Modified test_opt.py to use check_stack_trace and modified check_stack_trace to…

Modified test_opt.py to use check_stack_trace and modified check_stack_trace to loop over outputs for ops_to_check=last and some refactoring

Modified test_opt.py to use check_stack_trace and modified check_stack_trace to…
b6b797d7 · Samira Ebrahimi Kahou · e3569d12 · b6b797d7 · b6b797d7
--- a/theano/gof/opt.py
+++ b/theano/gof/opt.py
@@ -2667,7 +2667,7 @@ def check_stack_trace(f_or_fgraph, ops_to_check='last', bug_print='raise'):
    # if ops_to_check is a string
    if isinstance(ops_to_check, string_types):
        if ops_to_check == 'last':
-            apply_nodes_to_check = [fgraph.outputs[0].owner]
+            apply_nodes_to_check = [fgraph.outputs[i].owner for i in range(len(fgraph.outputs))]
        elif ops_to_check == 'all':
            apply_nodes_to_check = fgraph.apply_nodes
        else:

--- a/theano/tensor/tests/test_opt.py
+++ b/theano/tensor/tests/test_opt.py