assertr 0.5.3

Fluent assertions for the Rust programming language.
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
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

use crate::mode::Panic;
use crate::prelude::*;
use core::borrow::Borrow;
use core::fmt::Debug;
use std::ops::Deref;

/// Non-extracting assertions for the `tokio::sync::watch::Receiver` type.
/// These work in any mode (Panic or Capture).
#[allow(clippy::return_self_not_must_use)]
#[cfg_attr(feature = "fluent", assertr_derive::fluent_aliases)]
pub trait TokioWatchReceiverAssertions<T: Debug> {
    fn has_current_value(self, expected: impl Borrow<T>) -> Self
    where
        T: PartialEq;
}

impl<T: Debug, M: Mode> TokioWatchReceiverAssertions<T>
    for AssertThat<'_, tokio::sync::watch::Receiver<T>, M>
{
    #[track_caller]
    fn has_current_value(self, expected: impl Borrow<T>) -> Self
    where
        T: PartialEq,
    {
        self.derive(|it| it.borrow())
            .derive(Deref::deref)
            .is_equal_to(expected.borrow());
        self
    }
}

/// Assertions for tokio watch receivers that use data-extracting operations internally.
/// Only available in Panic mode.
#[allow(clippy::return_self_not_must_use)]
#[cfg_attr(feature = "fluent", assertr_derive::fluent_aliases)]
pub trait TokioWatchReceiverExtractAssertions<T: Debug> {
    fn has_changed(self) -> Self;

    fn has_not_changed(self) -> Self;
}

impl<T: Debug> TokioWatchReceiverExtractAssertions<T>
    for AssertThat<'_, tokio::sync::watch::Receiver<T>, Panic>
{
    fn has_changed(self) -> Self {
        self.derive(tokio::sync::watch::Receiver::has_changed)
            .with_detail_message("Expected a tokio `watch` channel to have changed.")
            .is_ok()
            .is_true();
        self
    }

    fn has_not_changed(self) -> Self {
        self.derive(tokio::sync::watch::Receiver::has_changed)
            .with_detail_message("Expected a tokio `watch` channel to have not changed.")
            .is_ok()
            .is_false();
        self
    }
}

#[cfg(test)]
mod tests {
    #[derive(Debug, PartialEq)]
    struct Person {
        name: String,
    }

    mod has_current_value {
        use super::Person;
        use crate::prelude::*;
        use indoc::formatdoc;

        #[tokio::test]
        async fn succeeds_when_equal() {
            let (tx, rx) = tokio::sync::watch::channel(Person { name: "bob".into() });
            tx.send(Person {
                name: "kevin".into(),
            })
            .unwrap();

            assert_that!(rx).has_current_value(Person {
                name: "kevin".into(),
            });
        }

        #[tokio::test]
        async fn panics_when_not_equal() {
            let (_tx, rx) = tokio::sync::watch::channel(Person { name: "bob".into() });

            assert_that_panic_by(|| {
                assert_that!(rx)
                    .with_location(false)
                    .has_current_value(Person {
                        name: "alice".into(),
                    })
            })
            .has_type::<String>()
            .is_equal_to(formatdoc! {r#"
                    -------- assertr --------
                    Expected: Person {{
                        name: "alice",
                    }}

                      Actual: Person {{
                        name: "bob",
                    }}
                    -------- assertr --------
                "#});
        }
    }

    mod has_changed {
        use super::Person;
        use crate::prelude::*;
        use indoc::formatdoc;

        #[tokio::test]
        async fn succeeds_when_changed() {
            let (_tx, mut rx) = tokio::sync::watch::channel(Person { name: "bob".into() });
            rx.mark_changed();

            assert_that!(rx).has_changed();
        }

        #[tokio::test]
        async fn panics_when_not_changed() {
            let (_tx, mut rx) = tokio::sync::watch::channel(Person { name: "bob".into() });
            rx.mark_unchanged();

            assert_that_panic_by(|| assert_that!(rx).with_location(false).has_changed())
                .has_type::<String>()
                .is_equal_to(formatdoc! {r#"
                    -------- assertr --------
                    Expected: true

                      Actual: false

                    Details: [
                        Expected a tokio `watch` channel to have changed.,
                    ]
                    -------- assertr --------
                "#});
        }
    }

    mod has_not_changed {
        use super::Person;
        use crate::prelude::*;
        use indoc::formatdoc;

        #[tokio::test]
        async fn succeeds_when_not_changed() {
            let (_tx, mut rx) = tokio::sync::watch::channel(Person { name: "bob".into() });
            rx.mark_unchanged();

            assert_that!(rx).has_not_changed();
        }

        #[tokio::test]
        async fn panics_when_changed() {
            let (_tx, mut rx) = tokio::sync::watch::channel(Person { name: "bob".into() });
            rx.mark_changed();

            assert_that_panic_by(|| assert_that!(rx).with_location(false).has_not_changed())
                .has_type::<String>()
                .is_equal_to(formatdoc! {r#"
                    -------- assertr --------
                    Expected: false

                      Actual: true

                    Details: [
                        Expected a tokio `watch` channel to have not changed.,
                    ]
                    -------- assertr --------
                "#});
        }
    }
}