[REF-2887] [Unconfirmed] Updating a field in an object in a collection of rx.Base models does not send delta

[masenf]

Describe the bug
On a call, a user reported an error where updating a field in an object in a collection from a background task, did not reflect the changes in the frontend until the collection was reassigned self.files = self.files.

I tried to reproduce this issue with a minimal example and was not successful, it worked as expected for me. More investigation is needed.

To Reproduce

import asyncio

import reflex as rx


class User(rx.Base):
    name: str
    status: int


class State(rx.State):
    users: list[User] = [
        User(name="Alice", status=1),
        User(name="Bob", status=1),
        User(name="Charlie", status=1),
    ]

    @rx.background
    async def munge_user(self):
        for user in self.users:
            if user.status == 1:
                break
        async with self:
            user.status = 2
        await asyncio.sleep(5)
        async with self:
            user.status = 3


def index() -> rx.Component:
    return rx.container(
        rx.color_mode.button(position="top-right"),
        rx.vstack(
            rx.table.root(
                rx.table.header(
                    rx.table.row(
                        rx.table.column_header_cell("Name"),
                        rx.table.column_header_cell("Status"),
                    ),
                ),
                rx.table.body(
                    rx.foreach(
                        State.users,
                        lambda user: rx.table.row(
                            rx.table.cell(user.name),
                            rx.table.cell(
                                rx.cond(user.status == 2, rx.spinner(), rx.text(user.status)),
                            ),
                        ),
                    ),
                ),
            ),
            rx.button("Munge User", on_click=State.munge_user),
            spacing="5",
            justify="center",
            min_height="85vh",
        ),
        rx.logo(),
    )


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

Expected behavior
Clicking the button should take the first user with status == 1, set it to 2, wait five seconds, then set it to 3. In the UI, if the user's status is 2, then it should show a loading spinner.

Specifics (please complete the following information):

• Python Version: 3.11.8
• Reflex Version: 0.5.1a3

_REF-2887

[bigdelys]

I am seeing a similar issue with reflex 0.5.2: whether I use a list of strings or a list of dictionaries, when I change the state variable from my background task, the change does not show up when using forEach, like:

    rx.foreach(
        AppState.chapter_bodies,
        lambda chapter_body, i: chapter(
            f"Chapter {i + 1}",
            chapter_body,
            AppState.chapter_instructions[i],
            i,
        ),
    ),