Add test that we can reraise and extend the error msg of BadOptimization

theano/compile/tests/test_debugmode.py

 from __future__ import absolute_import, print_function, division
-from nose.plugins.skip import SkipTest
+import sys
 import unittest
 
+from nose.plugins.skip import SkipTest
+from nose.tools import assert_raises
 import numpy as np
+from six import reraise
 
 from theano import config
 from theano import gof
+from theano.gof.link import raise_with_op
 import theano
-import theano.tensor
 from theano.compat import exc_message
 from theano.compile import debugmode
-import theano.compile
+import theano.tensor
 from theano.tests import unittest_tools as utt
 
 
@@ -255,23 +258,54 @@ def test_badoptimization_opt_err():
                                                         inputs[-1]))
                 return [node.op(*inputs)]
         return False
+    @gof.local_optimizer([theano.tensor.add])
+    def insert_bad_dtype(node):
+        if node.op == theano.tensor.add:
+            inputs = list(node.inputs)
+            if inputs[-1].owner is None:
+
+                return [node.outputs[0].astype('float32')]
+        return False
     edb = gof.EquilibriumDB()
     edb.register('insert_bigger_b_add', insert_bigger_b_add, 'all')
     opt = edb.query('+all')
+    edb2 = gof.EquilibriumDB()
+    edb2.register('insert_bad_dtype', insert_bad_dtype, 'all')
+    opt2 = edb2.query('+all')
 
     a = theano.tensor.dvector()
     b = theano.tensor.dvector()
 
     f = theano.function([a, b], a + b,
                         mode=debugmode.DebugMode(optimizer=opt))
-
     try:
         f([1.0, 2.0, 3.0], [2, 3, 4],)
-    except Exception as e:
+    except ValueError as e:
         assert 'insert_bigger_b_add' in exc_message(e)
-        return  # TEST PASS
+    else:
+        assert False
 
-    assert False
+    # Test that opt that do an illegal change still get the error from gof.
+    try:
+        with theano.configparser.change_flags(on_opt_error='raise'):
+            f2 = theano.function([a, b], a + b,
+                                 mode=debugmode.DebugMode(optimizer=opt2,
+                                                          stability_patience=1))
+        f2([1.0, 2.0, 3.0], [2, 3, 4],)
+    except theano.gof.toolbox.BadOptimization as e:
+        assert 'insert_bad_dtype' in str(e)
+        # Test that we can reraise the error with an extended message
+        try:
+            new_e = e.__class__("TTT"+str(e))
+            exc_type, exc_value, exc_trace = sys.exc_info()
+            exc_value = new_e
+            reraise(e.__class__, exc_value, exc_trace)
+        except theano.gof.toolbox.BadOptimization as e:
+            pass
+        else:
+            assert False
+    else:
+        assert False
 
 
 def test_stochasticoptimization():