Update docstring and remove redundant attribute

I accidentally forgot to update the docstring of `CustomMockMixin`,
which changed quite dramatically in scope with the last commit. This
commit remedies that.

In addition, I inadvertently forgot to remove the `child_mock_type`
class attribute from `MockRole`. Since it uses the default value, it
is no longer necessary to specify it in the child class as well.

1 files changed, 9 insertions, 4 deletions

diff --git a/tests/helpers.py b/tests/helpers.py
index 673beae3f..8496ba031 100644
--- a/tests/helpers.py
+++ b/tests/helpers.py
@@ -50,7 +50,15 @@ class ColourMixin:
 
 
 class CustomMockMixin:
-    """Ensures attributes of our mock types will be instantiated with the correct mock type."""
+    """
+    Provides common functionality for our custom Mock types.
+
+    The cooperative `__init__` automatically creates `AsyncMock` attributes for every coroutine
+    function `inspect` detects in the `spec` instance we provide. In addition, this mixin takes care
+    of making sure child mocks are instantiated with the correct class. By default, the mock of the
+    children will be `unittest.mock.MagicMock`, but this can be overwritten by setting the attribute
+    `child_mock_type` on the custom mock inheriting from this mixin.
+    """
 
     child_mock_type = unittest.mock.MagicMock
 
@@ -179,9 +187,6 @@ class MockRole(CustomMockMixin, unittest.mock.Mock, ColourMixin, HashableMixin):
     Instances of this class will follow the specifications of `discord.Role` instances. For more
     information, see the `MockGuild` docstring.
     """
-
-    child_mock_type = unittest.mock.MagicMock
-
     def __init__(self, name: str = "role", role_id: int = 1, position: int = 1, **kwargs) -> None:
         super().__init__(spec=role_instance, **kwargs)