Open Radar

 
Summary:
After successfully running tests regularly for weeks on a machine with Xcode installed, the tests will no longer execute. It appears that Xcode can no longer find the Simulator or its devices. Deleting the Simulator devices from the Devices menu in Xcode (and all directories in ~/Library/Developer/CoreSimulator/Devices) and adding them back again does not help.

Steps to Reproduce:
Select the Test menu item. The test target will be built but never executed in a Simulator device.

Expected Results:
The test runner would launch the Simulator and run the test target in it. Upon completing it would report which tests passed or failed.

Actual Results:
The Simulator does not launch and no error messages are output in Xcode. Opening system.log in Console.app reveals the following message:

Nov 21 16:21:29 jenkinss-mini.home xcodebuild[51853]: [MT] DVTAssertions: Warning in /SourceCache/IDEFrameworks/IDEFrameworks-6604/IDEFoundation/Testing/OCUnit/IDEOCUnitTestRunner.m:388
	Details:  No baseline file matching runDestinationRecord: {
	    localComputer =     {
	        busSpeedInMHz = 100;
	        cpuCount = 1;
	        cpuKind = "Intel Core i5";
	        cpuSpeedInMHz = 2500;
	        logicalCPUCoresPerPackage = 4;
	        modelCode = "Macmini6,1";
	        physicalCPUCoresPerPackage = 2;
	        platformIdentifier = "com.apple.platform.macosx";
	    };
	    targetArchitecture = i386;
	    targetDevice =     {
	        modelCode = "iPhone5,1";
	        platformIdentifier = "com.apple.platform.iphonesimulator";
	    };
	}
	Object:   <Xcode3OCUnitTestRunner: 0x7fa0d6b61550>
	Method:   -_scheduledTestArgumentsOperationForBuildParameters:launchParameters:runDestination:workspace:testRunIdentifier:testRunIdentifiers:actionResultsBundleWithBaselineOverridesFilePath:error:completionBlock:
	Thread:   <NSThread: 0x7fa0d0514030>{name = (null), num = 1}
	Please file a bug at http://bugreport.apple.com with this warning message and any useful information you can provide.