expectest/core/
result.rs

1use crate::core::SourceLocation;
2
3/// Represents result of unit testing.
4#[derive(Debug)]
5pub enum TestResult {
6    /// Denotes success.
7    Success,
8    /// Denotes failure.
9    Failure(Failure),
10}
11
12impl TestResult {
13    /// Creates a new instance of `TestResult` with a `Success` variant.
14    pub fn new_success() -> Self {
15        TestResult::Success
16    }
17
18    /// Creates a new instance of `TestResult` with a `Failure` variant using message
19    /// and location.
20    pub fn new_failure(message: String, location: Option<SourceLocation>) -> Self {
21        TestResult::Failure(Failure {
22            should_panic: true,
23            message: message,
24            location: location,
25        })
26    }
27
28    /// Asserts that `message` is equal to the failure message.
29    ///
30    /// Purpose of this method is the unit testing of failure messages. Convenient for
31    /// development.
32    ///
33    /// # Example
34    /// ```
35    /// # use expectest::prelude::*;
36    /// expect(0 == 1).to(be_true()).assert_eq_message("expected to be true");
37    /// ```
38    ///
39    /// # Panics
40    /// This method panics if the failure message is not equal to the `message`, or `self` is not
41    /// the `TestResult::Failure` variant.
42    pub fn assert_eq_message(self, message: &str) {
43        if let TestResult::Failure(mut failure) = self {
44            failure.should_panic = false;
45            assert_eq!(failure.message, message);
46        } else {
47            panic!("expected to be TestResult::Failure, got <{:?}>", self);
48        }
49    }
50}
51
52/// Represents data for `Failure` variant of a `TestResult`.
53///
54/// There is no public constructor for this struct. To create a new instance you should
55/// use `TestResult::new_failure` method.
56///
57/// This struct implements the `Drop` trait to print failure message and panic.
58#[derive(Debug)]
59pub struct Failure {
60    should_panic: bool,
61    message: String,
62    location: Option<SourceLocation>,
63}
64
65impl Failure {
66    #[cfg(feature = "nightly")]
67    fn panic(&self) {
68        use rust_core::panicking;
69
70        if let Some(location) = self.location {
71            let file_line = &(location.file, location.line, location.column);
72            panicking::panic_fmt(format_args!("{}", self.message), file_line);
73        } else {
74            panic!("assertion failed: `{}`", self.message);
75        }
76    }
77
78    #[cfg(not(feature = "nightly"))]
79    fn panic(&self) {
80        if let Some(location) = self.location {
81            panic!("assertion failed: `{}`, {}", self.message, location);
82        } else {
83            panic!("assertion failed: `{}`", self.message);
84        }
85    }
86}
87
88impl Drop for Failure {
89    fn drop(&mut self) {
90        if self.should_panic {
91            self.panic();
92        }
93    }
94}
95
96#[cfg(test)]
97mod tests {
98    use super::TestResult;
99
100    #[test]
101    #[should_panic]
102    fn it_panics() {
103        TestResult::new_failure("panics on drop".into(), None);
104    }
105}
expectest/core/result.rs

expectest/core/
result.rs
