vm.c: check type of hash to merge

* vm.c (core_hash_merge): check the type of the target hash to
  merge.  [ruby-core:78536] [Bug #13015]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57024 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 20 insertions, 0 deletions

diff --git a/test/ruby/test_keyword.rb b/test/ruby/test_keyword.rb
index bcb93a6348..ad0bf63492 100644
--- a/test/ruby/test_keyword.rb
+++ b/test/ruby/test_keyword.rb
@@ -609,4 +609,24 @@ class TestKeywordArguments < Test::Unit::TestCase
       assert_equal({x: 1, y: 2, **h}, obj.foo)
     }
   end
+
+  def test_kwrest_overwritten
+    bug13015 = '[ruby-core:78536] [Bug #13015]'
+
+    klass = EnvUtil.labeled_class("Parent") do
+      def initialize(d:)
+      end
+    end
+
+    klass = EnvUtil.labeled_class("Child", klass) do
+      def initialize(d:, **h)
+        h = [2, 3]
+        super
+      end
+    end
+
+    assert_raise_with_message(TypeError, /expected Hash/, bug13015) do
+      klass.new(d: 4)
+    end
+  end
 end