Xcode 11.5 Running XCTest - Timed out waiting and always fail unit test

ENV: macOS: catalina 10.15.4 XCODE: 11.5 (11E608c)

I start a new project and add one very simple unit test as below:

Code Block
func testExample() throws {
XCTAssertEqual(0, 0)
}

It builds successfully and simulator works well, my app launched successfully, but the unit testing is always waiting to init and run tests, everytime i failed to start unitest and i always get the following crashing error:
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGSTOP

the whole error message is like the following:
Code Block
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGSTOP
* frame #0: 0x00007fff51b5adfa libsystem_kernel.dylib`mach_msg_trap + 10
frame #1: 0x00007fff51b5b170 libsystem_kernel.dylib`mach_msg + 60
frame #2: 0x00007fff23da0595 CoreFoundation`CFRunLoopServiceMachPort + 165
frame #3: 0x00007fff23d9b1c7 CoreFoundation`CFRunLoopRun + 1383
frame #4: 0x00007fff23d9a944 CoreFoundation`CFRunLoopRunSpecific + 404
frame #5: 0x00007fff38ba6c1a GraphicsServices`GSEventRunModal + 139
frame #6: 0x00007fff48c8b9ec UIKitCore`UIApplicationMain + 1605
frame #7: 0x000000010e286d2b iep-ios-app`main at AppDelegate.swift:15:7
frame #8: 0x00007fff51a231fd libdyld.dylib`start + 1
frame #9: 0x00007fff51a231fd libdyld.dylib`start + 1
thread #6, name = 'com.apple.uikit.eventfetch-thread'
frame #0: 0x00007fff51b5adfa libsystem_kernel.dylib`mach_msg_trap + 10
frame #1: 0x00007fff51b5b170 libsystem_kernel.dylib`mach_msg + 60
frame #2: 0x00007fff23da0595 CoreFoundation`CFRunLoopServiceMachPort + 165
frame #3: 0x00007fff23d9b1c7 CoreFoundation`CFRunLoopRun + 1383
frame #4: 0x00007fff23d9a944 CoreFoundation`CFRunLoopRunSpecific + 404
frame #5: 0x00007fff25939c71 Foundation`-[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 211
frame #6: 0x00007fff25939ee0 Foundation`-[NSRunLoop(NSRunLoop) runUntilDate:] + 72
frame #7: 0x00007fff48d39bfb UIKitCore`-[UIEventFetcher threadMain] + 138
frame #8: 0x00007fff2594f9eb Foundation`NSThreadstart + 1047
frame #9: 0x00007fff51c0c109 libsystem_pthread.dylib`_pthread_start + 148
frame #10: 0x00007fff51c07b8b libsystem_pthread.dylib`thread_start + 15
thread #14, name = 'com.apple.NSURLConnectionLoader'
frame #0: 0x00007fff51b5adfa libsystem_kernel.dylib`mach_msg_trap + 10
frame #1: 0x00007fff51b5b170 libsystem_kernel.dylib`mach_msg + 60
frame #2: 0x00007fff23da0595 CoreFoundation`CFRunLoopServiceMachPort + 165
frame #3: 0x00007fff23d9b1c7 CoreFoundation`CFRunLoopRun + 1383
frame #4: 0x00007fff23d9a944 CoreFoundation`CFRunLoopRunSpecific + 404
frame #5: 0x00007fff23159df3 CFNetwork`_lldb_unnamed_symbol11344$$CFNetwork + 182
frame #6: 0x00007fff2594f9eb Foundation`NSThreadstart + 1047
frame #7: 0x00007fff51c0c109 libsystem_pthread.dylib`_pthread_start + 148
frame #8: 0x00007fff51c07b8b libsystem_pthread.dylib`thread_start + 15
thread #21
frame #0: 0x00007fff51b5c4ce libsystem_kernel.dylib`workq_kernreturn + 10
frame #1: 0x00007fff51c08aa1 libsystem_pthread.dylib`_pthread_wqthread + 390
frame #2: 0x00007fff51c07b77 libsystem_pthread.dylib`start_wqthread + 15


Possible actions:
I updated my mac os , and try to kill all other process on my computer, it's still not solved. Is there any xcode version bug? or what should i do to downgrade the xcode version?

I'm using the same Xcode build and macOS version as yours and was not able to reproduce the bug, did you change something on the build schemes? Or on the implementation of the test class?

You cannot downgrade the Xcode via App Store, but you can download previous versions on this link and then select the version of Xcode you want to download.
When you try to run your tests in the simulator, is the issue that the app launches, but the unit tests never start running? And then you end up explicitly canceling the test operation? Or do the tests start to run but immediately crash?

Either way, if this is reproducing for you with a sample project, please do file a Feedback Assistant so that we can investigate further!
Xcode 11.5 Running XCTest - Timed out waiting and always fail unit test
 
 
Q