added enum tests

localtests/enum/create.sql

@@ -0,0 +1,27 @@
+drop table if exists gh_ost_test;
+create table gh_ost_test (
+  id int auto_increment,
+  i int not null,
+  e enum('red', 'green', 'blue', 'orange') null default null collate 'utf8_bin',
+  primary key(id)
+) auto_increment=1;
+
+drop event if exists gh_ost_test;
+delimiter ;;
+create event gh_ost_test
+  on schedule every 1 second
+  starts current_timestamp
+  ends current_timestamp + interval 60 second
+  on completion not preserve
+  enable
+  do
+begin
+  insert into gh_ost_test values (null, 11, 'red');
+  insert into gh_ost_test values (null, 13, 'green');
+  insert into gh_ost_test values (null, 17, 'blue');
+  set @last_insert_id := last_insert_id();
+  update gh_ost_test set e='orange' where id = @last_insert_id;
+  insert into gh_ost_test values (null, 23, null);
+  set @last_insert_id := last_insert_id();
+  update gh_ost_test set i=i+1, e=null where id = @last_insert_id;
+end ;;

localtests/enum/extra_args

@@ -0,0 +1 @@
+--alter="change e e enum('red', 'green', 'blue', 'orange', 'yellow') null default null collate 'utf8_bin'"