Bump mypy to 0.800 and fix issues (#451)

dev-requirements.txt

@@ -28,7 +28,7 @@ sphobjinv==2.0.1
 # TYPE CHECKING #
 #################
 
-mypy==0.790
+mypy==0.800
 
 #######################
 # DEPENDENCY CHECKING #

hikari/config.py

@@ -254,7 +254,7 @@ class HTTPTimeoutSettings:
     def _(self, attrib: attr.Attribute[typing.Optional[float]], value: typing.Optional[float]) -> None:
         # This error won't occur until some time in the future where it will be annoying to
         # try and determine the root cause, so validate it NOW.
-        if value is not None and (not isinstance(value, (float, int)) or value <= 0):  # type: ignore[unreachable]
+        if value is not None and (not isinstance(value, (float, int)) or value <= 0):
             raise ValueError(f"HTTPTimeoutSettings.{attrib.name} must be None, or a POSITIVE float/int")
 
 
@@ -325,7 +325,7 @@ class HTTPSettings:
     def _(self, _: attr.Attribute[typing.Optional[int]], value: typing.Optional[int]) -> None:
         # This error won't occur until some time in the future where it will be annoying to
         # try and determine the root cause, so validate it NOW.
-        if value is not None and (not isinstance(value, int) or value <= 0):  # type: ignore[unreachable]
+        if value is not None and (not isinstance(value, int) or value <= 0):
             raise ValueError("http_settings.max_redirects must be None or a POSITIVE integer")
 
     _ssl: typing.Union[bool, ssl_.SSLContext] = attr.ib(

hikari/impl/cache.py

@@ -1411,10 +1411,10 @@ def _garbage_collect_message(
             if guild_record:
                 self._garbage_collect_member(guild_record, message.object.member, decrement=1)
 
-        if message.object.referenced_message and message.object.referenced_message is not undefined.UNDEFINED:
+        if message.object.referenced_message:
             self._garbage_collect_message(message.object.referenced_message, decrement=1)
 
-        if message.object.mentions.users and message.object.mentions.users is not undefined.UNDEFINED:
+        if message.object.mentions.users:
             for user in message.object.mentions.users.values():
                 self._garbage_collect_user(user, decrement=1)
 
@@ -1489,7 +1489,7 @@ def _set_message(
             mention_users = {user_id: self._set_user(user) for user_id, user in message.mentions.users.items()}
 
         referenced_message: typing.Optional[cache_utility.RefCell[cache_utility.MessageData]] = None
-        if message.referenced_message and message.referenced_message is not undefined.UNDEFINED:
+        if message.referenced_message:
             referenced_message = self._set_message(message.referenced_message)
 
         if message.id not in self._referenced_messages and message.id not in self._message_entries:

hikari/impl/entity_factory.py

@@ -879,8 +879,8 @@ def serialize_embed(  # noqa: C901
                 # of debugging. The case that there are `None` should be detected immediately by
                 # static type checkers, regardless.
 
-                name = str(field.name) if field.name is not None else None  # type: ignore[unreachable]
-                value = str(field.value) if field.value is not None else None  # type: ignore[unreachable]
+                name = str(field.name) if field.name is not None else None
+                value = str(field.value) if field.value is not None else None
 
                 if name is None:
                     raise TypeError(f"in embed.fields[{i}].name - cannot have `None`")

hikari/impl/rest.py

@@ -1012,9 +1012,8 @@ async def create_message(
             embed = content
             content = undefined.UNDEFINED
 
-        # os.PathLike is missing @runtime_checkable causing mypy to complain
         elif undefined.count(attachment, attachments) == 2 and isinstance(
-            content, (files.Resource, files.RAWISH_TYPES, os.PathLike)  # type: ignore[misc]
+            content, (files.Resource, files.RAWISH_TYPES, os.PathLike)
         ):
             # Syntatic sugar, common mistake to accidentally send an attachment
             # as the content, so lets detect this and fix it for the user. This
@@ -1414,9 +1413,8 @@ async def execute_webhook(
             embed = content
             content = undefined.UNDEFINED
 
-        # os.PathLike is missing @runtime_checkable causing mypy to complain
         elif undefined.count(attachment, attachments) == 2 and isinstance(
-            content, (files.Resource, files.RAWISH_TYPES, os.PathLike)  # type: ignore[misc]
+            content, (files.Resource, files.RAWISH_TYPES, os.PathLike)
         ):
             # Syntatic sugar, common mistake to accidentally send an attachment
             # as the content, so lets detect this and fix it for the user. This

hikari/internal/cache.py

@@ -754,11 +754,7 @@ def build_from_entity(
         if not member and message.member:
             member = RefCell(MemberData.build_from_entity(message.member))
 
-        if (
-            not referenced_message
-            and message.referenced_message
-            and message.referenced_message is not undefined.UNDEFINED
-        ):
+        if not referenced_message and message.referenced_message:
             referenced_message = RefCell(MessageData.build_from_entity(message.referenced_message))
 
         return cls(