pdk-classy 1.9.1-alpha.2

PDK Classy
Documentation 
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// Copyright (c) 2026, Salesforce, Inc.,
// All rights reserved.
// For full license text, see the LICENSE.txt file

use std::{
    future::{ready, Future, Ready},
    ops::Deref,
};

use super::FromContext;
use crate::BoxError;

mod mode {
    pub enum Once {}

    pub enum Repeat {}
}

#[doc(hidden)]
pub struct Exclusive<'c, C> {
    context: &'c C,
}

impl<'c, C> Exclusive<'c, C> {
    pub(crate) fn new(context: &'c C) -> Self {
        Self { context }
    }

    pub fn get(&self) -> &'c C {
        self.context
    }
}

impl<C> Deref for Exclusive<'_, C> {
    type Target = C;

    fn deref(&self) -> &Self::Target {
        self.get()
    }
}

/// Extract data from the given context. The extraction will only be possible once.
pub trait FromContextOnce<C, M = mode::Once>: Sized {
    type Error: Into<BoxError>;

    type Future<'c>: Future<Output = Result<Self, Self::Error>> + 'c
    where
        C: 'c;

    fn from_context_once(context: Exclusive<C>) -> Self::Future<'_>;
}

impl<C, T> FromContextOnce<C, mode::Repeat> for T
where
    for<'c> T: FromContext<C> + 'c,
{
    type Error = T::Error;

    type Future<'c>
        = Ready<Result<Self, Self::Error>>
    where
        C: 'c,
        Self: 'c;

    fn from_context_once(context: Exclusive<C>) -> Self::Future<'_> {
        ready(T::from_context(&context))
    }
}