test equality

pymongo/binary.py

@@ -45,12 +45,19 @@ class Binary(str):
             raise TypeError("subtype must be an instance of int")
         if subtype >= 256 or subtype < 0:
             raise ValueError("subtype must be contained in [0, 256)")
-        binary = str.__new__(cls, data)
-        binary.__subtype = subtype
-        return binary
+        self = str.__new__(cls, data)
+        self.__subtype = subtype
+        return self
 
     def subtype(self):
+        """Get the subtype of this binary data.
+        """
         return self.__subtype
 
+    def __eq__(self, other):
+        if isinstance(other, Binary):
+            return (self.__subtype, str(self)) == (other.__subtype, str(other))
+        return NotImplemented
+
     def __repr__(self):
         return "Binary(%s, %s)" % (str.__repr__(self), self.__subtype)

test/test_binary.py

@@ -50,6 +50,14 @@ class TestBinary(unittest.TestCase):
         c = Binary("hello", 100)
         self.assertEqual(c.subtype(), 100)
 
+    def test_equality(self):
+        b = Binary("hello")
+        c = Binary("hello", 100)
+        self.assertNotEqual(b, c)
+        self.assertEqual(c, Binary("hello", 100))
+        self.assertEqual(b, Binary("hello"))
+        self.assertNotEqual(b, Binary("hello "))
+
     def test_repr(self):
         b = Binary("hello world")
         self.assertEqual(repr(b), "Binary('hello world', 2)")