bug #24502 (reorganize partition closes connection)

when REORGANIZE creates new partition, no_subparts for that partition
isn't set right (call handler::set_partitions_defaults always returns 1)
Normally the number of subpartitions should be inherited from the
table.

mysql-test/r/partition.result

@@ -1128,4 +1128,14 @@ a
 18446744073709551613
 18446744073709551614
 drop table t1;
+CREATE TABLE t1 (
+num int(11) NOT NULL, cs int(11) NOT NULL)
+PARTITION BY RANGE (num) SUBPARTITION BY HASH (
+cs) SUBPARTITIONS 2 (PARTITION p_X VALUES LESS THAN MAXVALUE);
+ALTER TABLE t1 
+REORGANIZE PARTITION p_X INTO ( 
+PARTITION p_100 VALUES LESS THAN (100), 
+PARTITION p_X VALUES LESS THAN MAXVALUE 
+);
+drop table t1;
 End of 5.1 tests

mysql-test/t/partition.test

@@ -1354,4 +1354,20 @@ delete from t1 where a = 18446744073709551615;
 select * from t1;
 drop table t1;
 
+#
+# Bug 24502 reorganize partition closes connection
+#
+CREATE TABLE t1 (
+  num int(11) NOT NULL, cs int(11) NOT NULL)
+PARTITION BY RANGE (num) SUBPARTITION BY HASH (
+cs) SUBPARTITIONS 2 (PARTITION p_X VALUES LESS THAN MAXVALUE);
+
+ALTER TABLE t1 
+REORGANIZE PARTITION p_X INTO ( 
+    PARTITION p_100 VALUES LESS THAN (100), 
+    PARTITION p_X VALUES LESS THAN MAXVALUE 
+    );
+
+drop table t1;
+
 --echo End of 5.1 tests

sql/sql_partition.cc

@@ -4739,6 +4739,7 @@ state of p1.
       }
       alt_part_info->part_type= tab_part_info->part_type;
       alt_part_info->subpart_type= tab_part_info->subpart_type;
+      alt_part_info->no_subparts= tab_part_info->no_subparts;
       DBUG_ASSERT(!alt_part_info->use_default_partitions);
       if (alt_part_info->set_up_defaults_for_partitioning(table->file,
                                                           ULL(0),