Added stricter controls over the returned values by the datasource.

Created by: stefanoborini

The datasource must return a list of DataValues. This PR enforces the types of both the returned entity and its content.

force_bdss/tests/test_core_evaluation_driver.py

@@ -88,7 +88,7 @@ class TestCoreEvaluationDriver(unittest.TestCase):
                     self,
                     RuntimeError,
                     "The run method of data source test_data_source must"
-                    " return a list. It returned instead <type 'str'>. Fix"
+                    " return a list. It returned instead <.* 'str'>. Fix"
                     " the run\(\) method to return the appropriate entity."):
                 driver.application_started()
 
@@ -104,7 +104,7 @@ class TestCoreEvaluationDriver(unittest.TestCase):
                     RuntimeError,
                     "The result list returned by DataSource test_data_source"
                     " contains an entry that is not a DataValue."
-                    " An entry of type <type 'str'> was instead found"
+                    " An entry of type <.* 'str'> was instead found"
                     " in position 0."
                     " Fix the DataSource.run\(\) method to"
                     " return the appropriate entity."