fails:String#unpack with format 'E' ignores whitespace in the format string
fails:String#unpack with format 'E' calls #to_str to coerce the directives string
fails:String#unpack with format 'E' adds nil for each element requested beyond the end of the String
fails:String#unpack with format 'e' ignores whitespace in the format string
fails:String#unpack with format 'e' calls #to_str to coerce the directives string
fails:String#unpack with format 'e' adds nil for each element requested beyond the end of the String
