AppFlowy/frontend/rust-lib/lib-dispatch/src/util/ready.rs

use std::{
    future::Future,
    pin::Pin,
    task::{Context, Poll},
};

pub struct Ready<T> {
    val: Option<T>,
}

impl<T> Ready<T> {
    #[inline]
    pub fn into_inner(mut self) -> T {
        self.val.take().unwrap()
    }
}

impl<T> Unpin for Ready<T> {}

impl<T> Future for Ready<T> {
    type Output = T;

    #[inline]
    fn poll(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<T> {
        let val = self.val.take().expect("Ready polled after completion");
        Poll::Ready(val)
    }
}

pub fn ready<T>(val: T) -> Ready<T> {
    Ready { val: Some(val) }
}