thread 'main' panicked at 'A Tokio 1.x context was found, but timers are disabled. Call enable_time on the runtime builder to enable timers.'

[Hans-Wu-cn]

How to solve the panic when using asynchrony? The code is as follows.

pub fn get_device(services: &[Uuid]) -> (Vec<String>, Device) {
    let rt = Runtime::new().unwrap();
    let future= async {
        let adapter = Adapter::default().await.unwrap();
        adapter.wait_available().await.unwrap();
        info!("looking for device");
        let device = adapter
            .discover_devices(services)
            .await
            .unwrap()
            .next()
            .await
            .ok_or("Failed to discover device")
            .unwrap()
            .unwrap();
        println!(
            "found device: {} ({:?})",
            device.name_async().await.as_deref().unwrap_or("(unknown)"),
            device.id()
        );
        let services = services.clone();
        for uuid in services {
            UUID_STR_VEC.write().await.push(uuid.to_string());
        }
        (UUID_STR_VEC.read().await.to_vec(),device)
    };
    rt.block_on(future)
}

[Darksonn]

You're creating a runtime without timers enabled somewhere in your program. It isn't in the snippet you shared, since Runtime::new() does enable timers.

[Hans-Wu-cn]

Do you mean that the timer has not been called? Because machine translation may have errors with your meaning, what should I do? I thought rt.block_ On (future) is enabled
I modified a part of this function, and there will be no panic after the modification, but it is suspected that there will be a deadlock at the end of the execution of this function

lazy_static! {
    pub static ref UUID_STR_VEC: RwLock<Vec<String>> = RwLock::new(Vec::new());
}

pub fn get_device(services: &[Uuid]) -> (Vec<String>, Device) {
    let rt = Runtime::new().unwrap();
    let future= async {
        let adapter = Adapter::default().await.unwrap();
        adapter.wait_available().await.unwrap();
        info!("looking for device");
        let device = adapter
            .discover_devices(services)
            .await
            .unwrap()
            .next()
            .await
            .ok_or("Failed to discover device")
            .unwrap()
            .unwrap();
        println!(
            "found device: {} ({:?})",
            device.name_async().await.as_deref().unwrap_or("(unknown)"),
            device.id()
        );
        let services = services;
       //update
        let mut uuid_str=UUID_STR_VEC.write().await;
        for uuid in services {
            uuid_str.push(uuid.to_string());
        }
        (UUID_STR_VEC.read().await.to_vec(),device)
    };
    rt.block_on(future)
}

[Darksonn]

As far as I can tell, the problem is not visible in the code you have posted.

[Hans-Wu-cn]

I found out where the problem is because the print log did not add info! ({}) (:?), but the trust-analyzer does not prompt, resulting in an exception