Merge pull request #2221 from yui-knk/add-exception-test

Add exception test

test/t/exception.rb

@@ -341,7 +341,7 @@ assert('Exception 19') do
 end
 
 assert('Exception#inspect without message') do
-  Exception.new.inspect
+  assert_equal "Exception: Exception", Exception.new.inspect
 end
 
 assert('Exception#backtrace') do