[MT][browser] System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests fails

[ilonatommy]

After enabling all MT library tests (#91536)

[FAIL] System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests
 RunContinueWhenAnyTests: > FAILED! continuation.Wait() should throw exception iff preCanceledToken
 Expected: True
 Actual:   False
   at System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests()
    at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
    at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)

[ghost]

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Issue Details

---

After enabling all MT library tests (#91536)

[FAIL] System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests
 RunContinueWhenAnyTests: > FAILED! continuation.Wait() should throw exception iff preCanceledToken
 Expected: True
 Actual:   False
   at System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests()
    at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
    at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)

Author:	ilonatommy
Assignees:	-
Labels:	arch-wasm, disabled-test, area-Build-mono, area-VM-threading-mono
Milestone:	-

[radekdoulik]

This is still valid issue.

Interestingly the test passes when run with the other tests.

When I run it separately, it deadlocks with:

  info: Initializing dotnet version 9.0.0-dev commit hash 75dc1b3cd2a92df13fdc383212d1c2d8a7928f19
  info: Discovering: System.Threading.Tasks.Tests.dll (method display = ClassAndMethod, method display options = None)
  info: Discovered:  System.Threading.Tasks.Tests.dll (found 1 of 787 test cases)
  info: Using random seed for test cases: 304684785
  info: Using random seed for collections: 304684785
  info: Starting:    System.Threading.Tasks.Tests.dll
  warn: Blocking on the main thread is very dangerous, see https://emscripten.org/docs/porting/pthreads.html#blocking-on-the-main-browser-thread
  warn: MONO_WASM [0xf3d3c-main]: Failed to find loaded WebWorker, this may deadlock. Please increase the pthreadPoolSize.

[pavelsavara]

how many threads we think it should use ? I see something like (2^6)*3 tasks being created, some of them long running.

[maraf]

Current failure is

  fail: [FAIL] System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests
  info: System.PlatformNotSupportedException : Blocking wait is not supported on the JS interop threads.
  info:    at System.Threading.Thread.AssureBlockingPossible() in C:\Development\dotnet\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\Thread.cs:line 683
  info:    at System.Threading.Monitor.Wait(Object obj, Int32 millisecondsTimeout) in C:\Development\dotnet\runtime\src\mono\System.Private.CoreLib\src\System\Threading\Monitor.Mono.cs:line 81
  info:    at System.Threading.ManualResetEventSlim.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken) in C:\Development\dotnet\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\ManualResetEventSlim.cs:line 573
  info:    at System.Threading.Tasks.Task.SpinThenBlockingWait(Int32 millisecondsTimeout, CancellationToken cancellationToken) in C:\Development\dotnet\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\Tasks\Task.cs:line 3068
  info:    at System.Threading.Tasks.Task.InternalWaitCore(Int32 millisecondsTimeout, CancellationToken cancellationToken) in C:\Development\dotnet\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\Tasks\Task.cs:line 3003
  info:    at System.Threading.Tasks.Task.InternalWait(Int32 millisecondsTimeout, CancellationToken cancellationToken) in C:\Development\dotnet\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\Tasks\Task.cs:line 2962
  info:    at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken) in C:\Development\dotnet\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\Tasks\Task.cs:line 2764
  info:    at System.Threading.Tasks.Task.Wait() in C:\Development\dotnet\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\Tasks\Task.cs:line 2623
  info:    at System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests() in C:\Development\dotnet\runtime\src\libraries\System.Runtime\tests\System.Threading.Tasks.Tests\Task\TaskContinueWhenAnyTests.cs:line 93
  info:    at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args) in C:\Development\dotnet\runtime\src\mono\System.Private.CoreLib\src\System\Reflection\MethodBaseInvoker.Mono.cs:line 22
  info:    at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr) in C:\Development\dotnet\runtime\src\libraries\System.Private.CoreLib\src\System\Reflection\MethodBaseInvoker.cs:line 57
  info: Finished:    System.Threading.Tasks.Tests.dll

[pavelsavara]

Right now, we are invoking the test on the thread pool thread. And so I wonder how did we get to UI thread.

cc @radekdoulik

[pavelsavara]

let's re-test with latest main

[ilonatommy]

This is not blocked on main. Closing.