Ruby » Ruby master

sprintf.c: nil value is valid

• sprintf.c (rb_str_format): look up the key, then get default
  value and raise KeyError if the returned value is nil.
  [ruby-dev:49338] [Ruby trunk - Bug #11677]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52537 b2dd03c8-39d4-4d8f-98ff-823fe69b080e