merge revision(s) 56111: [Backport #12738]

	* array.c (flatten): use rb_obj_class instead of rb_class_of
	  because rb_class_of may return a singleton class.
	  [ruby-dev:49781] [Bug #12738]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@56233 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

4 files changed, 26 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index cd9d2432ab..52dd24a6f5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Sun Sep 25 15:09:04 2016  Kazuki Tsujimoto  <kazuki@callcc.net>
+
+	* array.c (flatten): use rb_obj_class instead of rb_class_of
+	  because rb_class_of may return a singleton class.
+	  [ruby-dev:49781] [Bug #12738]
+
 Sun Sep 25 15:07:19 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* man/irb.1: remove useless -width option.
diff --git a/array.c b/array.c
index dd14837b76..729de9c081 100644
--- a/array.c
+++ b/array.c
@@ -4461,7 +4461,7 @@ flatten(VALUE ary, int level, int *modified)
 
     st_free_table(memo);
 
-    RBASIC_SET_CLASS(result, rb_class_of(ary));
+    RBASIC_SET_CLASS(result, rb_obj_class(ary));
     return result;
 }
 
diff --git a/test/ruby/test_array.rb b/test/ruby/test_array.rb
index eacc0b007b..f27b8a5724 100644
--- a/test/ruby/test_array.rb
+++ b/test/ruby/test_array.rb
@@ -805,6 +805,15 @@ class TestArray < Test::Unit::TestCase
     assert_nothing_raised(RuntimeError, bug10748) {a.flatten(1)}
   end
 
+  def test_flattern_singleton_class
+    bug12738 = '[ruby-dev:49781] [Bug #12738]'
+    a = [[0]]
+    class << a
+      def m; end
+    end
+    assert_raise(NoMethodError, bug12738) { a.flatten.m }
+  end
+
   def test_flatten!
     a1 = @cls[ 1, 2, 3]
     a2 = @cls[ 5, 6 ]
@@ -842,6 +851,15 @@ class TestArray < Test::Unit::TestCase
     assert_nothing_raised(RuntimeError, bug10748) {a.flatten!(1)}
   end
 
+  def test_flattern_singleton_class!
+    bug12738 = '[ruby-dev:49781] [Bug #12738]'
+    a = [[0]]
+    class << a
+      def m; end
+    end
+    assert_nothing_raised(NameError, bug12738) { a.flatten!.m }
+  end
+
   def test_flatten_with_callcc
     need_continuation
     o = Object.new
diff --git a/version.h b/version.h
index c84b487403..5387687598 100644
--- a/version.h
+++ b/version.h
@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.3.2"
 #define RUBY_RELEASE_DATE "2016-09-25"
-#define RUBY_PATCHLEVEL 183
+#define RUBY_PATCHLEVEL 184
 
 #define RUBY_RELEASE_YEAR 2016
 #define RUBY_RELEASE_MONTH 9