mithril_common/test_utils/
mock_extensions.rs

1//! A set of tools for working with `automock`
2//!
3//! IMPORTANT: To avoid polluting production code, those tools do not expose or reexpose any
4//! `automock`types, users need to add them themselves to their crates.
5use std::sync::Arc;
6
7/// Helper to create configured Mockall mock.
8///
9/// This allows creation of the mock in a dedicated block isolated from the remaining test method
10/// code.
11pub struct MockBuilder<M: Default> {
12    phantom: std::marker::PhantomData<M>,
13}
14
15impl<M: Default> MockBuilder<M> {
16    /// Create a new instance of the mock with the given configuration
17    ///
18    /// The type must be specified either:
19    /// ```
20    /// use mithril_common::test_utils::mock_extensions::MockBuilder;
21    /// # #[derive(Default)] struct MockType {};
22    ///
23    /// // from the builder generic
24    /// let mock = MockBuilder::<MockType>::configure(|mock| {});
25    ///
26    /// // or from the closure parameter
27    /// let mock = MockBuilder::configure(|mock: &mut MockType| {});
28    /// ```
29    pub fn configure(mock_config: impl FnOnce(&mut M)) -> Arc<M> {
30        let mut mock = M::default();
31        mock_config(&mut mock);
32        Arc::new(mock)
33    }
34}
35
36#[cfg(test)]
37mod tests {
38    use super::*;
39
40    #[mockall::automock]
41    trait TestTrait {
42        fn test_method(&self) -> String;
43    }
44
45    #[test]
46    fn using_mock_builder() {
47        // specify the type on the closure parameter
48        let mock = MockBuilder::configure(|mock: &mut MockTestTrait| {
49            mock.expect_test_method()
50                .returning(|| "test explicit type".to_string());
51        });
52        assert_eq!("test explicit type".to_string(), mock.test_method());
53
54        // specify the type on the builder generic
55        let mock = MockBuilder::<MockTestTrait>::configure(|mock| {
56            mock.expect_test_method().returning(|| "test turbofish".to_string());
57        });
58        assert_eq!("test turbofish".to_string(), mock.test_method());
59    }
60}
mithril_common/test_utils/mock_extensions.rs

mithril_common/test_utils/
mock_extensions.rs
