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use crate::reactor::*;
macro_rules! impl_reactor_for_tuple {
( $($args:ident,)+ ) => {
/// Notifies all [`Reactor`]s in the tuple in order.
///
/// <small>Currently implemented for tuples of up to 12 elements.</small>
///
/// # Example
///
/// ```rust
/// use reducer::*;
/// use std::error::Error;
///
/// #[derive(Debug)]
/// struct State { /* ... */ }
/// struct Action { /* ... */ }
///
/// impl Reducer<Action> for State {
/// fn reduce(&mut self, action: Action) {
/// // ...
/// }
/// }
///
/// struct GUI { /* ... */ }
/// struct DebugLogger { /* ... */ }
///
/// impl Reactor<State> for GUI {
/// type Error = Box<dyn Error>;
/// fn react(&mut self, state: &State) -> Result<(), Self::Error> {
/// // ...
/// Ok(())
/// }
/// }
///
/// impl Reactor<State> for DebugLogger {
/// type Error = Box<dyn Error>;
/// fn react(&mut self, state: &State) -> Result<(), Self::Error> {
/// println!("[DEBUG] {:#?}", state);
/// Ok(())
/// }
/// }
///
/// let gui = GUI { /* ... */ };
/// let logger = DebugLogger { /* ... */ };
///
/// let mut store = Store::new(State { /* ... */ }, (gui, logger));
///
/// // Both `gui` and `logger` get notified of state changes.
/// store.dispatch(Action { /* ... */ });
/// ```
impl<S, X, $($args,)+> Reactor<S> for ($($args,)+)
where
S: ?Sized,
$($args: Reactor<S, Error = X>,)+
{
type Error = X;
fn react(&mut self, state: &S) -> Result<(), Self::Error> {
#[allow(non_snake_case)]
let ($($args,)+) = self;
$($args.react(state)?;)+
Ok(())
}
}
};
}
macro_rules! impl_reactor_for_tuples {
() => {};
( $head:ident $(, $tail:ident)* $(,)? ) => {
impl_reactor_for_tuples!($($tail,)*);
reverse!(impl_reactor_for_tuple!($head $(, $tail)*));
};
}
impl_reactor_for_tuples!(L, K, J, I, H, G, F, E, D, C, B, A);
#[cfg(test)]
mod tests {
use super::*;
use mockall::predicate::*;
use test_strategy::proptest;
macro_rules! test_reactor_for_tuples {
() => {};
( $head:ident $(, $tail:ident)* $(,)? ) => {
#[proptest]
fn $head(state: u8, results: [Result<(), u8>; count!($($tail,)*) + 1]) {
let (idx, result) = results
.iter()
.enumerate()
.find(|(_, r)| r.is_err())
.map_or((results.len(), Ok(())), |(i, &r)| (i, r));
let mut mocks: [MockReactor<_, _>; count!($($tail,)*) + 1] = Default::default();
for (i, (mock, &result)) in mocks.iter_mut().zip(&results).enumerate() {
mock.expect_react()
.with(eq(state))
.times(if i > idx { 0 } else { 1 })
.return_const(result);
}
let [$head, $($tail,)*] = mocks;
let mut reactor = ($head, $($tail,)*);
assert_eq!(Reactor::react(&mut reactor, &state), result);
}
test_reactor_for_tuples!($($tail,)*);
};
}
test_reactor_for_tuples!(_12, _11, _10, _09, _08, _07, _06, _05, _04, _03, _02, _01);
}