bpo-34041: Allow creating deterministic functions in Connection.create_function() (GH-8086)

1 files changed, 28 insertions, 4 deletions

diff --git a/Modules/_sqlite/connection.c b/Modules/_sqlite/connection.c
index ef2daeb..b8470df 100644
--- a/Modules/_sqlite/connection.c
+++ b/Modules/_sqlite/connection.c
@@ -810,24 +810,48 @@ static void _pysqlite_drop_unused_cursor_references(pysqlite_Connection* self)
 
 PyObject* pysqlite_connection_create_function(pysqlite_Connection* self, PyObject* args, PyObject* kwargs)
 {
-    static char *kwlist[] = {"name", "narg", "func", NULL, NULL};
+    static char *kwlist[] = {"name", "narg", "func", "deterministic", NULL};
 
     PyObject* func;
     char* name;
     int narg;
     int rc;
+    int deterministic = 0;
+    int flags = SQLITE_UTF8;
 
     if (!pysqlite_check_thread(self) || !pysqlite_check_connection(self)) {
         return NULL;
     }
 
-    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "siO", kwlist,
-                                     &name, &narg, &func))
+    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "siO|$p", kwlist,
+                                     &name, &narg, &func, &deterministic))
     {
         return NULL;
     }
 
-    rc = sqlite3_create_function(self->db, name, narg, SQLITE_UTF8, (void*)func, _pysqlite_func_callback, NULL, NULL);
+    if (deterministic) {
+#if SQLITE_VERSION_NUMBER < 3008003
+        PyErr_SetString(pysqlite_NotSupportedError,
+                        "deterministic=True requires SQLite 3.8.3 or higher");
+        return NULL;
+#else
+        if (sqlite3_libversion_number() < 3008003) {
+            PyErr_SetString(pysqlite_NotSupportedError,
+                            "deterministic=True requires SQLite 3.8.3 or higher");
+            return NULL;
+        }
+        flags |= SQLITE_DETERMINISTIC;
+#endif
+    }
+
+    rc = sqlite3_create_function(self->db,
+                                 name,
+                                 narg,
+                                 flags,
+                                 (void*)func,
+                                 _pysqlite_func_callback,
+                                 NULL,
+                                 NULL);
 
     if (rc != SQLITE_OK) {
         /* Workaround for SQLite bug: no error code or string is available here */