Table partionning : INSERT with inconsistent return ligne inserted.

Hi,

I use PostgreSQL 9.6 (9.6.3) with table partitioning, when I use INSERT order psql, it does not show the number of lines inserted.
I do not see any information in the version notes from the PostgreSQL documentation, even with the 9.6.5 update, is it some bug ?

Here is a short test case :

--
-- table
--

CREATE TABLE t1_part

( id BIGINT ,
libelle VARCHAR(30 )
)
WITH ( FILLFACTOR = 70 )
TABLESPACE data_1
;

--
-- partitions : 2.
--
CREATE TABLE t1_part_01
( CHECK ( id >= 1 AND id <= 1000 )
)
INHERITS ( t1_part ) ;

CREATE TABLE t1_part_02
( CHECK ( id > 1000 AND id <= 22000000 )
)
INHERITS ( t1_part ) ;

--
-- function of partitionning
--

CREATE FUNCTION t1_part_test_trigger()
RETURNS TRIGGER AS $$
BEGIN
IF NEW.id >= 1 AND NEW.id <= 1000 THEN
INSERT INTO t1_part_01 VALUES (NEW.*);
ELSIF NEW.id > 1000 AND NEW.id <= 22000000 THEN
INSERT INTO t1_part_02 VALUES (NEW.*);
END IF ;
RETURN NULL;
END;
$$
LANGUAGE plpgsql;

--
-- trigger
--

CREATE TRIGGER insert_t1_part
BEFORE INSERT ON t1_part
FOR EACH ROW EXECUTE PROCEDURE t1_part_test_trigger();

--
-- Insert
--

hba=> insert into t1_part values (3000001, '3000001' ) ;
INSERT 0 0 -- should be "INSERT 0 1"

hba=> select * from t1_part ;
id | libelle
---------+----------
3000001 | 3000001
(1 row) -- proof of successful insert.

Thanks by advance.
Didier Sterbecq