change of variable name and some some docs in test_reallocation()

theano/gof/tests/test_vm.py

@@ -368,6 +368,9 @@ def test_vm_gc():
 
 
 def test_reallocation():
+    """
+    test share memory.
+    """
     x = tensor.scalar('x')
     y = tensor.scalar('y')
     z = tensor.tanh(3 * x + y) + tensor.cosh(x + 5 * y)
@@ -384,6 +387,10 @@ def test_reallocation():
         storage_map = f.fn.storage_map
 
         def check_storage(storage_map):
+            """
+            Return [True, same_value] if two storages have same value,
+            otherwise return [False, None]
+            """
             from theano.tensor.var import TensorConstant
             for i in storage_map:
                 if not isinstance(i, TensorConstant):
@@ -395,6 +402,7 @@ def test_reallocation():
                             return [True, storage_map[o][0]]
             return [False, None]
 
+        # assert there's same value in strage_map
         assert check_storage(storage_map)[0]
         assert len(set(id(v) for v in
                        itervalues(storage_map))) < len(storage_map)