Fixed notices order (ticket #9).

ChangeLog

@@ -6,6 +6,8 @@
 	* lib/extras.py: don't change the exception raised when fetching without a
 	result from NamedTupleCursor.
 
+	* psycopg/connection_int.c: fixed notices order (ticket #9).
+
 2010-11-10  Daniele Varrazzo  <daniele.varrazzo@gmail.com>
 
 	* psycopg/green.c: functions unused outside the module marked static.

NEWS-2.3

@@ -25,7 +25,9 @@ psycopg 2.3 aims to expose some new features introduced in PostgreSQL 9.0.
 
   - Fixed use of `PQfreemem` instead of `free` in binary typecaster.
   - Fixed access to freed memory in `conn_get_isolation_level()`.
-  - Fixed crash during Decimal adaptation with a few 2.5.x Python versions.
+  - Fixed crash during Decimal adaptation with a few 2.5.x Python versions
+    (ticket #7).
+  - Fixed notices order (ticket #9).
 
 
 What's new in psycopg 2.2.2

psycopg/connection_int.c

@@ -71,32 +71,41 @@ void
 conn_notice_process(connectionObject *self)
 {
     struct connectionObject_notice *notice;
-    PyObject *msg;
+    Py_ssize_t nnotices;
+
+    if (NULL == self->notice_pending) {
+        return;
+    }
 
     Py_BEGIN_ALLOW_THREADS;
     pthread_mutex_lock(&self->lock);
-
-    notice =  self->notice_pending;
-
-    while (notice != NULL) {
     Py_BLOCK_THREADS;
 
+    notice =  self->notice_pending;
+    nnotices = PyList_GET_SIZE(self->notice_list);
+
+    while (notice != NULL) {
+        PyObject *msg;
         msg = PyString_FromString(notice->message);
 
         Dprintf("conn_notice_process: %s", notice->message);
 
-        PyList_Append(self->notice_list, msg);
+        /* Respect the order in which notices were produced,
+           because in notice_list they are reversed (see ticket #9) */
+        PyList_Insert(self->notice_list, nnotices, msg);
         Py_DECREF(msg);
 
-        /* Remove the oldest item if the queue is getting too long. */
-        if (PyList_GET_SIZE(self->notice_list) > CONN_NOTICES_LIMIT)
-            PySequence_DelItem(self->notice_list, 0);
-
-        Py_UNBLOCK_THREADS;
-
         notice = notice->next;
     }
 
+    /* Remove the oldest item if the queue is getting too long. */
+    nnotices = PyList_GET_SIZE(self->notice_list);
+    if (nnotices > CONN_NOTICES_LIMIT) {
+        PySequence_DelSlice(self->notice_list,
+            0, nnotices - CONN_NOTICES_LIMIT);
+    }
+
+    Py_UNBLOCK_THREADS;
     pthread_mutex_unlock(&self->lock);
     Py_END_ALLOW_THREADS;
 

tests/test_connection.py

@@ -48,6 +48,32 @@ class ConnectionTests(unittest.TestCase):
         self.assert_(conn.notices)
         conn.close()
 
+    def test_notices_consistent_order(self):
+        conn = self.connect()
+        cur = conn.cursor()
+        cur.execute("create temp table table1 (id serial); create temp table table2 (id serial);")
+        cur.execute("create temp table table3 (id serial); create temp table table4 (id serial);")
+        self.assertEqual(4, len(conn.notices))
+        self.assert_('table1' in conn.notices[0])
+        self.assert_('table2' in conn.notices[1])
+        self.assert_('table3' in conn.notices[2])
+        self.assert_('table4' in conn.notices[3])
+        conn.close()
+
+    def test_notices_limited(self):
+        conn = self.connect()
+        cur = conn.cursor()
+        for i in range(0, 100, 10):
+            sql = " ".join(["create temp table table%d (id serial);" % j for j in range(i, i+10)])
+            cur.execute(sql)
+
+        self.assertEqual(50, len(conn.notices))
+        self.assert_('table50' in conn.notices[0], conn.notices[0])
+        self.assert_('table51' in conn.notices[1], conn.notices[1])
+        self.assert_('table98' in conn.notices[-2], conn.notices[-2])
+        self.assert_('table99' in conn.notices[-1], conn.notices[-1])
+        conn.close()
+
     def test_server_version(self):
         conn = self.connect()
         self.assert_(conn.server_version)