BUG #7709: psql \copy csv terminates with \. in quoted region

The following bug has been logged on the website:

Bug reference:      7709
Logged by:          Timothy Garnett
Email address:      tgarnett@panjiva.com
PostgreSQL version: 9.1.2
Operating system:   Ubuntu 10.04.4 LTS
Description:        =


psql \copy terminates at \. by itself in a line even if the format is csv
and the \. is inside a quoted region.  This means that some values can't be
round-tripped by psql \copy. Tested and the native postgresql COPY handles
this case correctly.

Ex:
=3D# CREATE TEMPORARY TABLE test_table AS (SELECT 1 AS id, '
\.
'::text AS data, 2 AS num_data);
=3D# \copy test_table to '/tmp/dummy.csv' csv
=3D# TRUNCATE TABLE test_table;
=3D# \copy test_table from '/tmp/dummy.csv' csv
ERROR:  unterminated CSV quoted field
CONTEXT:  COPY test_table, line 1: "1,"
"


(postgresql COPY can handle this case though:
=3D# COPY test_table TO '/tmp/TEST_DATA.csv' WITH (FORMAT CSV);
=3D# TRUNCATE TABLE test_table;
=3D# COPY test_table FROM '/tmp/TEST_DATA.csv' WITH (FORMAT CSV);
works fine)