Also added test for charsh bug with Struct.new without parameters.

test/t/struct.rb

@@ -16,11 +16,11 @@ if Object.const_defined?(:Struct)
       c.members == [:m1,:m2]
   end
 
-  # Crash bug withStruc.new and no params, should make empty struct?
-  # assert('Struct.new', '15.2.18.3.1') do
-  #   c = Struct.new()
-  #   c.superclass == Struct   
-  # end
+  # Check crash bug with Struc.new and no params.
+  assert('Struct.new', '15.2.18.3.1') do
+     c = Struct.new()
+     c.superclass == Struct and c.members == []
+  end
 
   assert('Struct#==', '15.2.18.4.1') do
     c = Struct.new(:m1, :m2)