Add test cases for #698 and #757.

theano/sandbox/cuda/tests/test_var.py

 import numpy
 from nose.plugins.skip import SkipTest
 
+import theano
 from theano.sandbox.cuda.var import float32_shared_constructor as f32sc
 from theano.sandbox.cuda import CudaNdarrayType, cuda_available
 
@@ -34,3 +35,35 @@ def test_float32_shared_constructor():
     assert eq(
             f32sc(numpy.zeros((2,3,4,5), dtype='float32')).type,
             CudaNdarrayType((False,)*4))
+
+def test_givens():
+    # Test that you can use a TensorType expression to replace a
+    # CudaNdarrayType in the givens dictionary.
+    # This test case uses code mentionned in #757
+    data = numpy.float32([1,2,3,4])
+    x = f32sc(data)
+    y = x**2
+    f = theano.function([x], y, givens={x:x+1})
+
+def test_updates():
+    # Test that you can use a TensorType expression to update a
+    # CudaNdarrayType in the updates dictionary.
+    data = numpy.float32([1,2,3,4])
+    x = f32sc(data)
+    y = x**2
+    f = theano.function([], y, updates={x:x+1})
+
+def test_updates2():
+    # Test that you can use a TensorType expression to update a
+    # CudaNdarrayType in the updates dictionary.
+    # This test case uses code mentionned in #698
+    data = numpy.random.rand(10,10).astype('float32')
+    output_var = f32sc(name="output",
+            value=numpy.zeros((10,10), 'float32'))
+
+    x = theano.tensor.fmatrix('x')
+    output_updates = {output_var:x**2}
+    output_givens = {x:data}
+    output_func = theano.function(inputs=[], outputs=[],
+            updates=output_updates, givens=output_givens)
+    output_func()