Fix a test if vm.lazy=False, it expect it to be True.

theano/configparser.py

@@ -89,6 +89,37 @@ theano_raw_cfg = ConfigParser.RawConfigParser()
 theano_raw_cfg.read(config_files)
 
 
+def change_flags(**kwargs):
+    """
+    Use this as a decorator to change the value of Theano config variable.
+
+    Useful during tests.
+    """
+    def change_flags_exec(f):
+        def inner(*args, **kwargs_):
+            old_val = {}
+            for k in kwargs:
+                l = [v for v in theano.configparser._config_var_list
+                     if v.fullname == k]
+                assert len(l) == 1
+                old_val[k] = l[0].__get__()
+            try:
+                for k in kwargs:
+                    l = [v for v in theano.configparser._config_var_list
+                         if v.fullname == k]
+                    assert len(l) == 1
+                    l[0].__set__(None, kwargs[k])
+                return f(*args, **kwargs_)
+            finally:
+                for k in kwargs:
+                    l = [v for v in theano.configparser._config_var_list
+                         if v.fullname == k]
+                    assert len(l) == 1
+                    l[0].__set__(None, old_val[k])
+        return inner
+    return change_flags_exec
+
+
 def fetch_val_for_key(key):
     """Return the overriding config value for a key.
     A successful search returns a string value.

theano/sandbox/cuda/tests/test_memory.py

@@ -122,6 +122,7 @@ def test_memory():
         assert mem1 == freemem(), (mem1, freemem())
 
 
+@theano.configparser.change_flags(**{'vm.lazy': True})
 def test_memory_lazy():
     """As test_memory, but with the ifelse op.