PLAT-1858 Better capture of deprecation warnings

cms/envs/test.py

@@ -21,7 +21,6 @@ sessions. Assumes structure:
 from .common import *
 import os
 from path import Path as path
-from warnings import filterwarnings, simplefilter
 from uuid import uuid4
 from util.db import NoOpMigrationModules
 from openedx.core.lib.derived import derive_settings
@@ -175,15 +174,6 @@ CACHES = {
     },
 }
 
-# hide ratelimit warnings while running tests
-filterwarnings('ignore', message='No request passed to the backend, unable to rate-limit')
-
-# Ignore deprecation warnings (so we don't clutter Jenkins builds/production)
-# https://docs.python.org/2/library/warnings.html#the-warnings-filter
-# Change to "default" to see the first instance of each hit
-# or "error" to convert all into errors
-simplefilter('ignore')
-
 ################################# CELERY ######################################
 
 CELERY_ALWAYS_EAGER = True

cms/pytest.ini

@@ -1,6 +1,11 @@
 [pytest]
 DJANGO_SETTINGS_MODULE = cms.envs.test
 addopts = --nomigrations --reuse-db --durations=20 -p no:randomly
+# Enable default handling for all warnings, including those that are ignored by default;
+# but hide rate-limit warnings, because we deliberately don't throttle test user logins
+filterwarnings =
+    default
+    ignore:No request passed to the backend, unable to rate-limit.*:UserWarning
 norecursedirs = envs
 python_classes =
 python_files = tests.py test_*.py *_tests.py