Fix ci script for Xcode 12

scripts/ci.sh

@@ -13,8 +13,8 @@ function xcode_major() {
   echo "$XCODE_MAJOR"
 }
 
-function is_xcode_version_11_plus() {
-  if [[ `xcode_version` -ge 11  ]]; then
+function is_xcode_version_above() {
+  if [[ `xcode_major` -ge $1 ]]; then
     return 0
   else
     return 1
@@ -32,16 +32,18 @@ env NSUnbufferedIO=YES xcodebuild test -project KIF.xcodeproj -derivedDataPath=$
 env NSUnbufferedIO=YES xcodebuild test -project KIF.xcodeproj -scheme KIF -derivedDataPath=${PWD}/build/KIF -destination "platform=iOS Simulator,${SIMULATOR}" | xcpretty -c
 
 # Due to unstable Swift language syntax, this only compiles on Xcode 8+
-if is_xcode_version_11_plus; then
+if is_xcode_version_above 11 ; then
   env NSUnbufferedIO=YES xcodebuild test -project "Documentation/Examples/Testable Swift/Testable Swift.xcodeproj" -scheme "Testable Swift" -derivedDataPath=${PWD}/build/TestableSwift -destination "platform=iOS Simulator,${SIMULATOR}" | xcpretty -c
 fi
 
 env NSUnbufferedIO=YES xcodebuild test -project "Documentation/Examples/Testable/Testable.xcodeproj" -scheme Testable -derivedDataPath=${PWD}/build/Testable -destination "platform=iOS Simulator,${SIMULATOR}" | xcpretty -c
 # For some reason, attempting to run the Calculator tests on Xcode 7 causes a frequent crash in CI
 env NSUnbufferedIO=YES xcodebuild build -project "Documentation/Examples/Calculator/Calculator.xcodeproj" -scheme "Calculator" -derivedDataPath=${PWD}/build/Calculator -destination "platform=iOS Simulator,${SIMULATOR}" | xcpretty -c
 
-carthage build --no-skip-current
-carthage archive KIF
+if ! is_xcode_version_above 12 ; then # see https://github.com/Carthage/Carthage/issues/3019 for Xcode 12 support
+  carthage build --no-skip-current
+  carthage archive KIF
+fi
 
 swift build -Xcc "-isysroot" -Xcc "$(xcrun --sdk iphonesimulator --show-sdk-path)" -Xcc "-target" -Xcc "x86_64-apple-ios$(xcrun --sdk iphonesimulator --show-sdk-version)-simulator"