tests for Proxy

satella/coding/structures/proxy.py

@@ -31,8 +31,7 @@ class Proxy(tp.Generic[T]):
     Note that in-place operations will return the Proxy itself, whereas simple addition will shed
     this proxy, returning object wrapped plus something.
 
-    Note that proxies are considered to be the type of the object that they wrap,
-    as well as considered to be of type Proxy.
+    Only __isinstance__ check is not overridden, due to Python limitations.
 
     Please access this object in your descendant classes via
 
@@ -41,7 +40,7 @@ class Proxy(tp.Generic[T]):
     Please note that this class does not overload the descriptor protocol,
     not the pickle interface!
 
-    Note that this overloads both __repr__ and __str__, which may prove confusing.
+    Note that this overloads __repr__, __str__ and __dir__, which may prove confusing.
     Handle this in your descendant classes.
 
     :param object_to_wrap: object to wrap

tests/test_coding/test_proxy.py

@@ -6,7 +6,10 @@ from satella.coding.structures import Proxy
 
 class TestProxy(unittest.TestCase):
     def test_proxy(self):
+        a = Proxy(5.25, True)
+        self.assertIsInstance(a+2, Proxy)
         a = Proxy(5.25)
+        self.assertNotIsInstance(a+2, Proxy)
         self.assertEqual(int(a), 5)
         self.assertEqual(float(a), 5.25)
         self.assertEqual(a - 0.25, 5.0)