Fix crash if a DROP is attempted on an internally-dependent object.

Introduced in 8.4 rewrite of dependency.c.
Per bug #5072 from Amit Khandekar.

3 files changed, 22 insertions, 5 deletions

diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index dd2b29a43d..cb9a9c2675 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -559,7 +559,8 @@ findDependentObjects(const ObjectAddress *object,
 				{
 					char	   *otherObjDesc;
 
-					if (object_address_present(&otherObject, pendingObjects))
+					if (pendingObjects &&
+						object_address_present(&otherObject, pendingObjects))
 					{
 						systable_endscan(scan);
 						/* need to release caller's lock; see notes below */
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 2667a13e44..9244376a3b 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1424,10 +1424,10 @@ insert into rule_and_refint_t3 values (1, 12, 11, 'row3');
 insert into rule_and_refint_t3 values (1, 12, 12, 'row4');
 insert into rule_and_refint_t3 values (1, 11, 13, 'row5');
 ERROR:  insert or update on table "rule_and_refint_t3" violates foreign key constraint "rule_and_refint_t3_id3a_fkey1"
-DETAIL:  Key (id3a,id3c)=(1,13) is not present in table "rule_and_refint_t2".
+DETAIL:  Key (id3a, id3c)=(1, 13) is not present in table "rule_and_refint_t2".
 insert into rule_and_refint_t3 values (1, 13, 11, 'row6');
 ERROR:  insert or update on table "rule_and_refint_t3" violates foreign key constraint "rule_and_refint_t3_id3a_fkey"
-DETAIL:  Key (id3a,id3b)=(1,13) is not present in table "rule_and_refint_t1".
+DETAIL:  Key (id3a, id3b)=(1, 13) is not present in table "rule_and_refint_t1".
 create rule rule_and_refint_t3_ins as on insert to rule_and_refint_t3
 	where (exists (select 1 from rule_and_refint_t3
 			where (((rule_and_refint_t3.id3a = new.id3a)
@@ -1439,10 +1439,18 @@ create rule rule_and_refint_t3_ins as on insert to rule_and_refint_t3
 	and (rule_and_refint_t3.id3c = new.id3c));
 insert into rule_and_refint_t3 values (1, 11, 13, 'row7');
 ERROR:  insert or update on table "rule_and_refint_t3" violates foreign key constraint "rule_and_refint_t3_id3a_fkey1"
-DETAIL:  Key (id3a,id3c)=(1,13) is not present in table "rule_and_refint_t2".
+DETAIL:  Key (id3a, id3c)=(1, 13) is not present in table "rule_and_refint_t2".
 insert into rule_and_refint_t3 values (1, 13, 11, 'row8');
 ERROR:  insert or update on table "rule_and_refint_t3" violates foreign key constraint "rule_and_refint_t3_id3a_fkey"
-DETAIL:  Key (id3a,id3b)=(1,13) is not present in table "rule_and_refint_t1".
+DETAIL:  Key (id3a, id3b)=(1, 13) is not present in table "rule_and_refint_t1".
+--
+-- disallow dropping a view's rule (bug #5072)
+--
+create view fooview as select 'foo'::text;
+drop rule "_RETURN" on fooview;
+ERROR:  cannot drop rule _RETURN on view fooview because view fooview requires it
+HINT:  You can drop view fooview instead.
+drop view fooview;
 --
 -- check for planner problems with complex inherited UPDATES
 --
diff --git a/src/test/regress/sql/rules.sql b/src/test/regress/sql/rules.sql
index a522d52d19..c7cf788b20 100644
--- a/src/test/regress/sql/rules.sql
+++ b/src/test/regress/sql/rules.sql
@@ -852,6 +852,14 @@ insert into rule_and_refint_t3 values (1, 11, 13, 'row7');
 insert into rule_and_refint_t3 values (1, 13, 11, 'row8');
 
 --
+-- disallow dropping a view's rule (bug #5072)
+--
+
+create view fooview as select 'foo'::text;
+drop rule "_RETURN" on fooview;
+drop view fooview;
+
+--
 -- check for planner problems with complex inherited UPDATES
 --