Update to Xcode 9 recommended and migration to Swift 4 (#96)

* Migrate to Swift 4

* Update project settings to Xcode 9 recommended

* Version Bump to 0.3.0

* Use Swift 4 Codable instead of NSCoding for ListenCache

- Adopt Codable and remove extraneous code
- Add new errors to handle encoding/decoding failures

* Error domain should be static

* Update documentation

* Update Swift version to 4.0

.swift-version

@@ -1 +1 @@
-3.2
+4.0

Bluejay.podspec

@@ -1,12 +1,12 @@
 Pod::Spec.new do |spec|
   spec.name = 'Bluejay'
-  spec.version = '0.2.0'
+  spec.version = '0.3.0'
   spec.license = { type: 'MIT', file: 'LICENSE' }
   spec.homepage = 'https://github.com/steamclock/bluejay'
   spec.authors = { 'Jeremy Chiang' => 'jeremy@steamclock.com' }
   spec.summary = 'Bluejay is a simple Swift framework for building reliable Bluetooth apps.'
   spec.homepage = 'https://github.com/steamclock/bluejay'
-  spec.source = { git: 'https://github.com/steamclock/bluejay.git', tag: 'v0.2.0' }
+  spec.source = { git: 'https://github.com/steamclock/bluejay.git', tag: 'v0.3.0' }
   spec.source_files = 'Bluejay/Bluejay/*.{h,swift}'
   spec.framework = 'SystemConfiguration'
   spec.platform = :ios, '9.3'

Bluejay/Bluejay.xcodeproj/project.pbxproj

@@ -498,17 +498,18 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 0820;
-				LastUpgradeCheck = 0820;
+				LastUpgradeCheck = 0900;
 				ORGANIZATIONNAME = "Steamclock Software";
 				TargetAttributes = {
 					B8C70F741E1C22850006CF58 = {
 						CreatedOnToolsVersion = 8.2.1;
 						DevelopmentTeam = GH868RP95T;
-						LastSwiftMigration = 0820;
+						LastSwiftMigration = 0900;
 						ProvisioningStyle = Automatic;
 					};
 					B8C70F7D1E1C22850006CF58 = {
 						CreatedOnToolsVersion = 8.2.1;
+						LastSwiftMigration = 0900;
 						ProvisioningStyle = Automatic;
 					};
 					B8DEDE601E4A4B5800B2244D = {
@@ -806,15 +807,21 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
 				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
@@ -859,15 +866,21 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
 				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
@@ -916,7 +929,7 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -939,7 +952,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.steamclock.Bluejay;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};
@@ -952,7 +965,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.steamclock.BluejayTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -965,7 +978,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.steamclock.BluejayTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};
@@ -981,7 +994,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.steamclock.BluejayDemo;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -997,7 +1010,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.steamclock.BluejayDemo;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};

Bluejay/Bluejay.xcodeproj/xcshareddata/xcschemes/Bluejay.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0820"
+   LastUpgradeVersion = "0900"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -26,6 +26,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
          <TestableReference
@@ -55,6 +56,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"

Bluejay/Bluejay/Bluejay.swift

@@ -555,7 +555,7 @@ public class Bluejay: NSObject {
 
                     DispatchQueue.main.async {
                         self?.isRunningBackgroundTask = false
-                        completionOnMainThread(.success())
+                        completionOnMainThread(.success(()))
                     }
                 }
                 catch let error as NSError {
@@ -710,7 +710,12 @@ extension Bluejay: CBCentralManagerDelegate {
         }
 
         if central.state == .poweredOn && connectedPeripheral != nil {
-            attemptListenRestoration()
+            do {
+                try requestListenRestoration()
+            }
+            catch {
+                log("Failed to complete listen restoration with error: \(error)")
+            }
         }
 
         if central.state == .poweredOff {
@@ -730,38 +735,45 @@ extension Bluejay: CBCentralManagerDelegate {
     /**
      Examine the listen cache in `UserDefaults` to determine whether there are any listens that might need restoration.
      */
-    private func attemptListenRestoration() {
-        debugPrint("Starting listen restoration.")
+    private func requestListenRestoration() throws {
+        log("Starting listen restoration.")
 
