BUG #14916: psql \r is invalid in PostgreSQL 10

The following bug has been logged on the website:

Bug reference: 14916
Logged by: Yunhe Xu
Email address: xyh(at)nvn(dot)xyz
PostgreSQL version: 10.1
Operating system: Red Hat Enterprise Linux Server release 6.7
Description:

Hello,
In PostgreSQL 10.0 and 10.1 .
psql \r is invalid.

postgres=# select count(*) from abc;
count
-------
0
(1 row)

postgres=# \r
Query buffer reset (cleared).
postgres=# \p
select count(*) from abc;

In 9.4.14,don't have this problem.
postgres=# select count(*) from abc;
count
-------
0
(1 row)

postgres=# \r
Query buffer reset (cleared).
postgres=# \p
Query buffer is empty.

Kind regards.
Yunhe