4 files changed, 37 insertions, 29 deletions

diff --git a/mrbgems/mruby-method/mrblib/kernel.rb b/mrbgems/mruby-method/mrblib/kernel.rb
index 2efc93f37..eb17df5a6 100644
--- a/mrbgems/mruby-method/mrblib/kernel.rb
+++ b/mrbgems/mruby-method/mrblib/kernel.rb
@@ -3,7 +3,7 @@ module Kernel
     m = method(name)
     sc = (class <<self; self; end)
     if m.owner != sc
-      raise NameError, "undefined method `#{name}' for class `#{sc}'"
+      raise NameError, "undefined method '#{name}' for class '#{sc}'"
     end
     m
   end
diff --git a/mrbgems/mruby-method/mrblib/method.rb b/mrbgems/mruby-method/mrblib/method.rb
index 5de0afdf7..f7cefa2e5 100644
--- a/mrbgems/mruby-method/mrblib/method.rb
+++ b/mrbgems/mruby-method/mrblib/method.rb
@@ -17,4 +17,12 @@ class Method
   def name
     @name
   end
+
+  def <<(other)
+    ->(*args, &block) { call(other.call(*args, &block)) }
+  end
+
+  def >>(other)
+    ->(*args, &block) { other.call(call(*args, &block)) }
+  end
 end
diff --git a/mrbgems/mruby-method/src/method.c b/mrbgems/mruby-method/src/method.c
index 600567cac..b5050368d 100644
--- a/mrbgems/mruby-method/src/method.c
+++ b/mrbgems/mruby-method/src/method.c
@@ -29,8 +29,7 @@ unbound_method_bind(mrb_state *mrb, mrb_value self)
         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)));
+          mrb_raisef(mrb, E_TYPE_ERROR, "bind argument must be an instance of %v", owner);
         }
   }
   me = method_object_alloc(mrb, mrb_class_get(mrb, "Method"));
@@ -212,19 +211,8 @@ 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;
+  mrb_int arity = mrb_nil_p(proc) ? -1 : mrb_proc_arity(mrb_proc_ptr(proc));
+  return mrb_fixnum_value(arity);
 }
 
 static mrb_value
@@ -281,16 +269,16 @@ method_to_s(mrb_state *mrb, mrb_value 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_str(mrb, str, mrb_str_to_str(mrb, owner));
     mrb_str_cat_lit(mrb, str, "#");
-    mrb_str_cat_str(mrb, str, mrb_funcall(mrb, name, "to_s", 0));
+    mrb_str_cat_str(mrb, str, mrb_str_to_str(mrb, name));
   }
   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_str(mrb, str, mrb_str_to_str(mrb, owner));
     mrb_str_cat_lit(mrb, str, ")#");
-    mrb_str_cat_str(mrb, str, mrb_funcall(mrb, name, "to_s", 0));
+    mrb_str_cat_str(mrb, str, mrb_str_to_str(mrb, name));
   }
   mrb_str_cat_lit(mrb, str, ">");
   return str;
@@ -300,7 +288,6 @@ 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);
@@ -324,13 +311,7 @@ mrb_search_method_owner(mrb_state *mrb, struct RClass *c, mrb_value obj, mrb_sym
   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))
-  );
+  mrb_raisef(mrb, E_NAME_ERROR, "undefined method '%n' for class '%C'", name, c);
 }
 
 static mrb_value
diff --git a/mrbgems/mruby-method/test/method.rb b/mrbgems/mruby-method/test/method.rb
index 9fd6a558e..0b67d3e61 100644
--- a/mrbgems/mruby-method/test/method.rb
+++ b/mrbgems/mruby-method/test/method.rb
@@ -21,7 +21,7 @@ class Interpreter
   }
   def interpret(string)
     @ret = ""
-    string.each_char {|b| Dispatcher[b].bind(self).call }
+    string.split("").each {|b| Dispatcher[b].bind(self).call }
   end
 end
 
@@ -371,6 +371,25 @@ assert "Method#initialize_copy" do
   assert_equal(m1, m2)
 end
 
+assert "Method#<< and Method#>>" do
+  obj = Object.new
+  class << obj
+    def mul2(n); n * 2; end
+    def add3(n); n + 3; end
+  end
+
+  f = obj.method(:mul2)
+  g = obj.method(:add3)
+
+  m1 = f << g
+  assert_kind_of Proc, m1
+  assert_equal 16, m1.call(5)
+
+  m2 = f >> g
+  assert_kind_of Proc, m2
+  assert_equal 13, m2.call(5)
+end
+
 assert 'UnboundMethod#arity' do
   c = Class.new {
     def foo(a, b)