psql doesn't count lines correctly in pg_dump scripts

It appears that psql does not count COPY data lines while counting
lines in an input script.  This makes its reported line numbers
rather useless in a script such as those produced by pg_dump.

For example,

COPY tbl1 FROM stdin;
... some data lines here...
\.

COPY tbl2 FROM stdin;
... put some erroneous data here that will be rejected by input conversion...
\.

then do "\i scriptfile".

The error report will mention the second copy's line number, less the
number of lines occupied by the first table's data.

            regards, tom lane