = c1.new
+  def o.bar; :bar; end
+  assert_kind_of Method, o.method(:foo)
+  assert_raise(NameError) { o.singleton_method(:foo) }
+  assert_kind_of Method, o.singleton_method(:bar)
+  assert_raise(TypeError) { o.singleton_method(nil) }
+  m = assert_nothing_raised(NameError) { break o.singleton_method(:bar) }
+  assert_equal(:bar, m.call)
+end
+
+assert 'Method#super_method' do
+  o = Derived.new
+  m = o.method(:foo).super_method
+  assert_equal(Base, m.owner)
+  assert_true(o.equal? m.receiver)
+  assert_equal(:foo, m.name)
+  assert_nil(m.super_method)
+
+  c = Class.new {
+    def foo; end
+  }
+  o = c.new
+  o.extend Module.new {
+    def foo; end
+  }
+  assert_equal c, o.method(:foo).super_method.owner
+  assert_equal :foo, o.method(:foo).super_method.name
+  assert_equal o, o.method(:foo).super_method.receiver
+end
+
+assert 'Method#==' do
+  o = Object.new
+  class << o
+    def foo; end
+  end
+  assert_not_equal(o.method(:foo), nil)
+  m = o.method(:foo)
+  def m.foo; end
+  # TODO: assert_not_equal(o.method(:foo), m)
+  assert_equal(o.method(:foo), o.method(:foo))
+  # TODO: assert_false(o.method(:foo).eql? m)
+  assert_true(o.method(:foo).eql? o.method(:foo))
+
+  assert_false(0.method(:+) == 1.method(:+))
+  assert_false(0.method(:+) == 0.method(:-))
+  a = 0.method(:+)
+  assert_true(a.method(:==) == a.method(:eql?))
+end
+
+assert "Method#initialize_copy" do
+  c = Class.new {
+    def foo
+    end
+  }.new
+  m1 = c.method(:foo)
+  m2 = m1.clone
+  assert_equal(m1, m2)
+end
+
+assert 'UnboundMethod#arity' do
+  c = Class.new {
+    def foo(a, b)
+    end
+
+    def respond_to_missing?(m, b)
+      m == :nothing
+    end
+  }
+  assert_equal 2, c.instance_method(:foo).arity
+  assert_equal(-1, c.new.method(:nothing).unbind.arity)
+end
+
+assert 'UnboundMethod#==' do
+  assert_false(Fixnum.instance_method(:+) == Fixnum.instance_method(:-))
+  assert_true(Fixnum.instance_method(:+) == Fixnum.instance_method(:+))
+  assert_false(Fixnum.instance_method(:+) == Float.instance_method(:+))
+  assert_true(UnboundMethod.instance_method(:==) == UnboundMethod.instance_method(:eql?))
+end
+
+assert 'UnboundMethod#super_method' do
+  m = Derived.instance_method(:foo)
+  m = m.super_method
+  assert_equal(Base.instance_method(:foo), m)
+  assert_nil(m.super_method)
+
+  m = Object.instance_method(:object_id)
+  assert_nil(m.super_method)
+end
+
+assert 'UnboundMethod#bind' do
+  m = Module.new{ def meth() :meth end }.instance_method(:meth)
+  assert_raise(ArgumentError) { m.bind }
+  assert_kind_of Method, m.bind(1)
+  assert_kind_of Method, m.bind(:sym)
+  assert_kind_of Method, m.bind(Object.new)
+  assert_equal(:meth, m.bind(1).call)
+  assert_equal(:meth, m.bind(:sym).call)
+  assert_equal(:meth, m.bind(Object.new).call)
+  sc = Class.new {
+    class << self
+      def foo
+      end
+    end
+  }.singleton_class
+  assert_raise(TypeError) { sc.instance_method(:foo).bind([]) }
+  assert_raise(TypeError) { Array.instance_method(:each).bind(1) }
+  assert_kind_of Method, Object.instance_method(:object_id).bind(Object.new)
+end