asserting/option/
mod.rs

1//! Implementation of assertions for `Option` values.
2
3use crate::assertions::{AssertHasValue, AssertOption, AssertOptionValue};
4use crate::expectations::{HasValue, IsNone, IsSome};
5use crate::spec::{Expectation, Expression, FailingStrategy, Spec, Unknown};
6use crate::std::fmt::Debug;
7#[cfg(not(feature = "std"))]
8use alloc::{format, string::String};
9
10impl<S, R> AssertOption for Spec<'_, Option<S>, R>
11where
12    S: Debug,
13    R: FailingStrategy,
14{
15    fn is_some(self) -> Self {
16        self.expecting(IsSome)
17    }
18
19    fn is_none(self) -> Self {
20        self.expecting(IsNone)
21    }
22}
23
24impl<'a, T, R> AssertOptionValue<'a, T, R> for Spec<'a, Option<T>, R>
25where
26    R: FailingStrategy,
27{
28    fn some(self) -> Spec<'a, T, R> {
29        self.mapping(|subject| match subject {
30            None => {
31                panic!("assertion failed: expected the subject to be `Some(_)`, but was `None`")
32            },
33            Some(value) => value,
34        })
35    }
36}
37
38impl<S, E, R> AssertHasValue<E> for Spec<'_, Option<S>, R>
39where
40    S: PartialEq<E> + Debug,
41    E: Debug,
42    R: FailingStrategy,
43{
44    fn has_value(self, expected: E) -> Self {
45        self.expecting(HasValue { expected })
46    }
47}
48
49impl<T> Expectation<Option<T>> for IsSome
50where
51    T: Debug,
52{
53    fn test(&mut self, subject: &Option<T>) -> bool {
54        subject.is_some()
55    }
56
57    fn message(&self, expression: Expression<'_>, actual: &Option<T>) -> String {
58        format!(
59            "expected {expression} is {:?}\n   but was: {actual:?}\n  expected: {:?}",
60            Some(Unknown),
61            Some(Unknown)
62        )
63    }
64}
65
66impl<T> Expectation<Option<T>> for IsNone
67where
68    T: Debug,
69{
70    fn test(&mut self, subject: &Option<T>) -> bool {
71        subject.is_none()
72    }
73
74    fn message(&self, expression: Expression<'_>, actual: &Option<T>) -> String {
75        format!(
76            "expected {expression} is {:?}\n   but was: {actual:?}\n  expected: {:?}",
77            None::<Unknown>, None::<Unknown>
78        )
79    }
80}
81
82impl<T, E> Expectation<Option<T>> for HasValue<E>
83where
84    T: PartialEq<E> + Debug,
85    E: Debug,
86{
87    fn test(&mut self, subject: &Option<T>) -> bool {
88        subject
89            .as_ref()
90            .is_some_and(|value| value == &self.expected)
91    }
92
93    fn message(&self, expression: Expression<'_>, actual: &Option<T>) -> String {
94        format!("expected {expression} is some containing {:?}\n   but was: {actual:?}\n  expected: {:?}",
95            &self.expected,
96            Some(&self.expected),
97        )
98    }
99}
100
101#[cfg(test)]
102mod tests;
asserting/option/mod.rs

asserting/option/
mod.rs
