dnet-utils 0.1.1

Utilities for dnet
Documentation 
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
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152

//! Transport sending messages into the void, never receiving any messages.

use std::{
    convert::Infallible,
    marker::PhantomData,
    pin::Pin,
    task::{Context, Poll},
};

use futures::{stream::FusedStream, Sink, Stream};

/// Transport sending messages into the void, never receiving any messages.
///
/// Sending messages into this transport will always succeed.<br>
/// Attempt to receive message will never complete.
pub struct Void<Incoming, Outgoing> {
    #[cfg(feature = "logging")]
    logger: dnet_base::Logger,

    _incoming: PhantomData<Incoming>,
    _outgoing: PhantomData<Outgoing>,
}

impl<Incoming, Outgoing> Default for Void<Incoming, Outgoing> {
    fn default() -> Self {
        Self {
            #[cfg(feature = "logging")]
            logger: dnet_base::Logger::new::<Self>(),

            _incoming: PhantomData,
            _outgoing: PhantomData,
        }
    }
}

impl<Incoming, Outgoing> Sink<Outgoing> for Void<Incoming, Outgoing> {
    type Error = dnet_base::Error<Infallible>;

    fn poll_ready(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        let result = Poll::Ready(Ok(()));

        #[cfg(feature = "logging")]
        self.logger.log_ready(&result);

        result
    }

    fn start_send(self: Pin<&mut Self>, _item: Outgoing) -> Result<(), Self::Error> {
        let result = Ok(());

        #[cfg(feature = "logging")]
        self.logger.log_sending::<Outgoing, _>(&result, None);

        result
    }

    fn poll_flush(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        let result = Poll::Ready(Ok(()));

        #[cfg(feature = "logging")]
        self.logger.log_flush(&result);

        result
    }

    fn poll_close(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        let result = Poll::Ready(Ok(()));

        #[cfg(feature = "logging")]
        self.logger.log_close(&result);

        result
    }
}

impl<Incoming, Outgoing> Stream for Void<Incoming, Outgoing> {
    type Item = Result<Incoming, Infallible>;

    fn poll_next(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
        #[cfg(feature = "logging")]
        self.logger.log_receive_from_void();

        Poll::Pending
    }
}

impl<Incoming, Outgoing> FusedStream for Void<Incoming, Outgoing> {
    fn is_terminated(&self) -> bool {
        false
    }
}

#[cfg(feature = "logging")]
impl<Incoming, Outgoing> dnet_base::Logging for Void<Incoming, Outgoing> {
    const KIND: &'static str = "Void";

    fn with_logger<F, R>(&self, f: F) -> R
    where
        F: FnOnce(&dnet_base::Logger) -> R,
    {
        f(&self.logger)
    }

    fn with_logger_mut<'a, F, R>(&mut self, f: F) -> R
    where
        F: FnOnce(&mut dnet_base::Logger) -> R,
    {
        f(&mut self.logger)
    }
}

#[cfg(test)]
mod tests {
    use core::panic;
    use std::pin::pin;
    use std::time::Duration;

    use dnet_base::Receive;
    use dnet_tests::{dtest, dtest_configure};
    use dportable::time::sleep;
    use futures::{select, FutureExt, SinkExt};

    use crate::void::Void;

    dtest_configure!();

    #[dtest]
    async fn test_void() {
        let mut void: Void<i32, &str> = Void::default();

        #[cfg(feature = "logging")]
        {
            use dnet_base::Logging;
            dnet_tests::init_subscriber();
            void.enable_logging();
        }

        void.send("Hello").await.unwrap();

        let mut delay = pin!(sleep(Duration::from_millis(10)).fuse());
        let delay_finished_first;
        select! {
            _ = delay => {
                delay_finished_first = true;
            }
            _result = void.receive() => {
                panic!("received message");
            }
        }
        assert!(delay_finished_first);
    }
}