From: Tom Lane <tgl@sss.pgh.pa.us>
To: pgsql-committers@lists.postgresql.org
Subject: pgsql: Fix plpgsql's handling of -- comments following expressions.
Date: Wed, 10 Apr 2024 19:46:16 +0000
Message-ID: <E1rudtg-001Ufy-4l@gemulon.postgresql.org> (raw)
Fix plpgsql's handling of -- comments following expressions.
Up to now, read_sql_construct() has collected all the source text from
the statement or expression's initial token up to the character just
before the "until" token. It normally tries to strip trailing
whitespace from that, largely for neatness. If there was a "-- text"
comment after the expression, this resulted in removing the newline
that terminates the comment, which creates a hazard if we try to paste
the collected text into a larger SQL construct without inserting a
newline after it. In particular this caused our handling of CASE
constructs to fail if there's a comment after a WHEN expression.
Commit 4adead1d2 noticed a similar problem with cursor arguments,
and worked around it through the rather crude hack of suppressing
the whitespace-trimming behavior for those. Rather than do that
and leave the hazard open for future hackers to trip over, let's
fix it properly. pl_scanner.c already has enough infrastructure
to report the end location of the expression's last token, so
we can copy up to that location and never collect any trailing
whitespace or comment to begin with.
Erik Wienhold and Tom Lane, per report from Michal Bartak.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAAVzF_FjRoi8fOVuLCZhQJx6HATQ7MKm=aFOHWZODFnLmjX-xA@mail.gmail.com
Branch
------
REL_12_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/5e9d8bed0094b146d64013d417c51eb0f69aeafd
Modified Files
--------------
src/pl/plpgsql/src/expected/plpgsql_control.out | 17 ++++++++++
src/pl/plpgsql/src/pl_gram.y | 43 +++++++++++--------------
src/pl/plpgsql/src/pl_scanner.c | 17 ++++++++++
src/pl/plpgsql/src/plpgsql.h | 1 +
src/pl/plpgsql/src/sql/plpgsql_control.sql | 14 ++++++++
src/test/regress/expected/plpgsql.out | 8 ++---
src/test/regress/sql/plpgsql.sql | 8 ++---
7 files changed, 74 insertions(+), 34 deletions(-)
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-committers@postgresql.org
Cc: tgl@sss.pgh.pa.us, pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Fix plpgsql's handling of -- comments following expressions.
In-Reply-To: <E1rudtg-001Ufy-4l@gemulon.postgresql.org>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox