pg_dump --if-exists --clean when drop index that is partition of a partitioned index

hi.

CREATE TABLE tp(c int, a int, b int) PARTITION BY RANGE (b);
CREATE TABLE tp_1(c int, a int, b int);
ALTER TABLE tp ATTACH PARTITION tp_1 FOR VALUES FROM (0) TO (1);
CREATE INDEX t_a_idx ON tp_1(a);
CREATE INDEX tp_a_idx ON tp(a);

pg_dump --schema=public --if-exists --clean --no-statistics
--no-owner --no-data --table-and-children=tp > 1.sql
pg_dump output file 1.sql excerpts:
----
DROP INDEX IF EXISTS public.t_a_idx;
DROP INDEX IF EXISTS public.tp_a_idx;
DROP TABLE IF EXISTS public.tp_1;
DROP TABLE IF EXISTS public.tp;
----
if you execute the
DROP INDEX IF EXISTS public.t_a_idx;

ERROR: cannot drop index t_a_idx because index tp_a_idx requires it
HINT: You can drop index tp_a_idx instead.

Is this pg_dump output what we expected?

SELECT * FROM pg_partition_tree('tp_a_idx');
relid | parentrelid | isleaf | level
----------+-------------+--------+-------
tp_a_idx | | f | 0
t_a_idx | tp_a_idx | t | 1
(2 rows)