merge revision(s) 51651,51655: [Backport #11451]

	* vm_insnhelper.c (vm_invoke_block): we should not expect ci->argc is
	  stable after invoking a block. [Bug #11451]

	* test/ruby/test_yield.rb: add a test. This test script is given by
	  Alex Dowad.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_2@52717 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 24 insertions, 0 deletions

diff --git a/test/ruby/test_yield.rb b/test/ruby/test_yield.rb
index 82378d48b4..f12ba2c73d 100644
--- a/test/ruby/test_yield.rb
+++ b/test/ruby/test_yield.rb
@@ -390,4 +390,28 @@ class TestRubyYieldGen < Test::Unit::TestCase
     end
     assert_equal [m, nil], y.s(m){|a,b|[a,b]}
   end
+
+  def test_block_cached_argc
+    # [Bug #11451]
+    assert_separately([], <<-"end;")
+      class Yielder
+        def each
+          yield :x, :y, :z
+        end
+      end
+      class Getter1
+        include Enumerable
+        def each(&block)
+          Yielder.new.each(&block)
+        end
+      end
+      class Getter2
+        include Enumerable
+        def each
+          Yielder.new.each { |a, b, c, d| yield(a) }
+        end
+      end
+      Getter1.new.map{Getter2.new.each{|x|}}
+    end;
+  end
 end