seberg
diff --git a/‎numpy/core/memmap.py
Lines changed: 18 additions & 12 deletions b/‎numpy/core/memmap.py
Lines changed: 18 additions & 12 deletions
diff --git a/‎numpy/core/tests/test_memmap.py
Lines changed: 6 additions & 1 deletion b/‎numpy/core/tests/test_memmap.py
Lines changed: 6 additions & 1 deletion
@@ -283,24 +283,30 @@ def __array_finalize__(self, obj):
             self.mode = None
 
     def __array_wrap__(self, arr, context=None):
-        # If the type is not memmap, then a user subclass may have some special
-        # functions that should be preserved to avoid a regression
-        if type(self) is not memmap:
-            r
10000
eturn arr.view(type=type(self))
-        return arr
+        # If the type is not memmap, then a user subclass may do some more
+        # things that need to be preserved. Otherwise, return a base array
+        # since it should not p
+        if type(self) is memmap and not np.may_share_memory(self, arr):
+            return arr
+        try:
+            return super(memmap, self).__array_wrap__(arr, context=context)
+        except TypeError:
+            return super(memmap, self).__array_wrap__(arr)
 
     def __array_prepare__(self, arr, context=None):
-        if type(self) is not memmap:
-            return arr.view(type=type(self))
-        # There is no use in making an array a memmap, since it does not own
-        # its memory.
-        return arr
+        # There is no need to make an array a memmap, but we still have to do
+        # it in case this is not of memmap type.
+        if type(self) is memmap and not np.may_share_memory(self, arr):
+            return arr
+        try:
+            return super(memmap, self).__array_prepare__(arr, context=context)
+        except TypeError:
+            return super(memmap, self).__array_prepare__(arr)
 
     def __getitem__(self, index):
-        # return an array if the result does not point to self's memory
         res = super(memmap, self).__getitem__(index)
         if type(res) is memmap and res._mmap is None:
-            return res.view(ndarray)
+            return res.view(type=ndarray)
         return res
 
     def flush(self):
 
@@ -116,7 +116,11 @@ def test_view(self):
         assert(new_array.base is fp)
 
     def test_to_array_conversions(self):
-        class MMSubclass(memmap):
+        class DummyInerhitance(np.ndarray):
+            def __array_wrap__(self, arr):
+                arr = super(DummyInerhitance, self).__array_wrap__(arr)
+                arr.info = 'set'
+        class MMSubclass(memmap, DummyInerhitance):
             pass
         m = memmap(self.tmpfp, dtype=self.dtype, shape=self.shape)
         r = m + 1
@@ -128,6 +132,7 @@ class MMSubclass(memmap):
         m = MMSubclass(self.tmpfp, dtype=self.dtype, shape=self.shape)
         r = m + 1
         assert_(isinstance(r, MMSubclass))
+        assert_(hasattr(r, 'info'))
         assert_(isinstance(m[:,[0,1]], MMSubclass))
 
 if __name__ == "__main__":