Fix test_time test and ensure coverage

One of the test_time methods did not actually assert the exception message it was trying to detect as the assertion statement was contained within the context manager handling the exception. I've moved it out of the context so it actually runs.

I've also added a few `praga: no cover` comments for parts that were artifically lowering coverage of the test suite.

3 files changed, 4 insertions, 4 deletions

diff --git a/tests/bot/cogs/test_duck_pond.py b/tests/bot/cogs/test_duck_pond.py
index e164f7544..7370b8471 100644
--- a/tests/bot/cogs/test_duck_pond.py
+++ b/tests/bot/cogs/test_duck_pond.py
@@ -312,7 +312,7 @@ class DuckPondTests(base.LoggingTestsMixin, unittest.IsolatedAsyncioTestCase):
         self.cog.webhook = helpers.MockAsyncWebhook()
         log = logging.getLogger("bot.cogs.duck_pond")
 
-        for side_effect in side_effects:
+        for side_effect in side_effects:  # pragma: no cover
             send_attachments.side_effect = side_effect
             with patch(f"{MODULE_PATH}.DuckPond.send_webhook", new_callable=AsyncMock) as send_webhook:
                 with self.subTest(side_effect=type(side_effect).__name__):
diff --git a/tests/bot/rules/__init__.py b/tests/bot/rules/__init__.py
index 0233e7939..0d570f5a3 100644
--- a/tests/bot/rules/__init__.py
+++ b/tests/bot/rules/__init__.py
@@ -68,9 +68,9 @@ class RuleTest(unittest.IsolatedAsyncioTestCase, metaclass=ABCMeta):
     @abstractmethod
     def relevant_messages(self, case: DisallowedCase) -> Iterable[MockMessage]:
         """Give expected relevant messages for `case`."""
-        raise NotImplementedError
+        raise NotImplementedError  # pragma: no cover
 
     @abstractmethod
     def get_report(self, case: DisallowedCase) -> str:
         """Give expected error report for `case`."""
-        raise NotImplementedError
+        raise NotImplementedError  # pragma: no cover
diff --git a/tests/bot/utils/test_time.py b/tests/bot/utils/test_time.py
index de5724bca..694d3a40f 100644
--- a/tests/bot/utils/test_time.py
+++ b/tests/bot/utils/test_time.py
@@ -43,7 +43,7 @@ class TimeTests(unittest.TestCase):
         for max_units in test_cases:
             with self.subTest(max_units=max_units), self.assertRaises(ValueError) as error:
                 time.humanize_delta(relativedelta(days=2, hours=2), 'hours', max_units)
-                self.assertEqual(str(error), 'max_units must be positive')
+            self.assertEqual(str(error.exception), 'max_units must be positive')
 
     def test_parse_rfc1123(self):
         """Testing parse_rfc1123."""