Example from testing docs has compile warning and does not pass

[Craig-Macomber]

Problem

Example test code from https://dioxuslabs.com/learn/0.6/cookbook/testing# has compile warning and does not pass

Steps To Reproduce

Steps to reproduce the behavior:

• Copy hook testing example from https://dioxuslabs.com/learn/0.6/cookbook/testing#hook-testing
• Compile the code.
• Run the test

Expected behavior

Example test compiles without warnings and passe

Actual Behavior

thread::Scope import is unused.

running 1 test
test test ... FAILED

successes:

successes:

failures:

---- test stdout ----

thread 'test' panicked at src/main.rs:24:17:
assertion left == right failed
left: 1
right: 4

Environment:

• Dioxus version: 6.3
• Rust version: 1.85.0
• OS info: linux
• App platform: desktop

Proposed solution

Remove the unused input, and fix the test. I'm not sure whats wrong with it: that example is complex enough that its not obvious to me.

I'd also recommend adding a simpler example for cases which don't require testing mutations. Something like:

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

    fn assert_rsx_eq(first: Element, second: Element) {
        let first = dioxus_ssr::render_element(first);
        let second = dioxus_ssr::render_element(second);
        pretty_assertions::assert_str_eq!(first, second);
    }

    fn test_hook_simple(mut check: impl FnMut() + 'static) {
        fn mock_app() -> Element {
            rsx! {
                div {}
            }
        }

        let vdom = VirtualDom::new(mock_app);

        vdom.in_runtime(|| {
            ScopeId::ROOT.in_runtime(|| {
                check();
            })
        })
    }

    #[test]
    fn example() {
        test_hook_simple(|| {
            // Example use of a hook which requires the Dioxus runtime to be present
            let signal = use_signal(|| "Hello".to_string());
            assert_rsx_eq(
                rsx! {
                    span {
                        {signal}
                        " world"
                    }
                },
                rsx! {
                    span { "Hello world" }
                },
            )
        });
    }
}

This examples uses a test utility I wrote and used for some actual testing in a real library, and proved quite useful.