diff --git a/pytest.ini b/pytest.ini
index 8d3bc91a5..f034bf233 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -2,4 +2,4 @@
 [pytest]
 usefixtures = chdir setlog
 python_files=test_*.py __init__.py
-addopts = --doctest-modules
+addopts = --doctest-modules --assert=plain