tests/basics: Add test for overriding a native base-class's init method.

tests/basics/subclass_native_init.py

@@ -0,0 +1,44 @@
+# test subclassing a native type and overriding __init__
+
+# overriding list.__init__()
+class L(list):
+    def __init__(self, a, b):
+        super().__init__([a, b])
+print(L(2, 3))
+
+# inherits implicitly from object
+class A:
+    def __init__(self):
+        print("A.__init__")
+        super().__init__()
+A()
+
+# inherits explicitly from object
+class B(object):
+    def __init__(self):
+        print("B.__init__")
+        super().__init__()
+B()
+
+# multiple inheritance with object explicitly mentioned
+class C:
+    pass
+class D(C, object):
+    def __init__(self):
+        print('D.__init__')
+        super().__init__()
+    def reinit(self):
+        print('D.foo')
+        super().__init__()
+a = D()
+a.__init__()
+a.reinit()
+
+# call __init__() after object is already init'd
+class L(list):
+    def reinit(self):
+        super().__init__(range(2))
+a = L(range(5))
+print(a)
+a.reinit()
+print(a)