Fixed some broken tests when scipy is not available

theano/sandbox/linalg/tests/test_linalg.py

 import numpy
 
 import theano
+import theano.sparse # To know if scipy is available.
 from theano import tensor, function
 from theano.tensor.basic import _allclose
 
 from theano.sandbox.linalg.ops import *
 
+from nose.plugins.skip import SkipTest
+
+
 if 0:
     def test_cholesky():
         #TODO: test upper and lower triangular
@@ -59,6 +63,11 @@ def test_inverse_grad():
 
 
 def test_det_grad():
+    # If scipy is not available, this test will fail, thus we skip it.
+    # Note that currently we re-use the `enable_sparse` flag, but it may be
+    # cleaner to have a different `scipy_available` flag in the future.
+    if not theano.sparse.enable_sparse:
+        raise SkipTest('Scipy is not available')
     rng = numpy.random.RandomState(1234)
 
     r = rng.randn(5,5)

theano/sparse/sandbox/test_sp.py

 import sys
+
+from nose.plugins.skip import SkipTest
+import theano.sparse
+if not theano.sparse.enable_sparse:
+    raise SkipTest('Optional package sparse disabled')
+
 from theano import function, Mode
 from theano.gof import OpWiseCLinker
 import theano, numpy
 import theano.tensor as T
-import theano.sparse
 import scipy.sparse
 
 from scipy.signal import convolve2d

theano/tensor/nnet/tests/test_conv3d.py

 import unittest
 import theano
 import theano.tensor as T
-from theano import function
+from theano import function, shared
 from theano.tests import unittest_tools as utt
 from theano.tensor.nnet.ConvTransp3D import convTransp3D
 from theano.tensor.nnet.ConvGrad3D import convGrad3D
 from theano.tensor.nnet.Conv3D import conv3D
 import numpy as N
 import copy
-from scipy import sparse
-from theano import shared
+import theano.sparse
+if theano.sparse.enable_sparse:
+    from scipy import sparse
+from nose.plugins.skip import SkipTest
 
 floatX = theano.config.floatX
 
@@ -311,6 +313,8 @@ class TestConv3D(unittest.TestCase):
 
     def test_c_against_sparse_mat_transp_mul(self):
     #like test_c_against_mat_transp_mul but using a sparse matrix and a kernel that is smaller than the image
+        if not theano.sparse.enable_sparse:
+            raise SkipTest('Optional package sparse disabled')
 
         batchSize    = self.rng.randint(1,3)
         filterWidth  = self.rng.randint(1,8)

theano/tensor/tests/test_sharedvar.py

@@ -7,6 +7,7 @@ from theano.gof.python25 import all
 from theano import tensor
 from theano.tests import unittest_tools as utt
 from theano.misc.may_share_memory import may_share_memory
+import theano.sparse
 
 utt.seed_rng()
 
@@ -445,7 +446,8 @@ def makeSharedTester(shared_constructor_,
                 topo_cst[0].op == theano.compile.function_module.deep_copy_op
 
             # Test that we can take the grad.
-            if isinstance(x1_specify_shape.type, theano.sparse.SparseType):
+            if (theano.sparse.enable_sparse and
+                isinstance(x1_specify_shape.type, theano.sparse.SparseType)):
                 #SparseVariable don't support sum for now.
                 assert not hasattr(x1_specify_shape, 'sum')
             else: