From 2dd352d4b01648cac0354c754d9617b2e61f065d Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Thu, 12 Jun 2014 15:54:13 -0400
Subject: [PATCH] Add regression test to prevent future breakage of legacy
 query in libpq.

Memorialize the expected output of the query that libpq has been using for
many years to get the OIDs of large-object support functions.  Although
we really ought to change the way libpq does this, we must expect that
this query will remain in use in the field for the foreseeable future,
so until we're ready to break compatibility with old libpq versions
we'd better check the results stay the same.  See the recent lo_create()
fiasco.
---
 src/test/regress/expected/opr_sanity.out | 40 ++++++++++++++++++++++++
 src/test/regress/sql/opr_sanity.sql      | 24 ++++++++++++++
 2 files changed, 64 insertions(+)

diff --git a/src/test/regress/expected/opr_sanity.out b/src/test/regress/expected/opr_sanity.out
index 8c2443d6b3..c8d8ffd7ba 100644
--- a/src/test/regress/expected/opr_sanity.out
+++ b/src/test/regress/expected/opr_sanity.out
@@ -638,6 +638,46 @@ uuid_gt(uuid,uuid)
 uuid_ne(uuid,uuid)
 -- restore normal output mode
 \a\t
+-- List of functions used by libpq's fe-lobj.c
+--
+-- If the output of this query changes, you probably broke libpq.
+-- lo_initialize() assumes that there will be at most one match for
+-- each listed name.
+select proname, oid from pg_catalog.pg_proc
+where proname in (
+  'lo_open',
+  'lo_close',
+  'lo_creat',
+  'lo_create',
+  'lo_unlink',
+  'lo_lseek',
+  'lo_lseek64',
+  'lo_tell',
+  'lo_tell64',
+  'lo_truncate',
+  'lo_truncate64',
+  'loread',
+  'lowrite')
+and pronamespace = (select oid from pg_catalog.pg_namespace
+                    where nspname = 'pg_catalog')
+order by 1;
+    proname    | oid  
+---------------+------
+ lo_close      |  953
+ lo_creat      |  957
+ lo_create     |  715
+ lo_lseek      |  956
+ lo_lseek64    | 3170
+ lo_open       |  952
+ lo_tell       |  958
+ lo_tell64     | 3171
+ lo_truncate   | 1004
+ lo_truncate64 | 3172
+ lo_unlink     |  964
+ loread        |  954
+ lowrite       |  955
+(13 rows)
+
 -- **************** pg_cast ****************
 -- Catch bogus values in pg_cast columns (other than cases detected by
 -- oidjoins test).
diff --git a/src/test/regress/sql/opr_sanity.sql b/src/test/regress/sql/opr_sanity.sql
index de26af0d5a..213a66d4a3 100644
--- a/src/test/regress/sql/opr_sanity.sql
+++ b/src/test/regress/sql/opr_sanity.sql
@@ -317,6 +317,30 @@ ORDER BY 1;
 -- restore normal output mode
 \a\t
 
+-- List of functions used by libpq's fe-lobj.c
+--
+-- If the output of this query changes, you probably broke libpq.
+-- lo_initialize() assumes that there will be at most one match for
+-- each listed name.
+select proname, oid from pg_catalog.pg_proc
+where proname in (
+  'lo_open',
+  'lo_close',
+  'lo_creat',
+  'lo_create',
+  'lo_unlink',
+  'lo_lseek',
+  'lo_lseek64',
+  'lo_tell',
+  'lo_tell64',
+  'lo_truncate',
+  'lo_truncate64',
+  'loread',
+  'lowrite')
+and pronamespace = (select oid from pg_catalog.pg_namespace
+                    where nspname = 'pg_catalog')
+order by 1;
+
 
 -- **************** pg_cast ****************
 
-- 
2.40.0