chore: spurious failure in rt_common test

[carllerche]

This test failed on the windows CI run. It looks like it depends on timing, which is going to be unreliable on CI machines.

Output

failures:

---- threaded_scheduler_4_threads::coop_unconstrained stdout ----
thread 'threaded_scheduler_4_threads::coop_unconstrained' panicked at 'assertion failed: Pin::new(task).poll(cx).is_ready()', tokio\tests\rt_common.rs:1038:21
stack backtrace:
   0: std::panicking::begin_panic_handler
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\/library\std\src\panicking.rs:498
   1: core::panicking::panic_fmt
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\/library\core\src\panicking.rs:107
   2: core::panicking::panic
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\/library\core\src\panicking.rs:48
   3: rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0::closure$1
             at .\tests\rt_common.rs:1038
   4: futures_util::future::poll_fn::impl$2::poll<tuple$<>,rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0::closure$1>
             at C:\Users\runneradmin\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-util-0.3.19\src\future\poll_fn.rs:56
   5: tokio::task::unconstrained::impl$0::poll::closure$0<futures_util::future::poll_fn::PollFn<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0::closure$1> >
             at .\src\task\unconstrained.rs:25
   6: tokio::coop::with_budget::closure$0<enum$<core::task::poll::Poll<tuple$<> > >,tokio::task::unconstrained::impl$0::poll::closure$0>
             at .\src\coop.rs:102
   7: std::thread::local::LocalKey<core::cell::Cell<tokio::coop::Budget> >::try_with<core::cell::Cell<tokio::coop::Budget>,tokio::coop::with_budget::closure$0,enum$<core::task::poll::Poll<tuple$<> > > >
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\library\std\src\thread\local.rs:399
   8: std::thread::local::LocalKey<core::cell::Cell<tokio::coop::Budget> >::with<core::cell::Cell<tokio::coop::Budget>,tokio::coop::with_budget::closure$0,enum$<core::task::poll::Poll<tuple$<> > > >
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\library\std\src\thread\local.rs:375
   9: tokio::coop::with_budget
             at .\src\coop.rs:95
  10: tokio::coop::with_unconstrained
             at .\src\coop.rs:79
  11: tokio::task::unconstrained::impl$0::poll<futures_util::future::poll_fn::PollFn<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0::closure$1> >
             at .\src\task\unconstrained.rs:25
  12: rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0
             at .\tests\rt_common.rs:1035
  13: core::future::from_generator::impl$1::poll<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0>
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\library\core\src\future\mod.rs:80
  14: tracing::instrument::impl$0::poll<core::future::from_generator::GenFuture<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0> >
             at C:\Users\runneradmin\.cargo\registry\src\github.com-1ecc6299db9ec823\tracing-0.1.29\src\instrument.rs:272
  15: tokio::park::thread::impl$5::block_on::closure$0<tracing::instrument::Instrumented<core::future::from_generator::GenFuture<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0> > >
             at .\src\park\thread.rs:263
  16: tokio::coop::with_budget::closure$0<enum$<core::task::poll::Poll<tuple$<> > >,tokio::park::thread::impl$5::block_on::closure$0>
             at .\src\coop.rs:102
  17: std::thread::local::LocalKey<core::cell::Cell<tokio::coop::Budget> >::try_with<core::cell::Cell<tokio::coop::Budget>,tokio::coop::with_budget::closure$0,enum$<core::task::poll::Poll<tuple$<> > > >
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\library\std\src\thread\local.rs:399
  18: std::thread::local::LocalKey<core::cell::Cell<tokio::coop::Budget> >::with<core::cell::Cell<tokio::coop::Budget>,tokio::coop::with_budget::closure$0,enum$<core::task::poll::Poll<tuple$<> > > >
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\library\std\src\thread\local.rs:375
  19: tokio::coop::with_budget
             at .\src\coop.rs:95
  20: tokio::coop::budget
             at .\src\coop.rs:72
  21: tokio::park::thread::CachedParkThread::block_on<tracing::instrument::Instrumented<core::future::from_generator::GenFuture<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0> > >
             at .\src\park\thread.rs:263
  22: tokio::runtime::enter::Enter::block_on<tracing::instrument::Instrumented<core::future::from_generator::GenFuture<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0> > >
             at .\src\runtime\enter.rs:151
  23: tokio::runtime::thread_pool::ThreadPool::block_on<tracing::instrument::Instrumented<core::future::from_generator::GenFuture<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0> > >
             at .\src\runtime\thread_pool\mod.rs:73
  24: tokio::runtime::Runtime::block_on<core::future::from_generator::GenFuture<rt_common::threaded_scheduler_4_threads::coop_unconstrained::generator$0> >
             at .\src\runtime\mod.rs:477
  25: rt_common::threaded_scheduler_4_threads::coop_unconstrained
             at .\tests\rt_common.rs:1026
  26: rt_common::threaded_scheduler_4_threads::coop_unconstrained::closure$0
             at .\tests\rt_common.rs:1021
  27: core::ops::function::FnOnce::call_once<rt_common::threaded_scheduler_4_threads::coop_unconstrained::closure$0,tuple$<> >
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\library\core\src\ops\function.rs:227
  28: core::ops::function::FnOnce::call_once
             at /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b\library\core\src\ops\function.rs:227
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

[Hodkinson]

I think this one was fixed by #5074