Hello,
It appears that you all have run into this in the past, but it appears to be happening again on the latest 10.0.0 xcode image. Namely, since there are multiple destinations defined with the same name, there is no way to run xcodebuild with iOS or tvOS targets without specifying the UDID, which you recommend against doing here.
I believe last time this occurred, you all removed the duplicate destinations so that our xcodebuild commands could reference the unique name directly.
Thank you for your help!
Available destinations for the "Test" scheme:
{ platform:macOS, arch:x86_64, id:564D3153-6E0B-98A1-B5FD-7DA18465F261 }
{ platform:tvOS Simulator, id:628F76FC-A586-4CB4-BA42-E5F657A15EB5, OS:12.0, name:Apple TV }
{ platform:tvOS Simulator, id:C89C80E7-7710-4B82-9239-8EAC72BF67E1, OS:12.0, name:Apple TV }
{ platform:tvOS Simulator, id:60A58BE0-F375-46EC-8274-09D45F3F0D81, OS:12.0, name:Apple TV 4K }
{ platform:tvOS Simulator, id:616FBCF4-46F9-41A6-BCAF-0076BB519ABA, OS:12.0, name:Apple TV 4K }
{ platform:tvOS Simulator, id:2BC948C7-99A7-4070-B8DD-F7E2AF3927B9, OS:12.0, name:Apple TV 4K (at 1080p) }
{ platform:tvOS Simulator, id:6E723B83-E670-41B1-B6CB-58E1F283D41B, OS:12.0, name:Apple TV 4K (at 1080p) }
{ platform:iOS Simulator, id:84F834E6-99B2-40F9-A679-7F2168CA7FE2, OS:12.0, name:iPad (5th generation) }
{ platform:iOS Simulator, id:EAF9579F-45D8-4EE7-95E7-1C37AA50B468, OS:12.0, name:iPad (5th generation) }
{ platform:iOS Simulator, id:328B5921-7B10-4EE7-B767-77CC3438E990, OS:12.0, name:iPad (6th generation) }
{ platform:iOS Simulator, id:50A3D530-A3F1-4077-B31C-AD925425D89D, OS:12.0, name:iPad (6th generation) }
{ platform:iOS Simulator, id:1A91D85E-5782-4B48-AF6C-5D14F4D0F083, OS:12.0, name:iPad Air }
{ platform:iOS Simulator, id:91759B85-1359-41DE-B1E1-4C78CCBB6C5A, OS:12.0, name:iPad Air }
{ platform:iOS Simulator, id:15CC93ED-5649-49C2-9F57-E23C51739DEF, OS:12.0, name:iPad Air 2 }
{ platform:iOS Simulator, id:7022547A-537D-4137-BBDE-E91B765924AD, OS:12.0, name:iPad Air 2 }
{ platform:iOS Simulator, id:10236A84-08B2-4BFE-90F4-C7F7F64ED3DD, OS:12.0, name:iPad Pro (9.7-inch) }
{ platform:iOS Simulator, id:631D998F-BF14-4976-B0BC-73515A52B8A0, OS:12.0, name:iPad Pro (9.7-inch) }
{ platform:iOS Simulator, id:94A77FDB-FF5A-404A-86CF-B0A022D57E0F, OS:12.0, name:iPad Pro (10.5-inch) }
{ platform:iOS Simulator, id:A597DCAA-6577-464F-9DFF-C65AB59BAA22, OS:12.0, name:iPad Pro (10.5-inch) }
{ platform:iOS Simulator, id:42DD5D74-AE4B-4CC5-AC9D-C9EBAE98AE43, OS:12.0, name:iPad Pro (12.9-inch) }
{ platform:iOS Simulator, id:905D08E7-6D53-46BA-ADE5-AF114BF0E8BE, OS:12.0, name:iPad Pro (12.9-inch) }
{ platform:iOS Simulator, id:7163E442-19EF-4D16-A7A1-45191F272446, OS:12.0, name:iPad Pro (12.9-inch) (2nd generation) }
{ platform:iOS Simulator, id:97BC3E59-5EB7-4619-9D77-A2A203FE2680, OS:12.0, name:iPhone 5s }
{ platform:iOS Simulator, id:A0862298-F8F2-4C89-AE89-0D5B0AB28A39, OS:12.0, name:iPhone 5s }
{ platform:iOS Simulator, id:2B070C46-7D31-4152-8247-937534A714CC, OS:12.0, name:iPhone 6 }
{ platform:iOS Simulator, id:56C07B83-763C-4A72-BC0E-E12A6E838CDB, OS:12.0, name:iPhone 6 }
{ platform:iOS Simulator, id:6085FF72-8F68-44B5-8D4E-3DB8CDBA8E81, OS:12.0, name:iPhone 6 Plus }
{ platform:iOS Simulator, id:9F32C487-FAEC-4ABE-B00D-159EC007E50D, OS:12.0, name:iPhone 6 Plus }
{ platform:iOS Simulator, id:940596C3-FA5D-43AB-8E76-458030078355, OS:12.0, name:iPhone 6s }
{ platform:iOS Simulator, id:C2D0446B-7C39-49FA-AFE3-8C513B7841CB, OS:12.0, name:iPhone 6s }
{ platform:iOS Simulator, id:78CCA148-1E5C-4FE2-AB0B-B60C097676C7, OS:12.0, name:iPhone 6s Plus }
{ platform:iOS Simulator, id:CC8E3424-09DD-4910-84FB-5903C5EBA92C, OS:12.0, name:iPhone 6s Plus }
{ platform:iOS Simulator, id:B05CCE51-34A4-47FF-8C3C-B6B6B83AABE0, OS:12.0, name:iPhone 7 }
{ platform:iOS Simulator, id:D1F075AA-0EC6-4537-98C5-8E5E195359FD, OS:12.0, name:iPhone 7 }
{ platform:iOS Simulator, id:74A46C58-65F2-4682-81A7-5737AC974582, OS:12.0, name:iPhone 7 Plus }
{ platform:iOS Simulator, id:A4B87FF5-C213-4335-8D12-A798424BD5BE, OS:12.0, name:iPhone 7 Plus }
{ platform:iOS Simulator, id:093A2232-4177-48FC-8488-7999A8E531CF, OS:12.0, name:iPhone 8 }
{ platform:iOS Simulator, id:937E00CC-D2EF-4029-893F-5523FAB787D2, OS:12.0, name:iPhone 8 }
{ platform:iOS Simulator, id:9997130B-4F1A-4B58-BA55-C709FDC28394, OS:12.0, name:iPhone 8 Plus }
{ platform:iOS Simulator, id:DBAC6B7A-8880-4675-A37D-A68D1012C4C7, OS:12.0, name:iPhone 8 Plus }
{ platform:iOS Simulator, id:264C7219-ABEB-438F-B302-7FDFC5682926, OS:12.0, name:iPhone SE }
{ platform:iOS Simulator, id:D37811F2-09E2-49C8-9EF4-25DBBAE9340B, OS:12.0, name:iPhone SE }
{ platform:iOS Simulator, id:73E2CBF3-DC9F-4CE9-B034-E9410D07609A, OS:12.0, name:iPhone X }
{ platform:iOS Simulator, id:CC8B996B-D125-4A43-8C14-8669154F281E, OS:12.0, name:iPhone X }