MDEV-15308 Assertion `ha_alter_info->alter_info->drop_list.elementsbb-10.0-monty

Problem was that handle_if_exists_options() didn't correct
alter_info->flags when things was removed from the list.

2 files changed, 93 insertions, 0 deletions

diff --git a/mysql-test/r/alter_table.result b/mysql-test/r/alter_table.result
index e32037c4be9..bb78df907ad 100644
--- a/mysql-test/r/alter_table.result
+++ b/mysql-test/r/alter_table.result
@@ -2164,3 +2164,64 @@ t1	CREATE TABLE `t1` (
   `b` int(11) DEFAULT NULL
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8
 DROP TABLE t1;
+#
+#
+# MDEV-15308
+# Assertion `ha_alter_info->alter_info->drop_list.elements > 0' failed
+# in ha_innodb::prepare_inplace_alter_table
+#
+CREATE TABLE t1 (a INT, b INT) ENGINE=InnoDB;
+ALTER TABLE t1 DROP FOREIGN KEY IF EXISTS fk, DROP COLUMN b;
+Warnings:
+Note	1091	Can't DROP 'fk'; check that column/key exists
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, b INT) ENGINE=InnoDB;
+ALTER TABLE t1 DROP INDEX IF EXISTS fk, DROP COLUMN b;
+Warnings:
+Note	1091	Can't DROP 'fk'; check that column/key exists
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, b INT, c INT, KEY(c)) ENGINE=InnoDB;
+ALTER TABLE t1 DROP FOREIGN KEY IF EXISTS fk, DROP COLUMN c;
+Warnings:
+Note	1091	Can't DROP 'fk'; check that column/key exists
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL,
+  `b` int(11) DEFAULT NULL
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, b INT, c INT, KEY c1(c)) ENGINE=InnoDB;
+ALTER TABLE t1 DROP FOREIGN KEY IF EXISTS fk, DROP INDEX c1;
+Warnings:
+Note	1091	Can't DROP 'fk'; check that column/key exists
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL,
+  `b` int(11) DEFAULT NULL,
+  `c` int(11) DEFAULT NULL
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+DROP TABLE t1;
+CREATE TABLE t1 (a INT, b INT) ENGINE=InnoDB;
+ALTER TABLE t1 DROP INDEX IF EXISTS fk, DROP COLUMN IF EXISTS c;
+Warnings:
+Note	1091	Can't DROP 'fk'; check that column/key exists
+Note	1091	Can't DROP 'c'; check that column/key exists
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL,
+  `b` int(11) DEFAULT NULL
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+DROP TABLE t1;
diff --git a/mysql-test/t/alter_table.test b/mysql-test/t/alter_table.test
index 8fcc7d044e5..585a272de9b 100644
--- a/mysql-test/t/alter_table.test
+++ b/mysql-test/t/alter_table.test
@@ -1809,3 +1809,35 @@ SHOW CREATE TABLE t1;
 ALTER TABLE t1 CONVERT TO CHARACTER SET utf8;
 SHOW CREATE TABLE t1;
 DROP TABLE t1;
+
+--echo #
+--echo #
+--echo # MDEV-15308
+--echo # Assertion `ha_alter_info->alter_info->drop_list.elements > 0' failed
+--echo # in ha_innodb::prepare_inplace_alter_table
+--echo #
+
+CREATE TABLE t1 (a INT, b INT) ENGINE=InnoDB;
+ALTER TABLE t1 DROP FOREIGN KEY IF EXISTS fk, DROP COLUMN b;
+SHOW CREATE TABLE t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT, b INT) ENGINE=InnoDB;
+ALTER TABLE t1 DROP INDEX IF EXISTS fk, DROP COLUMN b;
+SHOW CREATE TABLE t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT, b INT, c INT, KEY(c)) ENGINE=InnoDB;
+ALTER TABLE t1 DROP FOREIGN KEY IF EXISTS fk, DROP COLUMN c;
+SHOW CREATE TABLE t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT, b INT, c INT, KEY c1(c)) ENGINE=InnoDB;
+ALTER TABLE t1 DROP FOREIGN KEY IF EXISTS fk, DROP INDEX c1;
+SHOW CREATE TABLE t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INT, b INT) ENGINE=InnoDB;
+ALTER TABLE t1 DROP INDEX IF EXISTS fk, DROP COLUMN IF EXISTS c;
+SHOW CREATE TABLE t1;
+DROP TABLE t1;