pyright cannot use rx.event.EventSpec in a type definition

[masenf]

Describe the bug
error: Variable not allowed in type expression (reportInvalidTypeForm)

To Reproduce

import reflex as rx
from reflex.event import EventSpec


class State(rx.State):
    @rx.event
    def bad_toast(self) -> rx.event.EventSpec | None:
        return rx.toast.error("🥨!")

    @rx.event
    def good_toast(self) -> EventSpec | None:
        return rx.toast.success("🍞!")


def index() -> rx.Component:
    return rx.button("Toast 🥂", on_click=[State.good_toast, State.bad_toast])


app = rx.App()
app.add_page(index)

masenf@minicone repro-type-variable % pyright repro_type_variable/repro_type_variable.py
/Users/masenf/code/reflex-dev/repro-type-variable/repro_type_variable/repro_type_variable.py
  /Users/masenf/code/reflex-dev/repro-type-variable/repro_type_variable/repro_type_variable.py:7:28 - error: Variable not allowed in type expression (reportInvalidTypeForm)
1 error, 0 warnings, 0 informations

Expected behavior
Anything that needs to be used in a type expression must be defined statically at module level, NOT in a namespace like rx.event. We need to find another way to allow access to these types, like EventSpec, EventHandler, etc, without going through the EventNamespace

class EventNamespace(types.SimpleNamespace):
    """A namespace for event related classes."""

    Event = Event
    EventHandler = EventHandler
    EventSpec = EventSpec
    CallableEventSpec = CallableEventSpec
    EventChain = EventChain
    EventVar = EventVar
    LiteralEventVar = LiteralEventVar
    EventChainVar = EventChainVar
    LiteralEventChainVar = LiteralEventChainVar
    EventType = EventType
    EventCallback = EventCallback

☝️ this doesn't work with pyright.

There might be a way to hack this with a .pyi file, haven't tried. Although maybe it's better to just doc and move on?

Specifics (please complete the following information):

• Python Version: 3.11
• Reflex Version: 0.6.5a
• OS: macos

[linear]

ENG-4095 pyright cannot use `rx.event.EventSpec` in a type definition

[benedikt-bartscher]

We've had this issue in some of our repos and just imported EventSpec like this to mitigate it:

from reflex.event import EventSpec