Mocking in Rust

[peter-lyons-kehl]

Thank you for blessed-rs Nico.

Suggest adding an entry on Mockall, with 3: links:

1. Comparison to other ways of mocking (in Rust) https://asomers.github.io/mock_shootout,
2. the crate itself: mockall https://docs.rs/mockall/latest/mockall, and
3. its sister crate mockall_double https://docs.rs/mockall_double/latest/mockall_double/index.html.

Suggest adding a new section "Mocking". Of course, up to you where to put it/what to call it. But, I don't think it fits under current Tooling > Testing, since it's not really a (shell) tool.

(I may have one more, separate, crate to add.)

[musjj]

There's also https://github.com/nrxus/faux, which is great for mocking structs with multiple impl blocks spread across modules.

#[faux::create]
pub struct MyStruct {}

#[faux::methods]
impl MyStruct {
    pub fn three(&self) -> i32 {
        3
    }
}

mod foo_inner {
    use super::MyStruct;

    #[faux::methods(path = "super")]
    impl MyStruct {
        pub fn four(&self) -> i32 {
            self.three() + 1
        }
    }
}

AFAIK, this is not possible with mockall.

[djc]

Would be good to get some recent download numbers in here for the different crates.