Added tes_old_pool_interface.

theano/tensor/signal/tests/test_pool.py

 from __future__ import absolute_import, print_function, division
 
 from itertools import product
+import os
 import unittest
+from six.moves import cPickle
 import six.moves.builtins as builtins
+import sys
 
 import numpy
 
@@ -821,9 +824,9 @@ class TestDownsampleFactorMax(utt.InferShapeTester):
             for mode in ['max', 'sum', 'average_inc_pad', 'average_exc_pad']:
                 y = pool_2d(x, window_size, ignore_border, stride, padding,
                             mode)
-                dy = theano.gradient.grad(y.sum(), x)
+                dx = theano.gradient.grad(y.sum(), x)
                 var_fct = theano.function([x, window_size, stride, padding],
-                                          [y, dy])
+                                          [y, dx])
                 for ws in (4, 2, 5):
                     for st in (2, 3):
                         for pad in (0, 1):
@@ -833,13 +836,29 @@ class TestDownsampleFactorMax(utt.InferShapeTester):
                                 continue
                             y = pool_2d(x, (ws, ws), ignore_border, (st, st),
                                         (pad, pad), mode)
-                            dy = theano.gradient.grad(y.sum(), x)
-                            fix_fct = theano.function([x], [y, dy])
-                            var_y, var_dy = var_fct(data, (ws, ws), (st, st),
+                            dx = theano.gradient.grad(y.sum(), x)
+                            fix_fct = theano.function([x], [y, dx])
+                            var_y, var_dx = var_fct(data, (ws, ws), (st, st),
                                                     (pad, pad))
-                            fix_y, fix_dy = fix_fct(data)
+                            fix_y, fix_dx = fix_fct(data)
                             utt.assert_allclose(var_y, fix_y)
-                            utt.assert_allclose(var_dy, fix_dy)
+                            utt.assert_allclose(var_dx, fix_dx)
+
+    def test_old_pool_interface(self):
+        testfile_dir = os.path.dirname(os.path.realpath(__file__))
+        fname = 'old_pool_interface.pkl'
+        with open(os.path.join(testfile_dir, fname), 'rb') as fp:
+            try:
+                cPickle.load(fp)
+            except ImportError:
+                # Windows sometimes fail with nonsensical errors like:
+                #   ImportError: No module named type
+                #   ImportError: No module named copy_reg
+                # when "type" and "copy_reg" are builtin modules.
+                if sys.platform == 'win32':
+                    exc_type, exc_value, exc_trace = sys.exc_info()
+                    reraise(SkipTest, exc_value, exc_trace)
+                raise
 
     def test_DownsampleFactorMaxGrad(self):
         im = theano.tensor.tensor4()