The output path of Xcode coverage tool has changed.
Xcode9 : DerivedData/{build}/Logs/Test/{testpass}.xcovreport
Xcode10 : DerivedData/{build}/Logs/Test/{testpass}.xcresult/{#}_Test/action.xcovreport
so when running the xcrun xccov view Build/Logs/Test/*.xccovreport it fails with the error: Failed to load coverage report ...