MDEV-37397 Assertion `bitmap_is_set(&read_partitions, next->id)' failed in int partition_info::vers_set_hist_part(THD *)

after 633417308f (MDEV-37312) lookup_handler is locked with F_WRLCK,
because it may be used for deleting rows.

And lookup_handler is locked with F_WRLCK after prune_partitions(),
but the main handler is locked before, and might expects all
partitions to be in the read least, non-pruned.

Let's prepare the lookup handler before prune_partitions().

mysql-test/suite/period/r/long_unique.result

@@ -31,4 +31,10 @@ set transaction isolation level read committed;
 update t1 for portion of p from '1980-01-01' to '1980-01-02' set a = 1;
 ERROR 23000: Duplicate entry 'foo' for key 'f'
 drop table t1;
+#
+# MDEV-37397 Assertion `bitmap_is_set(&read_partitions, next->id)' failed in int partition_info::vers_set_hist_part(THD *)
+#
+create table t (f int,s date,e date,period for p (s,e),unique (f,p without overlaps)) with system versioning partition by system_time limit+1 (partition p history,partition pn current);
+delete from t;
+drop table t;
 # End of 10.6 tests

mysql-test/suite/period/t/long_unique.test

@@ -41,4 +41,11 @@ set transaction isolation level read committed;
 update t1 for portion of p from '1980-01-01' to '1980-01-02' set a = 1;
 drop table t1;
 
+--echo #
+--echo # MDEV-37397 Assertion `bitmap_is_set(&read_partitions, next->id)' failed in int partition_info::vers_set_hist_part(THD *)
+--echo #
+create table t (f int,s date,e date,period for p (s,e),unique (f,p without overlaps)) with system versioning partition by system_time limit+1 (partition p history,partition pn current);
+delete from t;
+drop table t;
+
 --echo # End of 10.6 tests

sql/sql_delete.cc

@@ -511,6 +511,9 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds,
     }
   }
 
+  if (table->versioned(VERS_TIMESTAMP) || (table_list->has_period()))
+    table->file->prepare_for_insert(1);
+
 #ifdef WITH_PARTITION_STORAGE_ENGINE
   if (prune_partitions(thd, table, conds))
   {
@@ -813,8 +816,6 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds,
           && !table->versioned()
           && table->file->has_transactions();
 
-  if (table->versioned(VERS_TIMESTAMP) || (table_list->has_period()))
-    table->file->prepare_for_insert(1);
   DBUG_ASSERT(table->file->inited != handler::NONE);
 
   THD_STAGE_INFO(thd, stage_updating);

sql/sql_update.cc

@@ -559,6 +559,7 @@ int mysql_update(THD *thd,
 
   // Don't count on usage of 'only index' when calculating which key to use
   table->covering_keys.clear_all();
+  table->file->prepare_for_insert(1);
 
 #ifdef WITH_PARTITION_STORAGE_ENGINE
   if (prune_partitions(thd, table, conds))
@@ -1021,7 +1022,6 @@ update_begin:
   can_compare_record= records_are_comparable(table);
   explain->tracker.on_scan_init();
 
-  table->file->prepare_for_insert(1);
   DBUG_ASSERT(table->file->inited != handler::NONE);
 
   THD_STAGE_INFO(thd, stage_updating);