Add first test case for Class#new and prepare further feature tests for it

test/t/class.rb

@@ -5,6 +5,36 @@ assert('Class', '15.2.3') do
   Class.class == Class
 end
 
+assert('Class#new', '15.2.3.3.3') do
+  # at the moment no exception on singleton class
+  #e1 = nil
+  #begin
+  #  class1 = e1.singleton_class.new
+  #rescue => e1
+  #  e2 = e1
+  #end
+
+  class TestClass
+    def initialize args, &block
+      @result = if not args.nil? and block.nil?
+        # only arguments
+        :only_args
+      elsif not args.nil? and not block.nil?
+        # args and block is given
+        :args_and_block
+      else
+        # this should never happen
+        :broken
+      end
+    end
+
+    def result; @result; end
+  end
+
+  TestClass.new(:arg).result == :only_args
+    # with block doesn't work yet
+end
+
 # Not ISO specified
 
 assert('Class 1') do