Crash when running UI tests in parallel

[ccornelis]

When I configure my test plan to run UI tests in parallel, a crash in SBTUITestTunnelServer.m occurs.
The test plan runs fine when not running tests in parallel.
In my case Xcode runs 5 UI test simulators (clones) in parallel.

[SBTUITestTunnel] Shutting down with error: '[SBTUITestTunnelClient] Failed getting IPC proxy, Error Domain=DTXIPCErrorDomain Code=1 "Connection <DTXIPCConnection: 0x60000260c4e0> is invalid." UserInfo={NSLocalizedDescription=Connection <DTXIPCConnection: 0x60000260c4e0> is invalid.}' *** Assertion failure in -[SBTUITunneledApplication tunnelClient:didShutdownWithError:], SBTUITunneledApplication.m:57 *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '[SBTUITestTunnelClient] Failed getting IPC proxy, Error Domain=DTXIPCErrorDomain Code=1 "Connection <DTXIPCConnection: 0x60000260c4e0> is invalid." UserInfo={NSLocalizedDescription=Connection <DTXIPCConnection: 0x60000260c4e0> is invalid.}' *** First throw call stack: ( 0 CoreFoundation 0x0000000180491128 __exceptionPreprocess + 172 1 libobjc.A.dylib 0x000000018008412c objc_exception_throw + 56 2 Foundation 0x0000000180d1163c _userInfoForFileAndLine + 0 3 BonsaiUITests 0x000000011a9b4c04 -[SBTUITunneledApplication tunnelClient:didShutdownWithError:] + 180 4 BonsaiUITests 0x000000011a9adf74 -[SBTUITestTunnelClient shutDownWithError:] + 220 5 BonsaiUITests 0x000000011a9adffc -[SBTUITestTunnelClient shutDownWithErrorMessage:code:] + 104 6 BonsaiUITests 0x000000011a9ae7f4 __54-[SBTUITestTunnelClient launchTunnelWithStartupBlock:]_block_invoke + 116 7 BonsaiUITests 0x000000011a9a4c70 -[_DTXIPCDistantObject forwardInvocation:] + 704 8 CoreFoundation 0x0000000180495054 ___forwarding___ + 732 9 CoreFoundation 0x000000018049759c _CF_forwarding_prep_0 + 92 10 BonsaiUITests 0x000000011a9b3d04 -[SBTUITestTunnelClient sendSynchronousRequestWithPath:params:assertOnError:] + 1652 11 BonsaiUITests 0x000000011a9af234 -[SBTUITestTunnelClient stubRequestsMatching:response:] + 244 12 BonsaiUITests 0x000000011a9b4e60 -[SBTUITunneledApplication stubRequestsMatching:response:] + 96 13 BonsaiUITests 0x000000011a94d1e8 $s13BonsaiUITests0A10UITestCaseC13stubConstants20forceAddFirstAccountySb_tF + 288 14 BonsaiUITests 0x000000011a94d250 $s13BonsaiUITests0A10UITestCaseC13stubConstants20forceAddFirstAccountySb_tFTo + 40 15 BonsaiUITests 0x000000011a93138c $s13BonsaiUITests0A10UITestCaseC5setUpyyFyycfU_ + 232 16 BonsaiUITests 0x000000011a931534 $sIeg_IeyB_TR + 28 17 BonsaiUITests 0x000000011a9aeeec __42-[SBTUITestTunnelClient serverDidConnect:]_block_invoke + 224 18 libdispatch.dylib 0x000000018016b4f4 _dispatch_call_block_and_release + 24 19 libdispatch.dylib 0x000000018016cd3c _dispatch_client_callout + 16 20 libdispatch.dylib 0x000000018017bb24 _dispatch_main_queue_drain + 1272 21 libdispatch.dylib 0x000000018017b61c _dispatch_main_queue_callback_4CF + 40 22 CoreFoundation 0x00000001803f1a30 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 12 23 CoreFoundation 0x00000001803ec148 __CFRunLoopRun + 1936 24 CoreFoundation 0x00000001803eb5a4 CFRunLoopRunSpecific + 572 25 XCTestCore 0x0000000105bcad48 +[XCTWaiter _synchronouslyWaitForTimeInterval:] + 112 26 XCTestCore 0x0000000105bcb2d4 -[XCTWaiter _performWait:manager:completionHandler:] + 516 27 XCTestCore 0x0000000105bc9310 -[XCTWaiter _waitForExpectations:timeout:enforceOrder:synchronously:completionHandler:] + 528 28 XCTestCore 0x0000000105bc90b0 -[XCTWaiter waitForExpectations:timeout:enforceOrder:] + 108 29 XCTestCore 0x0000000105bc94f8 +[XCTWaiter waitForExpectations:timeout:enforceOrder:] + 76 30 XCUIAutomation 0x000000010497d328 XCUIWaitAndLog + 128 31 XCUIAutomation 0x0000000104952954 __67-[XCUIApplicationProcess waitForQuiescenceIncludingAnimationsIdle:]_block_invoke + 216 32 XCTestCore 0x0000000105bc2c00 -[XCTContext _runActivityNamed:type:block:] + 196 33 XCTestCore 0x0000000105bc17e8 -[XCTContext runInternalActivityNamed:block:] + 124 34 XCUIAutomation 0x0000000104952848 -[XCUIApplicationProcess waitForQuiescenceIncludingAnimationsIdle:] + 212 35 XCUIAutomation 0x000000010495d780 __42-[XCUIApplicationImpl _launchWithRequest:]_block_invoke + 996 36 XCTestCore 0x0000000105bc2c00 -[XCTContext _runActivityNamed:type:block:] + 196 37 XCTestCore 0x0000000105bc17e8 -[XCTContext runInternalActivityNamed:block:] + 124 38 XCUIAutomation 0x000000010495d354 -[XCUIApplicationImpl _launchWithRequest:] + 224 39 XCTestCore 0x0000000105bc2c00 -[XCTContext _runActivityNamed:type:block:] + 196 40 XCTestCore 0x0000000105bc17e8 -[XCTContext runInternalActivityNamed:block:] + 124 41 XCUIAutomation 0x000000010495cd9c -[XCUIApplicationImpl serviceOpenRequest:] + 344 42 XCUIAutomation 0x0000000104972fcc -[XCUIApplication _launchUsingXcode:withoutAccessibility:launchURL:] + 296 43 BonsaiUITests 0x000000011a9ae570 -[SBTUITestTunnelClient launchTunnelWithStartupBlock:] + 1352 44 BonsaiUITests 0x000000011a9b4cc0 -[SBTUITunneledApplication launchTunnelWithStartupBlock:] + 72 45 BonsaiUITests 0x000000011a9b4b1c -[SBTUITunneledApplication launchTunnelWithOptions:startupBlock:] + 148 46 BonsaiUITests 0x000000011a9310d4 $s13BonsaiUITests0A10UITestCaseC5setUpyyF + 2248 47 BonsaiUITests 0x000000011a931560 $s13BonsaiUITests0A10UITestCaseC5setUpyyFTo + 28 48 BonsaiUITests 0x000000011a92d3ac $s13BonsaiUITests23OnboardingLongFlowTestsC5setUpyyFToTm + 136 49 XCTestCore 0x0000000105be086c __70-[XCTestCase _shouldContinueAfterPerformingSetUpSequenceWithSelector:]_block_invoke.134 + 16 50 XCTestCore 0x0000000105ba4ad4 -[XCTestCase(XCTIssueHandling) _caughtUnhandledDeveloperExceptionPermittingControlFlowInterruptions:caughtInterruptionException:whileExecutingBlock:] + 160 51 XCTestCore 0x0000000105be04b0 __70-[XCTestCase _shouldContinueAfterPerformingSetUpSequenceWithSelector:]_block_invoke_2 + 48 52 XCTestCore 0x0000000105be0420 __70-[XCTestCase _shouldContinueAfterPerformingSetUpSequenceWithSelector:]_block_invoke + 308 53 XCTestCore 0x0000000105bc2c00 -[XCTContext _runActivityNamed:type:block:] + 196 54 XCTestCore 0x0000000105bc17e8 -[XCTContext runInternalActivityNamed:block:] + 124 55 XCTestCore 0x0000000105bc16c4 +[XCTContext runInternalActivityNamed:block:] + 96 56 XCTestCore 0x0000000105bdebb4 -[XCTestCase _shouldContinueAfterPerformingSetUpSequenceWithSelector:] + 140 57 XCTestCore 0x0000000105bde810 -[XCTestCase invokeTest] + 548 58 XCTestCore 0x0000000105be00d0 __26-[XCTestCase performTest:]_block_invoke.116 + 32 59 XCTestCore 0x0000000105ba4ad4 -[XCTestCase(XCTIssueHandling) _caughtUnhandledDeveloperExceptionPermittingControlFlowInterruptions:caughtInterruptionException:whileExecutingBlock:] + 160 60 XCTestCore 0x0000000105bdfb94 __26-[XCTestCase performTest:]_block_invoke.106 + 492 61 XCTestCore 0x0000000105bc3244 +[XCTContext _runInChildOfContext:forTestCase:markAsReportingBase:block:] + 172 62 XCTestCore 0x0000000105bc3144 +[XCTContext runInContextForTestCase:markAsReportingBase:block:] + 100 63 XCTestCore 0x0000000105bdf640 -[XCTestCase performTest:] + 248 64 XCTestCore 0x0000000105b90a38 -[XCTest runTest] + 44 65 XCTestCore 0x0000000105bc61bc -[XCTestSuite runTestBasedOnRepetitionPolicy:testRun:] + 64 66 XCTestCore libc++abi: terminating due to uncaught exception of type NSException

[tcamin]

This might have been addressed recently in #212. If not please reopen the issue, thanks!

[ccornelis]

I tried to run our UI tests with the latest SBUITestTunnel master, but unfortunately the issue is still there.

I don't think I can reopen the issue because I'm not a repo collaborator.

[tcamin]

Did you try disabling IPC as described here?

[ccornelis]

I gave it a try and with good results. No more crashes.
Thanks @tcamin for the 💯 support!

[tcamin]

🙌