Parsed test spec with 2 sessions

starting permutation: s0_begin s0_begin_sub0 s0_log_assignment s0_sub_get_base_snap s1_produce_new_snap s0_insert s0_end_sub0 s0_commit s0_get_changes
step s0_begin: BEGIN;
step s0_begin_sub0: SAVEPOINT s0;
step s0_log_assignment: SELECT pg_current_xact_id() IS NULL;
?column?
--------
f       
(1 row)

step s0_sub_get_base_snap: INSERT INTO dummy VALUES (0);
step s1_produce_new_snap: ALTER TABLE harvest ADD COLUMN mangos int;
step s0_insert: INSERT INTO harvest VALUES (1, 2, 3);
step s0_end_sub0: RELEASE SAVEPOINT s0;
step s0_commit: COMMIT;
step s0_get_changes: SELECT data FROM pg_logical_slot_get_changes('isolation_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
data                                                                              
----------------------------------------------------------------------------------
BEGIN                                                                             
table public.dummy: INSERT: i[integer]:0                                          
table public.harvest: INSERT: apples[integer]:1 pears[integer]:2 mangos[integer]:3
COMMIT                                                                            
(4 rows)

?column?
--------
stop    
(1 row)


starting permutation: s0_begin s0_begin_sub0 s0_log_assignment s0_begin_sub1 s0_sub_get_base_snap s1_produce_new_snap s0_insert s0_end_sub1 s0_end_sub0 s0_commit s0_get_changes
step s0_begin: BEGIN;
step s0_begin_sub0: SAVEPOINT s0;
step s0_log_assignment: SELECT pg_current_xact_id() IS NULL;
?column?
--------
f       
(1 row)

step s0_begin_sub1: SAVEPOINT s1;
step s0_sub_get_base_snap: INSERT INTO dummy VALUES (0);
step s1_produce_new_snap: ALTER TABLE harvest ADD COLUMN mangos int;
step s0_insert: INSERT INTO harvest VALUES (1, 2, 3);
step s0_end_sub1: RELEASE SAVEPOINT s1;
step s0_end_sub0: RELEASE SAVEPOINT s0;
step s0_commit: COMMIT;
step s0_get_changes: SELECT data FROM pg_logical_slot_get_changes('isolation_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
data                                                                              
----------------------------------------------------------------------------------
BEGIN                                                                             
table public.dummy: INSERT: i[integer]:0                                          
table public.harvest: INSERT: apples[integer]:1 pears[integer]:2 mangos[integer]:3
COMMIT                                                                            
(4 rows)

?column?
--------
stop    
(1 row)