Plugin aggregate DISTINCT replay order depends on the argument data type

INSTALL SONAME 'func_test';

CREATE TABLE t (i INT, vc VARCHAR(16), tx TEXT);

INSERT INTO t VALUES  (9,'zzz','zzz'), (5,'mmm','mmm'), (9,'zzz','zzz'), (1,'aaa','aaa'), (5,'mmm','mmm');

SELECT test_plugin_first(i),  test_plugin_first(vc),  test_plugin_first(tx)  FROM t;

SELECT test_plugin_first(DISTINCT i), test_plugin_first(DISTINCT vc), test_plugin_first(DISTINCT tx) FROM t;

column type              no DISTINCT    with DISTINCT  

INT         (tree path)       9              1            

VARCHAR(16) (tree path)     zzz            aaa            

TEXT        (blob replay)   zzz            zzz            

test_plugin_first(DISTINCT vc) = 'aaa'

test_plugin_first(DISTINCT tx) = 'zzz'

13.2.0-dbg>INSTALL SONAME 'func_test';

Query OK, 0 rows affected (0.003 sec)

13.2.0-dbg>CREATE TABLE t (i INT, vc VARCHAR(16), tx TEXT);

Query OK, 0 rows affected (0.010 sec)

13.2.0-dbg>INSERT INTO t VALUES  (9,'zzz','zzz'), (5,'mmm','mmm'), (9,'zzz','zzz'), (1,'aaa','aaa'), (5,'mmm','mmm');

Query OK, 5 rows affected (0.002 sec)

Records: 5  Duplicates: 0  Warnings: 0

13.2.0-dbg>

13.2.0-dbg>SELECT test_plugin_first(i),  test_plugin_first(vc),  test_plugin_first(tx)  FROM t;

+----------------------+-----------------------+-----------------------+

| test_plugin_first(i) | test_plugin_first(vc) | test_plugin_first(tx) |

+----------------------+-----------------------+-----------------------+

|                    9 | zzz                   | zzz                   |

+----------------------+-----------------------+-----------------------+

1 row in set (0.000 sec)

13.2.0-dbg>SELECT test_plugin_first(DISTINCT i), test_plugin_first(DISTINCT vc), test_plugin_first(DISTINCT tx) FROM t;

+-------------------------------+--------------------------------+--------------------------------+

| test_plugin_first(DISTINCT i) | test_plugin_first(DISTINCT vc) | test_plugin_first(DISTINCT tx) |

+-------------------------------+--------------------------------+--------------------------------+

|                             1 | aaa                            | zzz                            |

+-------------------------------+--------------------------------+--------------------------------+

1 row in set (0.002 sec)

13.2.0-dbg>