How to upgrade winit to 0.30 for triangle example and cfg=wasm32?

[XCemaXX]

I have the problem with triangle example. I want to upgrade winit from 0.29.15 to 0.30. But doesn't know how.
I suspect that I need to use wasm_bindgen_futures and doesn't use pollster.
In winit there is EventLoopExtWebSys::spawn_app() method. Maybe it should be use somehow with wasm_bindgen_futures.
In 0.29.15 we have:

pub fn main() {
    let event_loop = EventLoop::new().unwrap();
    let mut builder = winit::window::WindowBuilder::new();
    //...
    builder = builder.with_canvas(Some(canvas));
    let window = builder.build(&event_loop).unwrap();
    wasm_bindgen_futures::spawn_local(run(event_loop, window));
}

async fn run(event_loop: EventLoop<()>, window: Window) { 
/* init render staff basdd on window */ 
/* request adapter and device in async function. It is a problem in winit 0.30 */
    /* run event loop */
}

I tried my best and changed code. It is compilable, but I cannot init render staff. With winit 0.30 my code looks like:

struct App {
    window: Option<Window>,
}

pub fn main() {
    let event_loop = EventLoop::new().unwrap();
    let mut app = App{window: None};
    let _ = event_loop.run_app(&mut app); // <= problem here. I don't know how to run with wasm_bindgen_futures
    // ... init of window will be later in App::resumed
}

impl ApplicationHandler for App {
    fn resumed(&mut self, event_loop: &ActiveEventLoop) { // <= not async
        use winit::platform::web::WindowAttributesExtWebSys;
        // ...
        self.window = Some(event_loop.create_window(Window::default_attributes().with_canvas(canvas)).unwrap());
        /* init render staff basdd on window */ 
        /* request adapter and device in async function. It is a problem. I tried run it with pollster. But I did't get an image on website */
        pollster::block_on(instance.request_adapter(/*...*/))
        pollster::block_on(instance.request_device(/*...*/))
    }
    fn window_event(&mut self, event_loop: &ActiveEventLoop, _id: WindowId, event: WindowEvent) {
        /* it is ok. Replacement of event loop */
    }
}

I got panics

hello_wasm.js:409 panicked at library/std/src/sys/sync/condvar/no_threads.rs:20:9: condvar wait not supported Stack: Error at http://localhost:7014/pkg/hello_wasm.js:415:21 at logError (http://localhost:7014/pkg/hello_wasm.js:240:18) at imports.wbg.__wbg_new_abda76e883ba8a5f (http://localhost:7014/pkg/hello_wasm.js:414:66) at hello_wasm.wasm.console_error_panic_hook::Error::new::haf98a4b62c108c1a (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[26729]:0xb4d0ec) at hello_wasm.wasm.console_error_panic_hook::hook_impl::hb9370c8528bc0553 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[6002]:0x7d29c5) at hello_wasm.wasm.console_error_panic_hook::hook::h6af5d3f7503eb62c (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[31903]:0xb9e54b) at hello_wasm.wasm.core::ops::function::Fn::call::h07d6c5b0ceb9e440 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[28545]:0xb6d150) at hello_wasm.wasm.std::panicking::rust_panic_with_hook::h32c80a64fe4de396 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[11372]:0x9554de) at hello_wasm.wasm.std::panicking::begin_panic_handler::{{closure}}::hd496964d114e98b9 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[15495]:0xa1659d) at hello_wasm.wasm.std::sys_common::backtrace::__rust_end_short_backtrace::h0d4686a7fe3981a4 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[38175]:0xbdd5db)

hello_wasm_bg.wasm:0xbdd6a3 Uncaught (in promise) RuntimeError: unreachable
at hello_wasm.wasm.__rust_start_panic (hello_wasm_bg.wasm:0xbdd6a3)
at hello_wasm.wasm.rust_panic (hello_wasm_bg.wasm:0xbdca21)
at hello_wasm.wasm.std::panicking::rust_panic_with_hook::h32c80a64fe4de396 (hello_wasm_bg.wasm:0x95550e)
at hello_wasm.wasm.std::panicking::begin_panic_handler::{{closure}}::hd496964d114e98b9 (hello_wasm_bg.wasm:0xa1659d)
at hello_wasm.wasm.std::sys_common::backtrace::__rust_end_short_backtrace::h0d4686a7fe3981a4 (hello_wasm_bg.wasm:0xbdd5db)
at hello_wasm.wasm.rust_begin_unwind (hello_wasm_bg.wasm:0xb832c0)
at hello_wasm.wasm.core::panicking::panic_fmt::hc7427f902a13f1a9 (hello_wasm_bg.wasm:0xb9c78b)
at hello_wasm.wasm.std::sys::sync::condvar::no_threads::Condvar::wait::h26a7db7c4c9c1502 (hello_wasm_bg.wasm:0xbbaaa9)
at hello_wasm.wasm.std::sync::condvar::Condvar::wait::h778b12245385c270 (hello_wasm_bg.wasm:0x9c07ab)
at hello_wasm.wasm.pollster::Signal::wait::h517257285e07e67c (hello_wasm_bg.wasm:0x7970f5)

