Turn enable_deprecations_as_exceptions on in conftest.py
@@ -22,7 +22,8 @@ packagename = os.path.basename(os.path.dirname(__file__))
TESTED_VERSIONS[packagename] = version.version
# Treat all DeprecationWarnings as exceptions
-# enable_deprecations_as_exceptions()
+from astropy.tests.helper import enable_deprecations_as_exceptions
+enable_deprecations_as_exceptions()
# Declare for which packages version numbers should be displayed
# when running the tests
