Fix pp when passed a empty ruby2_keywords-flagged hash as array element

This causes problems because the hash is passed to a block not
accepting keywords.  Because the hash is empty and keyword flagged,
it is removed before calling the block.  This doesn't cause an
ArgumentError because it is a block and not a lambda.  Just like
any other block not passed required arguments, arguments not
passed are set to nil.

Issues like this are a strong reason not to have ruby2_keywords
by default.

Fixes [Bug #16519]

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/pp.rb b/lib/pp.rb
index 81a9a1629c..dede0d1517 100644
--- a/lib/pp.rb
+++ b/lib/pp.rb
@@ -223,7 +223,7 @@ class PP < PrettyPrint
         else
           sep.call
         end
-        yield(*v)
+        yield(*v, **{})
       }
     end