$ mockall_

Crate

Name: mockall New version: 0.14.0 Release date: 2025-11-22T17:52:07.546670Z

Crate readme

Short description A powerful mock object library for Rust.

Long description Mockall is a mock object library for unit testing in Rust, allowing controlled responses from mock objects that share interfaces with real objects. It is written in 100% safe and stable Rust, compatible with Rust 1.77.0 and higher. It simplifies testing by enabling the creation of mocks without involving the real implementations, thereby facilitating the testing of edge and error cases easily.

Features • Cargo feature flags • 100% safe and stable Rust • Compatible with Rust 1.77.0 and higher

Code Examples Add to Cargo.toml

 [dev-dependencies]
mockall = "0.14.0"

Basic usage

 #[cfg(test)]
use mockall::{automock, mock, predicate::*};
#[cfg_attr(test, automock)]
trait MyTrait {
    fn foo(&self, x: u32) -> u32;
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn mytest() {
        let mut mock = MockMyTrait::new();
        mock.expect_foo()
            .with(eq(4))
            .times(1)
            .returning(|x| x + 1);
        assert_eq!(5, mock.foo(4));
    }
}

Links • https://crates.io/crates/mockall • https://docs.rs/mockall

https://docs.rs/mockall

Release info

Release version: N/A

Release description N/A

Code Examples N/A