[bug] assert_ipc_response (Rust tests for icp commands) are broken on 1.6.7

[ospfranco]

Hi, I'm trying to write tests for some of the Rust commands that are made available to JS. I was using the function provided by tauri::test::assert_ipc_response according to this SO answer:

fn create_app<R: tauri::Runtime>(mut builder: tauri::Builder<R>) -> tauri::App<R> {
    builder
        .setup(|app| {Ok(())})
        .invoke_handler(tauri::generate_handler![greet])
        .build(tauri::generate_context!())
        .expect("failed to build app")
}


#[cfg(test)]
mod tests {
    use tauri::Manager;
    #[test]
    fn something() {
        let data = r#"{"name": "the test"}"#;
        let app = super::create_app(tauri::test::mock_builder());
        let window = app.get_window("main").unwrap();
        tauri::test::assert_ipc_response(
            &window,
            tauri::InvokePayload {
                cmd: "greet".into(),
                tauri_module: None,
                callback: tauri::api::ipc::CallbackFn(0),
                error: tauri::api::ipc::CallbackFn(1),
                inner: serde_json::from_str(data).unwrap(),
            },
            Ok("Hello, the test! You've been greeted from Rust!"),
        );
    }
}

However, it seems there has been a recent update to the Tauri runtime where an invoke_key is now required. So now the tauri::InvokePayload now requires it and it fails if a matching value to the internal key is not provided:

received ipc message without a __TAURI_INVOKE_KEY__
thread 'nebula::api::tests::should_return_0_with_no_loaded_models' panicked at /Users/osp/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tauri-1.6.7/src/test/mod.rs:318:38:
called `Result::unwrap()` on an `Err` value: InvokeKey
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

How is one supposed to write tests for the exposed Rust code? There is no documentation on how to achieve this.

Edit: This PR added reference to invoke_key everywhere, but there is no way to retrieve it in a test context.

[lucasfernog]

We fixed this issue on v2 but didn't apply the same fix for v1, and it wasn't catch by CI because we applied this patch on a GitHub private fork from an advisory, which doesn't run CI tests by default. A fix will be deployed today.

[lucasfernog]

fix available on 1.6.8, you now must add invoke_key: Some(tauri::test::INVOKE_KEY.into()), to your payload

[ospfranco]

Thank you!

[ospfranco]

Also, what about docs, is this the correct way to write tests for the JS commands?

[ospfranco]

The way issues are closed and then never looked at again is frustrating. In any case, somebody stumbles upon this issue I've done a small write-up on how to write tests for JS commands:

https://ospfranco.com/writting-tests-for-tauri-rust-commands/