1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93

use crate::reactor::*;

/// Notifies all [`Reactor`]s in the slice in order.
///
/// # Example
///
/// ```rust
/// use reducer::*;
///
/// struct State { /* ... */ }
/// struct Action { /* ... */ }
///
/// impl Reducer<Action> for State {
///     fn reduce(&mut self, action: Action) {
///         // ...
///     }
/// }
///
/// struct Actor { /* ... */ }
/// struct ActorError(/*...*/);
///
/// impl Reactor<State> for Actor {
///     type Error = ActorError;
///     fn react(&mut self, state: &State) -> Result<(), Self::Error> {
///         // ...
///         Ok(())
///     }
/// }
///
/// # #[cfg(feature = "alloc")] {
/// let mut actors = vec![];
///
/// actors.push(Actor { /* ... */ });
/// actors.push(Actor { /* ... */ });
/// // ...
/// actors.push(Actor { /* ... */ });
///
/// let mut store = Store::new(State { /* ... */ }, actors.into_boxed_slice());
///
/// // All actors get notified of state changes.
/// store.dispatch(Action { /* ... */ });
/// # }
/// ```
impl<S, T> Reactor<S> for [T]
where
    S: ?Sized,
    T: Reactor<S>,
{
    type Error = T::Error;

    fn react(&mut self, state: &S) -> Result<(), Self::Error> {
        for reducer in self {
            reducer.react(state)?;
        }

        Ok(())
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use mockall::predicate::*;
    use std::vec::Vec;
    use test_strategy::proptest;

    #[proptest]
    fn react(state: u8, results: Vec<Result<(), u8>>) {
        let (idx, result) = results
            .iter()
            .enumerate()
            .find(|(_, r)| r.is_err())
            .map_or((results.len(), Ok(())), |(i, &r)| (i, r));

        let mut mocks: Vec<_> = results
            .into_iter()
            .enumerate()
            .map(move |(i, r)| {
                let mut mock = MockReactor::new();

                mock.expect_react()
                    .with(eq(state))
                    .times(if i > idx { 0 } else { 1 })
                    .return_const(r);

                mock
            })
            .collect();

        let reactor = mocks.as_mut_slice();
        assert_eq!(Reactor::react(reactor, &state), result);
    }
}