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

use futures::{pin_mut, Stream};
use pin_project::pin_project;
use serde::{Deserialize, Serialize};
use std::{
	pin::Pin, task::{Context, Poll}
};

use super::{
	DistributedPipe, DistributedStream, PipeTask, PipeTaskAsync, StreamTask, StreamTaskAsync
};
use crate::{
	pool::ProcessSend, sink::{Sink, SinkMap}
};

#[must_use]
pub struct Inspect<I, F> {
	i: I,
	f: F,
}
impl<I, F> Inspect<I, F> {
	pub(crate) fn new(i: I, f: F) -> Self {
		Self { i, f }
	}
}

impl<I: DistributedStream, F> DistributedStream for Inspect<I, F>
where
	F: FnMut(&I::Item) + Clone + ProcessSend,
{
	type Item = I::Item;
	type Task = InspectTask<I::Task, F>;

	fn size_hint(&self) -> (usize, Option<usize>) {
		self.i.size_hint()
	}
	fn next_task(&mut self) -> Option<Self::Task> {
		self.i.next_task().map(|task| {
			let f = self.f.clone();
			InspectTask { task, f }
		})
	}
}

impl<I: DistributedPipe<Source>, F, Source> DistributedPipe<Source> for Inspect<I, F>
where
	F: FnMut(&<I as DistributedPipe<Source>>::Item) + Clone + ProcessSend,
{
	type Item = I::Item;
	type Task = InspectTask<I::Task, F>;

	fn task(&self) -> Self::Task {
		let task = self.i.task();
		let f = self.f.clone();
		InspectTask { task, f }
	}
}

#[pin_project]
#[derive(Serialize, Deserialize)]
pub struct InspectTask<T, F> {
	#[pin]
	task: T,
	f: F,
}

impl<C: StreamTask, F> StreamTask for InspectTask<C, F>
where
	F: FnMut(&C::Item) + Clone,
{
	type Item = C::Item;
	type Async = InspectTask<C::Async, F>;
	fn into_async(self) -> Self::Async {
		InspectTask {
			task: self.task.into_async(),
			f: self.f,
		}
	}
}
impl<C: PipeTask<Source>, F, Source> PipeTask<Source> for InspectTask<C, F>
where
	F: FnMut(&C::Item) + Clone,
{
	type Item = C::Item;
	type Async = InspectTask<C::Async, F>;
	fn into_async(self) -> Self::Async {
		InspectTask {
			task: self.task.into_async(),
			f: self.f,
		}
	}
}

impl<C: StreamTaskAsync, F> StreamTaskAsync for InspectTask<C, F>
where
	F: FnMut(&C::Item) + Clone,
{
	type Item = C::Item;

	fn poll_run(
		self: Pin<&mut Self>, cx: &mut Context, sink: Pin<&mut impl Sink<Self::Item>>,
	) -> Poll<()> {
		let mut self_ = self.project();
		let (task, f) = (self_.task, &mut self_.f);
		let sink = SinkMap::new(sink, |item| {
			f(&item);
			item
		});
		pin_mut!(sink);
		task.poll_run(cx, sink)
	}
}

impl<C: PipeTaskAsync<Source>, F, Source> PipeTaskAsync<Source> for InspectTask<C, F>
where
	F: FnMut(&<C as PipeTaskAsync<Source>>::Item) + Clone,
{
	type Item = C::Item;

	fn poll_run(
		self: Pin<&mut Self>, cx: &mut Context, stream: Pin<&mut impl Stream<Item = Source>>,
		sink: Pin<&mut impl Sink<Self::Item>>,
	) -> Poll<()> {
		let mut self_ = self.project();
		let (task, f) = (self_.task, &mut self_.f);
		let sink = SinkMap::new(sink, |item| {
			f(&item);
			item
		});
		pin_mut!(sink);
		task.poll_run(cx, stream, sink)
	}
}