Implement connection_pattern

theano/tests/breakpoint.py

@@ -93,8 +93,19 @@ class PdbBreakpoint(Op):
             output_storage[i][0] = monitored[i]
 
     def grad(self, inputs, output_gradients):
-        return ([DisconnectedType()] + output_gradients)
+        return ([DisconnectedType()()] + output_gradients)
 
     def infer_shape(self, inputs, input_shapes):
         # Return the shape of every input but the condition (first input)
         return input_shapes[1:]
+
+    def connection_pattern(self, node):
+
+        nb_inp = len(node.inputs)
+        nb_out = nb_inp - 1
+
+        # First input is connected to no output and every other input n is
+        # connected to input n-1
+        connections = [[out_idx == inp_idx - 1 for out_idx in range(nb_out)]
+                       for inp_idx in range(nb_inp)]
+        return connections