Don't throw an error for LOCK TABLE on a self-referential view.

LOCK TABLE has complained about "infinite recursion" when applied
to a self-referential view, ever since we made it recurse into views
in v11.  However, that breaks pg_dump's new assumption that it's
okay to lock every relation.  There doesn't seem to be any good
reason to throw an error: if we just abandon the recursion, we've
still satisfied the requirement of locking every referenced relation.

Per bug #16703 from Andrew Bille (via Alexander Lakhin).

Discussion: https://postgr.es/m/16703-e348f58aab3cf6cc@postgresql.org

2 files changed, 2 insertions, 4 deletions

diff --git a/src/test/regress/expected/lock.out b/src/test/regress/expected/lock.out
index 1d6a4e9f1e0..f39280a4fa6 100644
--- a/src/test/regress/expected/lock.out
+++ b/src/test/regress/expected/lock.out
@@ -124,16 +124,14 @@ select relname from pg_locks l, pg_class c
 (2 rows)
 
 ROLLBACK;
--- detecting infinite recursions in view definitions
+-- Verify that we cope with infinite recursion in view definitions.
 CREATE OR REPLACE VIEW lock_view2 AS SELECT * from lock_view3;
 BEGIN TRANSACTION;
 LOCK TABLE lock_view2 IN EXCLUSIVE MODE;
-ERROR:  infinite recursion detected in rules for relation "lock_view2"
 ROLLBACK;
 CREATE VIEW lock_view7 AS SELECT * from lock_view2;
 BEGIN TRANSACTION;
 LOCK TABLE lock_view7 IN EXCLUSIVE MODE;
-ERROR:  infinite recursion detected in rules for relation "lock_view2"
 ROLLBACK;
 -- Verify that we can lock a table with inheritance children.
 CREATE TABLE lock_tbl2 (b BIGINT) INHERITS (lock_tbl1);
diff --git a/src/test/regress/sql/lock.sql b/src/test/regress/sql/lock.sql
index 98d13fc8e1e..4f032f1c2e4 100644
--- a/src/test/regress/sql/lock.sql
+++ b/src/test/regress/sql/lock.sql
@@ -87,7 +87,7 @@ select relname from pg_locks l, pg_class c
  where l.relation = c.oid and relname like '%lock_%' and mode = 'ExclusiveLock'
  order by relname;
 ROLLBACK;
--- detecting infinite recursions in view definitions
+-- Verify that we cope with infinite recursion in view definitions.
 CREATE OR REPLACE VIEW lock_view2 AS SELECT * from lock_view3;
 BEGIN TRANSACTION;
 LOCK TABLE lock_view2 IN EXCLUSIVE MODE;