Improved tests.

Author: vsajip

Lib/ctypes/test/test_structures.py

@@ -603,6 +603,7 @@ class Test5(Structure):
             _fields_ = [
                 ('an_int', c_int),
                 ('nested', Nested2),
+                ('another_int', c_int),
             ]
 
         test4 = Test4()
@@ -623,6 +624,38 @@ class Test5(Structure):
         self.assertEqual(ctx.exception.args[0], 'item 1 in _argtypes_ passes '
                          'a union by value, which is unsupported.')
 
+        # passing by reference should be OK
+        test4.a_long = 12345;
+        func = dll._testfunc_union_by_reference1
+        func.restype = c_long
+        func.argtypes = (POINTER(Test4),)
+        result = func(byref(test4))
+        self.assertEqual(result, 12345)
+        self.assertEqual(test4.a_long, 0)
+        self.assertEqual(test4.a_struct.an_int, 0)
+        self.assertEqual(test4.a_struct.another_int, 0)
+        test4.a_struct.an_int = 0x12340000
+        test4.a_struct.another_int = 0x5678
+        func = dll._testfunc_union_by_reference2
+        func.restype = c_long
+        func.argtypes = (POINTER(Test4),)
+        result = func(byref(test4))
+        self.assertEqual(result, 0x12345678)
+        self.assertEqual(test4.a_long, 0)
+        self.assertEqual(test4.a_struct.an_int, 0)
+        self.assertEqual(test4.a_struct.another_int, 0)
+        test5.an_int = 0x12000000
+        test5.nested.an_int = 0x345600
+        test5.another_int = 0x78
+        func = dll._testfunc_union_by_reference3
+        func.restype = c_long
+        func.argtypes = (POINTER(Test5),)
+        result = func(byref(test5))
+        self.assertEqual(result, 0x12345678)
+        self.assertEqual(test5.an_int, 0)
+        self.assertEqual(test5.nested.an_int, 0)
+        self.assertEqual(test5.another_int, 0)
+
 class PointerMemberTestCase(unittest.TestCase):
 
     def test(self):

Modules/_ctypes/_ctypes_test.c

@@ -145,6 +145,7 @@ typedef struct {
         int an_int;
         Test4 a_union;
     } nested;
+    int another_int;
 } Test5;
 
 EXPORT(long)
@@ -169,6 +170,30 @@ _testfunc_union_by_value2(Test5 in) {
     return result;
 }
 
+EXPORT(long)
+_testfunc_union_by_reference1(Test4 *in) {
+    long result = in->a_long;
+
+    memset(in, 0, sizeof(Test4));
+    return result;
+}
+
+EXPORT(long)
+_testfunc_union_by_reference2(Test4 *in) {
+    long result = in->a_struct.an_int + in->a_struct.another_int;
+
+    memset(in, 0, sizeof(Test4));
+    return result;
+}
+
+EXPORT(long)
+_testfunc_union_by_reference3(Test5 *in) {
+    long result = in->an_int + in->nested.an_int + in->another_int;
+
+    memset(in, 0, sizeof(Test5));
+    return result;
+}
+
 EXPORT(void)testfunc_array(int values[4])
 {
     printf("testfunc_array %d %d %d %d\n",