test case for low priority updates race bug

not yet fixed


mysql-test/r/lock.result:
  updated result
mysql-test/t/lock.test:
  test case for low prior updates bug

mysql-test/r/lock.result

@@ -4,3 +4,5 @@ Table	Op	Msg_type	Msg_text
 test.t1	check	status	OK
 Table	Op	Msg_type	Msg_text
 test.t2	check	error	Table 't2' was not locked with LOCK TABLES
+n
+1

mysql-test/t/lock.test

@@ -53,3 +53,25 @@ lock tables t1 write;
 check table t2;
 unlock tables;
 drop table t1,t2;
+
+#test to see if select will get the lock ahead of low priority update
+connect (locker,localhost,root,,);
+connect (reader,localhost,root,,);
+connect (writer,localhost,root,,);
+
+connection locker;
+create table t1(n int);
+insert into t1 values (1);
+lock tables t1 write;
+connection writer;
+send update low_priority t1 set n = 4;
+connection reader;
+send select n from t1;
+connection locker;
+unlock tables;
+connection writer;
+reap;
+connection reader;
+reap;
+drop table t1;
+