Re: pgsql: psql: add an optional execution-count limit to \watch.

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Aleksander Alekseev <aleksander@timescale.com>
Cc: pgsql-committers@lists.postgresql.org, Alexander Korotkov <aekorotkov@gmail.com>, Andrew Dunstan <andrew@dunslane.net>
Date: 2023-04-10T15:09:41Z
Lists: pgsql-hackers

Attachments

Aleksander Alekseev <aleksander@timescale.com> writes:
>> Hmm, so psql is honoring the LC_NUMERIC setting in that environment,
>> but perl isn't.  For me, it appears that adding 'use locale;' to
>> the test script will fix it ... can you confirm if it's OK for you?

> Right, src/bin/psql/t/001_basic.pl has "use locale;" since cd82e5c7
> and it fails nevertheless.
> ...
> So it looks like what happens is LC_ALL overwrites LC_NUMERIC for perl
> but not for psql.

Oh, right, there already is one :-(.  After some more research,
I believe I see the problem: Utils.pm does

BEGIN
{
	# Set to untranslated messages, to be able to compare program output
	# with expected strings.
	delete $ENV{LANGUAGE};
	delete $ENV{LC_ALL};
	$ENV{LC_MESSAGES} = 'C';

Normally, with your settings, LC_ALL=en_US.UTF-8 would dominate
everything.  After removing that from the environment, the child
psql process will honor LC_NUMERIC=ru_RU.UTF-8 and expect \watch's
argument to be "0,01".  However, I bet that perl has already made
its decisions about what its internal locale is, so it still thinks
it should print "0.01".

I am betting that we need to make Utils.pm do

	setlocale(LC_ALL, "");

after the above-quoted bit, else it isn't doing what it is supposed to
if the calling script has already done "use locale;", as indeed
psql/t/001_basic.pl (and a small number of other places) do.

The attached makes check-world pass for me under these conflicting
environment settings, but it's kind of a scary change.  Thoughts?

			regards, tom lane

Commits

  1. Fix Utils.pm's locale-munging so that Perl itself is also affected.

  2. Fix locale-dependent test case.

  3. psql: add an optional execution-count limit to \watch.