Merge branch 'fix-746'

NEWS

@@ -21,6 +21,13 @@ Other changes:
   install``.
 
 
+What's new in psycopg 2.7.6
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+- Close named cursors if exist, even if `~cursor.execute()` wasn't called
+  (:ticket:`#746`).
+
+
 What's new in psycopg 2.7.5
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 

psycopg/cursor_type.c

@@ -49,21 +49,21 @@
 static PyObject *
 psyco_curs_close(cursorObject *self)
 {
+    PyObject *rv = NULL;
+    char *lname = NULL;
+
     EXC_IF_ASYNC_IN_PROGRESS(self, close);
 
     if (self->closed) {
+        rv = Py_None;
+        Py_INCREF(rv);
         goto exit;
     }
 
     if (self->qname != NULL) {
-        char buffer[128];
+        char buffer[256];
         PGTransactionStatusType status;
 
-        if (!self->query) {
-            Dprintf("skipping named cursor close because unused");
-            goto close;
-        }
-
         if (self->conn) {
             status = PQtransactionStatus(self->conn->pgconn);
         }
@@ -77,17 +77,45 @@ psyco_curs_close(cursorObject *self)
             goto close;
         }
 
+        /* We should close a server-side cursor only if exists, or we get an
+         * error (#716). If we execute()d the cursor should exist alright, but
+         * if we didn't there is still the expectation that the cursor is
+         * closed (#746).
+         *
+         * So if we didn't execute() check for the cursor existence before
+         * closing it (the view exists since PG 8.2 according to docs).
+         */
+        if (!self->query && self->conn->server_version >= 80200) {
+            if (!(lname = psycopg_escape_string(
+                    self->conn, self->name, -1, NULL, NULL))) {
+                goto exit;
+            }
+            PyOS_snprintf(buffer, sizeof(buffer),
+                "SELECT 1 FROM pg_catalog.pg_cursors where name = %s",
+                lname);
+            if (pq_execute(self, buffer, 0, 0, 1) == -1) { goto exit; }
+
+            if (self->rowcount == 0) {
+                Dprintf("skipping named cursor close because not existing");
+                goto close;
+            }
+        }
+
         EXC_IF_NO_MARK(self);
-        PyOS_snprintf(buffer, 127, "CLOSE %s", self->qname);
+        PyOS_snprintf(buffer, sizeof(buffer), "CLOSE %s", self->qname);
-        if (pq_execute(self, buffer, 0, 0, 1) == -1) return NULL;
+        if (pq_execute(self, buffer, 0, 0, 1) == -1) { goto exit; }
     }
 
 close:
     self->closed = 1;
     Dprintf("psyco_curs_close: cursor at %p closed", self);
 
+    rv = Py_None;
+    Py_INCREF(rv);
+
 exit:
-    Py_RETURN_NONE;
+    PyMem_Free(lname);
+    return rv;
 }
 
 
@@ -742,7 +770,7 @@ psyco_curs_fetchone(cursorObject *self)
         EXC_IF_NO_MARK(self);
         EXC_IF_ASYNC_IN_PROGRESS(self, fetchone);
         EXC_IF_TPC_PREPARED(self->conn, fetchone);
-        PyOS_snprintf(buffer, 127, "FETCH FORWARD 1 FROM %s", self->qname);
+        PyOS_snprintf(buffer, sizeof(buffer), "FETCH FORWARD 1 FROM %s", self->qname);
         if (pq_execute(self, buffer, 0, 0, self->withhold) == -1) return NULL;
         if (_psyco_curs_prefetch(self) < 0) return NULL;
     }
@@ -791,7 +819,7 @@ psyco_curs_next_named(cursorObject *self)
     if (self->row >= self->rowcount) {
         char buffer[128];
 
