1 files changed, 50 insertions, 0 deletions
diff --git a/lib/python2.7/ctypes/test/test_struct_fields.py b/lib/python2.7/ctypes/test/test_struct_fields.py
new file mode 100644
index 0000000..22eb3b0
--- /dev/null
+++ b/lib/python2.7/ctypes/test/test_struct_fields.py
@@ -0,0 +1,50 @@
+import unittest
+from ctypes import *
+
+class StructFieldsTestCase(unittest.TestCase):
+    # Structure/Union classes must get 'finalized' sooner or
+    # later, when one of these things happen:
+    #
+    # 1. _fields_ is set.
+    # 2. An instance is created.
+    # 3. The type is used as field of another Structure/Union.
+    # 4. The type is subclassed
+    #
+    # When they are finalized, assigning _fields_ is no longer allowed.
+
+    def test_1_A(self):
+        class X(Structure):
+            pass
+        self.assertEqual(sizeof(X), 0) # not finalized
+        X._fields_ = [] # finalized
+        self.assertRaises(AttributeError, setattr, X, "_fields_", [])
+
+    def test_1_B(self):
+        class X(Structure):
+            _fields_ = [] # finalized
+        self.assertRaises(AttributeError, setattr, X, "_fields_", [])
+
+    def test_2(self):
+        class X(Structure):
+            pass
+        X()
+        self.assertRaises(AttributeError, setattr, X, "_fields_", [])
+
+    def test_3(self):
+        class X(Structure):
+            pass
+        class Y(Structure):
+            _fields_ = [("x", X)] # finalizes X
+        self.assertRaises(AttributeError, setattr, X, "_fields_", [])
+
+    def test_4(self):
+        class X(Structure):
+            pass
+        class Y(X):
+            pass
+        self.assertRaises(AttributeError, setattr, X, "_fields_", [])
+        Y._fields_ = []
+        self.assertRaises(AttributeError, setattr, X, "_fields_", [])
+
+if __name__ == "__main__":
+    unittest.main()