Surprising behaviour of \set AUTOCOMMIT ON

If  \set AUTOCOMMIT ON is issued after \set AUTOCOMMIT OFF the commands which follow after AUTOCOMMIT is set ON are not committed until an explicit COMMIT is issued.
Its can be surprising to the user to not see results of the commands fired after AUTOCOMMIT is set to ON.

bash-4.2$ psql -d postgres -U rahila
psql (9.6beta3)
Type "help" for help.

postgres=# \set AUTOCOMMIT OFF
postgres=# create table test1(i int);
CREATE TABLE
postgres=# \set AUTOCOMMIT ON
postgres=# create table test2(j int);
CREATE TABLE
postgres=# \c postgres rahila
You are now connected to database "postgres" as user "rahila".
postgres=# \dt;
No relations found.

The ongoing transaction is left running when there is this change in mode from AUTOCOMMIT OFF to AUTOCOMMIT ON. 
This happens because \set AUTOCOMMIT ON is fired within a transaction block started when first command after \set AUTOCOMMIT OFF is executed. Hence it requires an explicit COMMIT to be effective.

Should changing the value from OFF to ON automatically either commit or rollback transaction in progress?
FWIW, running  set autocommit through ecpg commits the ongoing transaction when autocommit is set to ON from OFF. Should such behaviour be implemented for \set AUTOCOMMIT ON as well?

Thank you,
Rahila Syed