Ensure views added to Client.add_view are persistent views

discord/client.py

@@ -1451,9 +1451,15 @@ class Client:
         -------
         TypeError
             A view was not passed.
+        ValueError
+            The view is not persistent. A persistent view has no timeout
+            and all their components have an explicitly provided custom_id.
         """
 
         if not isinstance(view, View):
             raise TypeError(f'expected an instance of View not {view.__class__!r}')
 
+        if not view.is_persistent():
+            raise ValueError('View is not persistent. Items need to have a custom_id set and View must have no timeout')
+
         self._connection.store_view(view, message_id)

discord/ui/button.py

@@ -98,6 +98,7 @@ class Button(Item[V]):
         if custom_id is not None and url is not None:
             raise TypeError('cannot mix both url and custom_id with Button')
 
+        self._provided_custom_id = custom_id is not None
         if url is None and custom_id is None:
             custom_id = os.urandom(16).hex()
 

discord/ui/item.py

@@ -56,6 +56,13 @@ class Item(Generic[V]):
         self._view: Optional[V] = None
         self._row: Optional[int] = None
         self._rendered_row: Optional[int] = None
+        # This works mostly well but there is a gotcha with
+        # the interaction with from_component, since that technically provides
+        # a custom_id most dispatchable items would get this set to True even though
+        # it might not be provided by the library user. However, this edge case doesn't
+        # actually affect the intended purpose of this check because from_component is
+        # only called upon edit and we're mainly interested during initial creation time.
+        self._provided_custom_id: bool = False
 
     def to_component_dict(self) -> Dict[str, Any]:
         raise NotImplementedError
@@ -77,6 +84,9 @@ class Item(Generic[V]):
     def is_dispatchable(self) -> bool:
         return False
 
+    def is_persistent(self) -> bool:
+        return self._provided_custom_id
+
     def __repr__(self) -> str:
         attrs = ' '.join(f'{key}={getattr(self, key)!r}' for key in self.__item_repr_attributes__)
         return f'<{self.__class__.__name__} {attrs}>'

discord/ui/select.py

@@ -101,6 +101,7 @@ class Select(Item[V]):
         row: Optional[int] = None,
     ) -> None:
         self._selected_values: List[str] = []
+        self._provided_custom_id = custom_id is not MISSING
         custom_id = os.urandom(16).hex() if custom_id is MISSING else custom_id
         options = [] if options is MISSING else options
         self._underlying = SelectMenu._raw_construct(

discord/ui/view.py

@@ -339,6 +339,14 @@ class View:
         """:class:`bool`: Whether the view has finished interacting."""
         return self._stopped.done()
 
+    def is_persistent(self) -> bool:
+        """:class:`bool`: Whether the view is set up as persistent.
+
+        A persistent view has all their components with a set ``custom_id`` and
+        a :attr:`timeout` set to ``None``.
+        """
+        return self.timeout is None and all(item.is_persistent() for item in self.children)
+
     async def wait(self) -> bool:
         """Waits until the view has finished interacting.