Skip a test if cuda isn't available.

theano/sandbox/cuda/tests/test_type.py

 import os.path
 
+from nose.plugins.skip import SkipTest
 from nose.tools import assert_raises
 import numpy
 
@@ -8,8 +9,10 @@ from theano.compat import PY3
 from theano.misc.pkl_utils import CompatUnpickler
 from theano.sandbox.cuda import cuda_available
 
-if cuda_available:
-    from theano.sandbox.cuda import CudaNdarray
+if not cuda_available:
+    raise SkipTest('Optional package cuda disabled')
+
+from theano.sandbox.cuda import CudaNdarray
 
 # testfile created on cuda enabled machine using
 # >>> with open('CudaNdarray.pkl', 'wb') as fp: