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
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
#![cfg(feature="executor")]
use core::pin::Pin;
use std::convert::Infallible;
use futures::{
stream::{self, repeat, Repeat, StreamExt, TryStreamExt},
task::Poll,
Stream,
};
use futures_executor::block_on;
use futures_task::Context;
use futures_test::task::noop_context;
#[test]
fn try_filter_map_after_err() {
let cx = &mut noop_context();
let mut s = stream::iter(1..=3)
.map(Ok)
.try_filter_map(|v| async move { Err::<Option<()>, _>(v) })
.filter_map(|r| async move { r.ok() })
.boxed();
assert_eq!(Poll::Ready(None), s.poll_next_unpin(cx));
}
#[test]
fn try_skip_while_after_err() {
let cx = &mut noop_context();
let mut s = stream::iter(1..=3)
.map(Ok)
.try_skip_while(|_| async move { Err::<_, ()>(()) })
.filter_map(|r| async move { r.ok() })
.boxed();
assert_eq!(Poll::Ready(None), s.poll_next_unpin(cx));
}
#[test]
fn try_take_while_after_err() {
let cx = &mut noop_context();
let mut s = stream::iter(1..=3)
.map(Ok)
.try_take_while(|_| async move { Err::<_, ()>(()) })
.filter_map(|r| async move { r.ok() })
.boxed();
assert_eq!(Poll::Ready(None), s.poll_next_unpin(cx));
}
#[test]
fn try_flatten_unordered() {
let test_st = stream::iter(1..7)
.map(|val: u32| {
if val % 2 == 0 {
Ok(stream::unfold((val, 1), |(val, pow)| async move {
Some((val.pow(pow), (val, pow + 1)))
})
.take(3)
.map(move |val| if val % 16 != 0 { Ok(val) } else { Err(val) }))
} else {
Err(val)
}
})
.map_ok(Box::pin)
.try_flatten_unordered(None);
block_on(async move {
assert_eq!(
// All numbers can be divided by 16 and odds must be `Err`
// For all basic evens we must have powers from 1 to 3
vec![
Err(1),
Err(3),
Err(5),
Ok(2),
Ok(4),
Ok(6),
Ok(4),
Err(16),
Ok(36),
Ok(8),
Err(64),
Ok(216)
],
test_st.collect::<Vec<_>>().await
)
});
#[derive(Clone, Debug)]
struct ErrorStream {
error_after: usize,
polled: usize,
}
impl Stream for ErrorStream {
type Item = Result<Repeat<Result<(), ()>>, ()>;
fn poll_next(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Option<Self::Item>> {
if self.polled > self.error_after {
panic!("Polled after error");
} else {
let out =
if self.polled == self.error_after { Err(()) } else { Ok(repeat(Ok(()))) };
self.polled += 1;
Poll::Ready(Some(out))
}
}
}
block_on(async move {
let mut st = ErrorStream { error_after: 3, polled: 0 }.try_flatten_unordered(None);
let mut ctr = 0;
while (st.try_next().await).is_ok() {
ctr += 1;
}
assert_eq!(ctr, 0);
assert_eq!(
ErrorStream { error_after: 10, polled: 0 }
.try_flatten_unordered(None)
.inspect_ok(|_| panic!("Unexpected `Ok`"))
.try_collect::<Vec<_>>()
.await,
Err(())
);
let mut taken = 0;
assert_eq!(
ErrorStream { error_after: 10, polled: 0 }
.map_ok(|st| st.take(3))
.try_flatten_unordered(1)
.inspect(|_| taken += 1)
.try_fold((), |(), res| async move { Ok(res) })
.await,
Err(())
);
assert_eq!(taken, 31);
})
}
async fn is_even(number: u8) -> bool {
number % 2 == 0
}
#[test]
fn try_all() {
block_on(async {
let empty: [Result<u8, Infallible>; 0] = [];
let st = stream::iter(empty);
let all = st.try_all(is_even).await;
assert_eq!(Ok(true), all);
let st = stream::iter([Ok::<_, Infallible>(2), Ok(4), Ok(6), Ok(8)]);
let all = st.try_all(is_even).await;
assert_eq!(Ok(true), all);
let st = stream::iter([Ok::<_, Infallible>(2), Ok(3), Ok(4)]);
let all = st.try_all(is_even).await;
assert_eq!(Ok(false), all);
let st = stream::iter([Ok(2), Ok(4), Err("err"), Ok(8)]);
let all = st.try_all(is_even).await;
assert_eq!(Err("err"), all);
});
}
#[test]
fn try_any() {
block_on(async {
let empty: [Result<u8, Infallible>; 0] = [];
let st = stream::iter(empty);
let any = st.try_any(is_even).await;
assert_eq!(Ok(false), any);
let st = stream::iter([Ok::<_, Infallible>(1), Ok(2), Ok(3)]);
let any = st.try_any(is_even).await;
assert_eq!(Ok(true), any);
let st = stream::iter([Ok::<_, Infallible>(1), Ok(3), Ok(5)]);
let any = st.try_any(is_even).await;
assert_eq!(Ok(false), any);
let st = stream::iter([Ok(1), Ok(3), Err("err"), Ok(8)]);
let any = st.try_any(is_even).await;
assert_eq!(Err("err"), any);
});
}
|
