Add regression tests for recent cursor/savepoint bug fixed by Alvaro and

Tom.

src/test/regress/expected/transactions.out

@@ -470,3 +470,50 @@ ROLLBACK;
 DROP TABLE foo;
 DROP TABLE baz;
 DROP TABLE barbaz;
+-- verify that cursors created during an aborted subtransaction are
+-- closed, but that we do not rollback the effect of any FETCHs
+-- performed in the aborted subtransaction
+begin;
+savepoint x;
+create table abc (a int);
+insert into abc values (5);
+insert into abc values (10);
+declare foo cursor for select * from abc;
+fetch from foo;
+ a 
+---
+ 5
+(1 row)
+
+rollback to x;
+-- should fail
+fetch from foo;
+ERROR:  cursor "foo" does not exist
+commit;
+begin;
+create table abc (a int);
+insert into abc values (5);
+insert into abc values (10);
+insert into abc values (15);
+declare foo cursor for select * from abc;
+fetch from foo;
+ a 
+---
+ 5
+(1 row)
+
+savepoint x;
+fetch from foo;
+ a  
+----
+ 10
+(1 row)
+
+rollback to x;
+fetch from foo;
+ a  
+----
+ 15
+(1 row)
+
+abort;

src/test/regress/sql/transactions.sql

@@ -290,3 +290,38 @@ ROLLBACK;
 DROP TABLE foo;
 DROP TABLE baz;
 DROP TABLE barbaz;
+
+-- verify that cursors created during an aborted subtransaction are
+-- closed, but that we do not rollback the effect of any FETCHs
+-- performed in the aborted subtransaction
+begin;
+
+savepoint x;
+create table abc (a int);
+insert into abc values (5);
+insert into abc values (10);
+declare foo cursor for select * from abc;
+fetch from foo;
+rollback to x;
+
+-- should fail
+fetch from foo;
+commit;
+
+begin;
+
+create table abc (a int);
+insert into abc values (5);
+insert into abc values (10);
+insert into abc values (15);
+declare foo cursor for select * from abc;
+
+fetch from foo;
+
+savepoint x;
+fetch from foo;
+rollback to x;
+
+fetch from foo;
+
+abort;