# Check replication of one statement assuming that the engine on the
# slave is a blackhole engine.

# Input:
# $statement    Statement to evaluate, it is assumed to change t1

# 1. Evaluate statement on master, it is assumed to change t1
# 2. Wait for statement to be processed on slave
# 3. SELECT from table t1 to see what was written
# 4. Compare position on slave before executing statement and after
#    executing statement. If difference is >0, then something was
#    written to the binary log on the slave.

connection slave;
let $before = query_get_value("SHOW MASTER STATUS", Position, 1);

--echo [on master]
connection master;
eval $statement;

--echo [on slave]
sync_slave_with_master;
--echo # Expect 0
SELECT COUNT(*) FROM t1;
let $after = query_get_value("SHOW MASTER STATUS", Position, 1);
let $something_written = `select $after - $before != 0`;
if ($something_written) {
  --echo >>> Something was written to binary log <<<
}
if (!$something_written) {
  --echo >>> Nothing was written to binary log <<<
}