Parsed test spec with 2 sessions

starting permutation: s0_begin s0_update s1_begin s1_tuplock s0_commit s1_commit
step s0_begin: BEGIN ISOLATION LEVEL READ COMMITTED;
step s0_update: UPDATE a SET i = i + 1;
step s1_begin: BEGIN ISOLATION LEVEL READ COMMITTED;
step s1_tuplock: 
    -- Verify if the sub-select has a foreign-join plan
    EXPLAIN (VERBOSE, COSTS OFF)
    SELECT a.i,
        (SELECT 1 FROM fb, fc WHERE a.i = fb.i AND fb.i = fc.i)
    FROM a FOR UPDATE;
    SELECT a.i,
        (SELECT 1 FROM fb, fc WHERE a.i = fb.i AND fb.i = fc.i)
    FROM a FOR UPDATE;
 <waiting ...>
step s0_commit: COMMIT;
step s1_tuplock: <... completed>
QUERY PLAN                                                                                                                              
----------------------------------------------------------------------------------------------------------------------------------------
LockRows                                                                                                                                
  Output: a.i, ((SubPlan 1)), a.ctid                                                                                                    
  ->  Seq Scan on public.a                                                                                                              
        Output: a.i, (SubPlan 1), a.ctid                                                                                                
        SubPlan 1                                                                                                                       
          ->  Foreign Scan                                                                                                              
                Output: 1                                                                                                               
                Relations: (public.fb) INNER JOIN (public.fc)                                                                           
                Remote SQL: SELECT NULL FROM (public.b r1 INNER JOIN public.c r2 ON (((r2.i = $1::integer)) AND ((r1.i = $1::integer))))
(9 rows)

i|?column?
-+--------
2|        
(1 row)

step s1_commit: COMMIT;