Login into PostgreSQL without password

Hi,

I have created a role using below sql, then I disconnected & try to login
into postgres db with newly created user "test_role", It prompt for
password and I pressed Enter key because I did not provided any password
when I created role so it throw me an error as below *Error: fe_sendauth:
no password supplied.*

Can someone please explain this behaviour of postgreSQL database, where I'm
not allowed to login without password even if I do not have password set
for "test_role" user?

The work around is I had to manually edit pg_hba conf and change
authentication method to trust for this user so that i can login without
password.

And If that's how postgreSQL authentication works, then can we add a
mechanism to disallow user to create role without password if running with
md5 authentication mode?

*SQL Query used to create role:*

CREATE USER test_role WITH
LOGIN
SUPERUSER
CREATEDB
CREATEROLE
INHERIT
REPLICATION
CONNECTION LIMIT -1;

--
Regards,
Murtuza Zabuawala
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company