Future-proof test runner

tests/test_dataset.py

@@ -467,4 +467,5 @@ def tearDown(self):
 
 
 if __name__ == "__main__":
-    unittest.main()
+    from utils import FutureProofTestRunner
+    unittest.main(testRunner=FutureProofTestRunner)

tests/test_plugins.py

@@ -2,6 +2,9 @@
 import unittest
 from pathlib import Path
 from tempfile import gettempdir
+from contextlib import redirect_stdout
+import io
+
 
 from iris import AbstractRawDataset, DiffractionDataset
 from iris.plugins import load_plugin
@@ -45,8 +48,11 @@ def test_reduction(self):
 class TestBrokenPlugin(unittest.TestCase):
     def test_loading_broken_plugin(self):
         """ Test that exceptions are caught when loading a broken plug-in. """
-        load_plugin(BROKEN_PLUGIN_PATH)
+        to_the_void = io.StringIO()
+        with redirect_stdout(to_the_void):
+            load_plugin(BROKEN_PLUGIN_PATH)
 
 
 if __name__ == "__main__":
-    unittest.main()
+    from utils import FutureProofTestRunner
+    unittest.main(testRunner=FutureProofTestRunner)

tests/test_raw.py

@@ -71,4 +71,5 @@ def test_init_metadata(self):
 
 
 if __name__ == "__main__":
-    unittest.main()
+    from utils import FutureProofTestRunner
+    unittest.main(testRunner=FutureProofTestRunner)

tests/utils.py

@@ -0,0 +1,13 @@
+"""
+Utility functions for tests
+"""
+import unittest
+import warnings
+
+class FutureProofTestRunner(unittest.TextTestRunner):
+    """
+    A test runner that raises errors on Deprecation warnings.
+    """
+    def run(self, *args, **kwargs):
+        warnings.filterwarnings("error", category=DeprecationWarning)
+        return super().run(*args, **kwargs)