Merged revisions 74917 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r74917 | thomas.heller | 2009-09-18 20:55:17 +0200 (Fr, 18 Sep 2009) | 3 lines

  Issue #5042: Structure sub-subclass does now initialize correctly with
  base class positional arguments.
........

diff --git a/Lib/ctypes/test/test_structures.py b/Lib/ctypes/test/test_structures.py
index 0c5a3477630e5f826b0d01ff264250397bba9996..d4541a9e94d34f8e779602af59bd73e7374267c1 100644 (file)
--- a/Lib/ctypes/test/test_structures.py
+++ b/Lib/ctypes/test/test_structures.py
@@ -355,6 +355,25 @@ class StructureTestCase(unittest.TestCase):
         self.failUnless("from_address" in dir(type(Structure)))
         self.failUnless("in_dll" in dir(type(Structure)))
 
+    def test_positional_args(self):
+        # see also http://bugs.python.org/issue5042
+        class W(Structure):
+            _fields_ = [("a", c_int), ("b", c_int)]
+        class X(W):
+            _fields_ = [("c", c_int)]
+        class Y(X):
+            pass
+        class Z(Y):
+            _fields_ = [("d", c_int), ("e", c_int), ("f", c_int)]
+
+        z = Z(1, 2, 3, 4, 5, 6)
+        self.failUnlessEqual((z.a, z.b, z.c, z.d, z.e, z.f),
+                             (1, 2, 3, 4, 5, 6))
+        z = Z(1)
+        self.failUnlessEqual((z.a, z.b, z.c, z.d, z.e, z.f),
+                             (1, 0, 0, 0, 0, 0))
+        self.assertRaises(TypeError, lambda: Z(1, 2, 3, 4, 5, 6, 7))
+
 class PointerMemberTestCase(unittest.TestCase):
 
     def test(self):

diff --git a/Misc/NEWS b/Misc/NEWS
index c3c105b3175fada35cad3eaa2689425960d0da98..170cde7b6e843162300d938e10766d6d91942bcc 100644 (file)
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -82,6 +82,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #5042: Structure sub-subclass does now initialize correctly
+  with base class positional arguments.
+
 - Issue #6938: Fix a TypeError in string formatting of a multiprocessing
   debug message.
 

diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
index 6764c21ed5919a95e2fd64609a2f345b0b790b48..b6937a87c8c82e77c7ffd4f58609fcd3a4fed324 100644 (file)
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -4017,82 +4017,97 @@ IBUG(char *msg)
        return -1;
 }
 
+/*
+  This function is called to initialize a Structure or Union with positional
+  arguments. It calls itself recursively for all Structure or Union base
+  classes, then retrieves the _fields_ member to associate the argument
+  position with the correct field name.
+
+  Returns -1 on error, or the index of next argument on success.
+ */
 static int
-Struct_init(PyObject *self, PyObject *args, PyObject *kwds)
+_init_pos_args(PyObject *self, PyTypeObject *type,
+              PyObject *args, PyObject *kwds,
+              int index)
 {
-       int i;
+       StgDictObject *dict;
        PyObject *fields;
+       int i;
+
+       if (PyType_stgdict((PyObject *)type->tp_base)) {
+               index = _init_pos_args(self, type->tp_base,
+                                      args, kwds,
+                                      index);
+               if (index == -1)
+                       return -1;
+       }
+
+       dict = PyType_stgdict((PyObject *)type);
+       fields = PyDict_GetItemString((PyObject *)dict, "_fields_");
+       if (fields == NULL)
+               return index;
+
+       for (i = 0;
+            i < dict->length && (i+index) < PyTuple_GET_SIZE(args);
+            ++i) {
+               PyObject *pair = PySequence_GetItem(fields, i);
+               PyObject *name, *val;
+               int res;
+               if (!pair)
+                       return -1;
+               name = PySequence_GetItem(pair, 0);
+               if (!name) {
+                       Py_DECREF(pair);
+                       return -1;
+               }
+               val = PyTuple_GET_ITEM(args, i + index);
+               if (kwds && PyDict_GetItem(kwds, name)) {
+                       char *field = PyString_AsString(name);
+                       if (field == NULL) {
+                               PyErr_Clear();
+                               field = "???";
+                       }
+                       PyErr_Format(PyExc_TypeError,
+                                    "duplicate values for field '%s'",
+                                    field);
+                       Py_DECREF(pair);
+                       Py_DECREF(name);
+                       return -1;
+               }
+               
+               res = PyObject_SetAttr(self, name, val);
+               Py_DECREF(pair);
+               Py_DECREF(name);
+               if (res == -1)
+                       return -1;
+       }
+       return index + dict->length;
+}
+
+static int
+Struct_init(PyObject *self, PyObject *args, PyObject *kwds)
+{
+       StgDictObject *stgdict = PyObject_stgdict(self);
 
 /* Optimization possible: Store the attribute names _fields_[x][0]
  * in C accessible fields somewhere ?
  */
 
-/* Check this code again for correctness! */
-
        if (!PyTuple_Check(args)) {
                PyErr_SetString(PyExc_TypeError,
                                "args not a tuple?");
                return -1;
        }
        if (PyTuple_GET_SIZE(args)) {
-               fields = PyObject_GetAttrString(self, "_fields_");
-               if (!fields) {
-                       PyErr_Clear();
-                       fields = PyTuple_New(0);
-                       if (!fields)
-                               return -1;
-               }
-
-               if (PyTuple_GET_SIZE(args) > PySequence_Length(fields)) {
-                       Py_DECREF(fields);
+               int res = _init_pos_args(self, Py_TYPE(self),
+                                        args, kwds, 0);
+               if (res == -1)
+                       return -1;
+               if (res < PyTuple_GET_SIZE(args)) {
                        PyErr_SetString(PyExc_TypeError,
                                        "too many initializers");
                        return -1;
                }
-
-               for (i = 0; i < PyTuple_GET_SIZE(args); ++i) {
-                       PyObject *pair = PySequence_GetItem(fields, i);
-                       PyObject *name;
-                       PyObject *val;
-                       if (!pair) {
-                               Py_DECREF(fields);
-                               return IBUG("_fields_[i] failed");
-                       }
-
-                       name = PySequence_GetItem(pair, 0);
-                       if (!name) {
-                               Py_DECREF(pair);
-                               Py_DECREF(fields);
-                               return IBUG("_fields_[i][0] failed");
-                       }
-
-                       if (kwds && PyDict_GetItem(kwds, name)) {
-                               char *field = PyString_AsString(name);
-                               if (field == NULL) {
-                                       PyErr_Clear();
-                                       field = "???";
-                               }
-                               PyErr_Format(PyExc_TypeError,
-                                            "duplicate values for field %s",
-                                            field);
-                               Py_DECREF(pair);
-                               Py_DECREF(name);
-                               Py_DECREF(fields);
-                               return -1;
-                       }
-
-                       val = PyTuple_GET_ITEM(args, i);
-                       if (-1 == PyObject_SetAttr(self, name, val)) {
-                               Py_DECREF(pair);
-                               Py_DECREF(name);
-                               Py_DECREF(fields);
-                               return -1;
-                       }
-
-                       Py_DECREF(name);
-                       Py_DECREF(pair);
-               }
-               Py_DECREF(fields);
        }
 
        if (kwds) {