assertr 0.5.6

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

use alloc::format;
use core::fmt::Display;

use crate::assertions::core::strip_quotation_marks;
use crate::{AssertThat, Mode, tracking::AssertionTracking};

#[allow(clippy::return_self_not_must_use)]
#[cfg_attr(feature = "fluent", assertr_derive::fluent_aliases)]
pub trait DisplayAssertions {
    fn has_display_value(self, expected: impl Display) -> Self;
}

impl<T: Display, M: Mode> DisplayAssertions for AssertThat<'_, T, M> {
    #[track_caller]
    fn has_display_value(self, expected: impl Display) -> Self {
        self.track_assertion();

        let actual_string = format!("{}", self.actual());
        let expected_string = format!("{expected}");

        let actual_str = strip_quotation_marks(actual_string.as_str());
        let expected_str = strip_quotation_marks(expected_string.as_str());

        if actual_str != expected_str {
            self.fail(format_args!(
                "Expected: {expected_str:?}\n\n  Actual: {actual_str:?}\n"
            ));
        }
        self
    }
}

#[cfg(test)]
mod tests {

    mod has_display_value {

        mod with_number {
            use crate::prelude::*;
            use indoc::formatdoc;

            #[test]
            fn succeeds_when_equal_using_same_value() {
                assert_that!(42).has_display_value(42);
            }

            #[test]
            fn succeeds_when_equal_using_string_representation() {
                assert_that!(42).has_display_value("42");
            }

            #[test]
            fn panics_when_not_equal() {
                assert_that_panic_by(|| {
                    assert_that!(42)
                        .with_location(false)
                        .has_display_value("foo")
                })
                .has_type::<String>()
                .is_equal_to(formatdoc! {r#"
                    -------- assertr --------
                    Expected: "foo"

                      Actual: "42"
                    -------- assertr --------
                "#});
            }
        }

        mod with_string {
            use crate::prelude::*;
            use indoc::formatdoc;

            #[test]
            fn succeeds_when_equal_using_string_representation() {
                assert_that!("foo:bar").has_display_value("foo:bar");
            }

            #[test]
            fn panics_when_not_equal() {
                assert_that_panic_by(|| {
                    assert_that!("foo:bar")
                        .with_location(false)
                        .has_display_value("foo:baz")
                })
                .has_type::<String>()
                .is_equal_to(formatdoc! {r#"
                    -------- assertr --------
                    Expected: "foo:baz"

                      Actual: "foo:bar"
                    -------- assertr --------
                "#});
            }
        }

        mod with_custom_struct {
            use std::fmt::Display;

            use crate::prelude::*;
            use indoc::formatdoc;

            #[allow(dead_code)] // Allow fields to never be read.
            struct Person {
                age: u32,
                alive: bool,
            }

            impl Display for Person {
                fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
                    f.write_fmt(format_args!(
                        "PERSON<AGE={},ALIVE={}>",
                        self.age, self.alive
                    ))
                }
            }

            #[test]
            fn succeeds_when_equal_using_string_representation() {
                assert_that!(Person {
                    age: 42,
                    alive: true,
                })
                .has_display_value("PERSON<AGE=42,ALIVE=true>");
            }

            #[test]
            fn panics_when_not_equal() {
                assert_that_panic_by(|| {
                    assert_that!(Person {
                        age: 42,
                        alive: true,
                    })
                    .with_location(false)
                    .has_display_value("foo")
                })
                .has_type::<String>()
                .is_equal_to(formatdoc! {r#"
                    -------- assertr --------
                    Expected: "foo"

                      Actual: "PERSON<AGE=42,ALIVE=true>"
                    -------- assertr --------
                "#});
            }
        }
    }
}