-        PyOS_snprintf(buffer, 127, "FETCH FORWARD %ld FROM %s",
+        PyOS_snprintf(buffer, sizeof(buffer), "FETCH FORWARD %ld FROM %s",
             self->itersize, self->qname);
         if (pq_execute(self, buffer, 0, 0, self->withhold) == -1) return NULL;
         if (_psyco_curs_prefetch(self) < 0) return NULL;
@@ -860,7 +888,7 @@ psyco_curs_fetchmany(cursorObject *self, PyObject *args, PyObject *kwords)
         EXC_IF_NO_MARK(self);
         EXC_IF_ASYNC_IN_PROGRESS(self, fetchmany);
         EXC_IF_TPC_PREPARED(self->conn, fetchone);
-        PyOS_snprintf(buffer, 127, "FETCH FORWARD %d FROM %s",
+        PyOS_snprintf(buffer, sizeof(buffer), "FETCH FORWARD %d FROM %s",
             (int)size, self->qname);
         if (pq_execute(self, buffer, 0, 0, self->withhold) == -1) { goto exit; }
         if (_psyco_curs_prefetch(self) < 0) { goto exit; }
@@ -936,7 +964,7 @@ psyco_curs_fetchall(cursorObject *self)
         EXC_IF_NO_MARK(self);
         EXC_IF_ASYNC_IN_PROGRESS(self, fetchall);
         EXC_IF_TPC_PREPARED(self->conn, fetchall);
-        PyOS_snprintf(buffer, 127, "FETCH FORWARD ALL FROM %s", self->qname);
+        PyOS_snprintf(buffer, sizeof(buffer), "FETCH FORWARD ALL FROM %s", self->qname);
         if (pq_execute(self, buffer, 0, 0, self->withhold) == -1) { goto exit; }
         if (_psyco_curs_prefetch(self) < 0) { goto exit; }
     }
@@ -1233,11 +1261,11 @@ psyco_curs_scroll(cursorObject *self, PyObject *args, PyObject *kwargs)
         EXC_IF_TPC_PREPARED(self->conn, scroll);
 
         if (strcmp(mode, "absolute") == 0) {
-            PyOS_snprintf(buffer, 127, "MOVE ABSOLUTE %d FROM %s",
+            PyOS_snprintf(buffer, sizeof(buffer), "MOVE ABSOLUTE %d FROM %s",
                 value, self->qname);
         }
         else {
-            PyOS_snprintf(buffer, 127, "MOVE %d FROM %s", value, self->qname);
+            PyOS_snprintf(buffer, sizeof(buffer), "MOVE %d FROM %s", value, self->qname);
         }
         if (pq_execute(self, buffer, 0, 0, self->withhold) == -1) return NULL;
         if (_psyco_curs_prefetch(self) < 0) return NULL;

tests/test_cursor.py

@@ -436,11 +436,24 @@ class CursorTests(ConnectingTestCase):
         self.assertEqual([(2,), (3,), (4,)], cur2.fetchmany(3))
         self.assertEqual([(5,), (6,), (7,)], cur2.fetchall())
 
-    @skip_before_postgres(8, 0)
+    @skip_before_postgres(8, 2)
     def test_named_noop_close(self):
         cur = self.conn.cursor('test')
         cur.close()
 
+    @skip_before_postgres(8, 2)
+    def test_stolen_named_cursor_close(self):
+        cur1 = self.conn.cursor()
+        cur1.execute("DECLARE test CURSOR WITHOUT HOLD "
+            " FOR SELECT generate_series(1,7)")
+        cur2 = self.conn.cursor('test')
+        cur2.close()
+
+        cur1.execute("DECLARE test CURSOR WITHOUT HOLD "
+            " FOR SELECT generate_series(1,7)")
+        cur2 = self.conn.cursor('test')
+        cur2.close()
+
     @skip_before_postgres(8, 0)
     def test_scroll(self):
         cur = self.conn.cursor()

tests/test_with.py

@@ -215,7 +215,7 @@ class WithCursorTestCase(WithTestCase):
         else:
             self.fail("where is my exception?")
 
-    @skip_before_postgres(8, 0)
+    @skip_before_postgres(8, 2)
     def test_named_with_noop(self):
         with self.conn.cursor('named') as cur:
             pass