#2801, minor fix

theano/tensor/opt.py

@@ -1895,11 +1895,14 @@ def local_track_shape_i(node):
         return [shape_feature.shape_of[replacement][node.op.i]]
 
 
-# Subtensor(SetSubtensor(x, y, idx), idx) -> y
 @register_specialize
 @register_canonicalize
 @gof.local_optimizer([Subtensor])
 def local_subtensor_inc_subtensor(node):
+    """
+    Subtensor(SetSubtensor(x, y, idx), idx) -> y
+
+    """
     if isinstance(node.op, Subtensor):
         x = node.inputs[0]
         if not x.owner or not isinstance(x.owner.op, IncSubtensor):

theano/tensor/tests/test_opt.py

@@ -1956,7 +1956,7 @@ def test_subtensor_inc_subtensor():
     v = tensor.tensor3('v')
     y = tensor.set_subtensor(x[i1, :i2, i3:, ::i4], v)
     z = y[i1, :i2, i3:, ::i4]
-    mode = theano.compile.mode.get_mode('FAST_COMPILE').including('local_subtensor_inc_subtensor')
+    mode = theano.compile.mode.get_default_mode().including('local_subtensor_inc_subtensor')
     f = theano.function([x, i1, i2, i3, i4, v], z, mode=mode)
     prog = f.maker.fgraph.toposort()
     assert len(prog) == 1
@@ -1964,7 +1964,7 @@ def test_subtensor_inc_subtensor():
 
     # case not use this optimization
     z = y[i1, :i3, i2:, ::i4]
-    mode = theano.compile.mode.get_mode('FAST_COMPILE').including('local_subtensor_inc_subtensor')
+    mode = theano.compile.mode.get_default_mode().including('local_subtensor_inc_subtensor')
     f = theano.function([x, i1, i2, i3, i4, v], z, mode=mode)
     prog = f.maker.fgraph.toposort()
     assert len(prog) != 1