hello_wasm.js:409 panicked at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/sys/sync/mutex/no_threads.rs:20:9:
assertion left == right failed: cannot recursively acquire mutex
left: true
right: false
Stack:
Error
at http://localhost:7014/pkg/hello_wasm.js:415:21
at logError (http://localhost:7014/pkg/hello_wasm.js:240:18)
at imports.wbg.__wbg_new_abda76e883ba8a5f (http://localhost:7014/pkg/hello_wasm.js:414:66)
at hello_wasm.wasm.console_error_panic_hook::Error::new::haf98a4b62c108c1a (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[26729]:0xb4d0ec)
at hello_wasm.wasm.console_error_panic_hook::hook_impl::hb9370c8528bc0553 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[6002]:0x7d29c5)
at hello_wasm.wasm.console_error_panic_hook::hook::h6af5d3f7503eb62c (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[31903]:0xb9e54b)
at hello_wasm.wasm.core::ops::function::Fn::call::h07d6c5b0ceb9e440 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[28545]:0xb6d150)
at hello_wasm.wasm.std::panicking::rust_panic_with_hook::h32c80a64fe4de396 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[11372]:0x9554de)
at hello_wasm.wasm.std::panicking::begin_panic_handler::{{closure}}::hd496964d114e98b9 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[15495]:0xa1656a)
at hello_wasm.wasm.std::sys_common::backtrace::__rust_end_short_backtrace::h0d4686a7fe3981a4 (http://localhost:7014/pkg/hello_wasm_bg.wasm:wasm-function[38175]:0xbdd5db)

hello_wasm_bg.wasm:0xbdd6a3 Uncaught (in promise) RuntimeError: unreachable
at hello_wasm.wasm.__rust_start_panic (hello_wasm_bg.wasm:0xbdd6a3)
at hello_wasm.wasm.rust_panic (hello_wasm_bg.wasm:0xbdca21)
at hello_wasm.wasm.std::panicking::rust_panic_with_hook::h32c80a64fe4de396 (hello_wasm_bg.wasm:0x95550e)
at hello_wasm.wasm.std::panicking::begin_panic_handler::{{closure}}::hd496964d114e98b9 (hello_wasm_bg.wasm:0xa1656a)
at hello_wasm.wasm.std::sys_common::backtrace::__rust_end_short_backtrace::h0d4686a7fe3981a4 (hello_wasm_bg.wasm:0xbdd5db)
at hello_wasm.wasm.rust_begin_unwind (hello_wasm_bg.wasm:0xb832c0)
at hello_wasm.wasm.core::panicking::panic_fmt::hc7427f902a13f1a9 (hello_wasm_bg.wasm:0xb9c78b)
at hello_wasm.wasm.core::panicking::assert_failed_inner::h0379ad51ee2a5759 (hello_wasm_bg.wasm:0x7e8ded)
at hello_wasm.wasm.core::panicking::assert_failed::h8b3ec1130970f769 (hello_wasm_bg.wasm:0xaedeaa)
at hello_wasm.wasm.std::sync::mutex::Mutex::lock::hd53279bccb702598 (hello_wasm_bg.wasm:0x6f5edd)

Guys, help please.

[XCemaXX]

So there is the related topic rust-windowing/winit#3667

[XCemaXX]

There is a lot of related issues. So I will leave the links and close this one.
rust-windowing/winit#3667
https://users.rust-lang.org/t/winit-0-30-wgpu-0-20-init-lifetime-issue/110693/6
rust-windowing/winit#3626
rust-windowing/winit#3560
#5709

[matthewjberger]

@XCemaXX I made an example repo that might help

[XCemaXX]

Hi @matthewjberger, thank you very much for the example — I updated my code and it works!

However, I’ve encountered an issue: for every frame, I see the following message in the debug console:
Device::maintain: waiting for submission index N
It seems to be connected with the following part of the code:

self.queue.submit(std::iter::once(encoder.finish())); // <-----
frame.present();

I believe I need to wait for the command to finish somehow, but I’m not sure how to properly do this. Do you experience the same issue in your example? I haven’t been able to find a solution yet.
If you want to take a look, my changes are in this branch.
Thanks again for your help!

[XCemaXX]

maybe its connected with #3601