fix: add wutta.purge_email_settings() for cloning prod DB to test

tests/test_wutta.py

@@ -0,0 +1,26 @@
+# -*- coding: utf-8; -*-
+
+from unittest import TestCase
+from unittest.mock import MagicMock, patch, call
+
+from wuttamess import wutta as mod
+
+
+class TestPurgeEmailSettings(TestCase):
+
+    def test_basic(self):
+        c = MagicMock()
+        sql = MagicMock()
+        postgres = MagicMock(sql=sql)
+        with patch.object(mod, 'postgres', new=postgres):
+            mod.purge_email_settings(c, 'testy', appname='wuttatest')
+            sql.assert_has_calls([
+                call(c, "delete from setting where name like 'wuttatest.email.%.sender';",
+                     database='testy'),
+                call(c, "delete from setting where name like 'wuttatest.email.%.to';",
+                     database='testy'),
+                call(c, "delete from setting where name like 'wuttatest.email.%.cc';",
+                     database='testy'),
+                call(c, "delete from setting where name like 'wuttatest.email.%.bcc';",
+                     database='testy'),
+            ])