Flask plugin does not gracefully fail when view is None

I cannot use spec.path without providing view.

In flask.py:

def path_helper(
        self,
        path: Optional[str] = None,
        operations: Optional[dict] = None,
        parameters: Optional[List[dict]] = None,
        *,
        view: Optional[Union[Callable[..., Any], "RouteCallable"]] = None,
        app: Optional[Flask] = None,
        **kwargs: Any,
    ) -> Optional[str]:
        """Path helper that allows passing a Flask view function."""
        assert view is not None

The assert statement completely fails, this means that if someone was to define multiple plugins for apispec, then because this one fails any time view is not defined, there is no way forward.

Inside core.py inside the apispec, library, they handle any PluginMethodNotImplementedErrors, and move on. I would suggest raising that exception instead.

for plugin in self.plugins:
            try:
                ret = plugin.path_helper(
                    path=path, operations=operations, parameters=parameters, **kwargs
                )
            except PluginMethodNotImplementedError:
                continue

Start in flask.py at path_helper and compare its view=None behavior with the PluginMethodNotImplementedError handling shown in core.py. Verify the multi-plugin path-helper flow and confirm that a missing view lets later plugins run without triggering the assertion. Done means the Flask plugin no longer blocks that flow when view is absent.