         guard
             let listenCaches = UserDefaults.standard.dictionary(forKey: Constant.listenCaches),
             let cacheData = listenCaches[uuid.uuidString] as? [Data]
         else {
-            debugPrint("No listens to restore.")
+            log("No listens to restore.")
             return
         }
 
+        let decoder = JSONDecoder()
+
         for data in cacheData {
-            let listenCache = (NSKeyedUnarchiver.unarchiveObject(with: data) as? (ListenCache.Coding))!
-                .decoded as! ListenCache
-
-            debugPrint("Listen cache to restore: \(listenCache)")
-
-            let serviceIdentifier = ServiceIdentifier(uuid: listenCache.serviceUUID)
-            let characteristicIdentifier = CharacteristicIdentifier(uuid: listenCache.characteristicUUID, service: serviceIdentifier)
-
-            if let listenRestorer = listenRestorer?.weakReference {
-                if !listenRestorer.willRestoreListen(on: characteristicIdentifier) {
+            do {
+                let listenCache = try decoder.decode(ListenCache.self, from: data)
+
+                log("Listen cache to restore: \(listenCache)")
+
+                let serviceIdentifier = ServiceIdentifier(uuid: listenCache.serviceUUID)
+                let characteristicIdentifier = CharacteristicIdentifier(uuid: listenCache.characteristicUUID, service: serviceIdentifier)
+
+                if let listenRestorer = listenRestorer?.weakReference {
+                    // If true, assume the listen restorable delegate will restore the listen accordingly, otherwise end the listen.
+                    if !listenRestorer.willRestoreListen(on: characteristicIdentifier) {
+                        endListen(to: characteristicIdentifier)
+                    }
+                }
+                else {
+                    // If there is no listen restorable delegate, end the listen as well.
                     endListen(to: characteristicIdentifier)
                 }
             }
-            else {
-                // If there is no listen restorable delegate, end all active listening.
-                endListen(to: characteristicIdentifier)
+            catch {
+                throw BluejayError.listenCacheDecoding(error)
             }
         }
 
-        debugPrint("Listen restoration finished.")
+        log("Listen restoration finished.")
     }
 
     /**
@@ -906,10 +918,10 @@ extension Bluejay: CBCentralManagerDelegate {
 
 }
 
-/// Allows communication between a queue and the Bluejay instance it belongs to.
+/// Allows Bluejay to receive events and delegation from its queue.
 extension Bluejay: QueueObserver {
 
-    /// A way for Bluejay to update the `isConnecting` state with a more accurate timing by waiting to be informed by the queue only when it is about to start running the enqueued `Connection` task.
+    /// Support for the will connect state that CBCentralManagerDelegate does not have.
     func willConnect(to peripheral: CBPeripheral) {
         connectingPeripheral = Peripheral(bluejay: self, cbPeripheral: peripheral)
     }

Bluejay/Bluejay/Error.swift

@@ -8,26 +8,50 @@
 
 import Foundation
 
+/// Errors specific to Bluejay.
 public enum BluejayError {
+    /// Bluetooth is either turned off or unavailable.
     case bluetoothUnavailable
+    /// Bluejay does not support another scanning request if Bluejay is still scanning.
     case multipleScanNotSupported
+    /// Bluejay does not support another connection request if Bluejay is already connected or still connecting.
     case multipleConnectNotSupported
+    /// Bluejay does not support another disconnection request if Bluejay is still disconnecting.
     case multipleDisconnectNotSupported
+    /// A connection request in Bluejay has timed out.
     case connectionTimedOut
+    /// A Bluetooth operation such as, reading or writing, is attempted when Bluejay is not connected to a peripheral.
     case notConnected
+    /// A Bluetooth service is not found.
     case missingService(ServiceIdentifier)
+    /// A Bluetooth characteristic is not found.
     case missingCharacteristic(CharacteristicIdentifier)
+    /// A Bluetooth operation is cancelled.
     case cancelled
+    /// An attempt to listen on a characteristic has timed out.
     case listenTimedOut
+    /// An attempt to read a characteristic has failed.
     case readFailed
+    /// An attempt to write a characteristic has failed.
     case writeFailed
+    /// An attempt to read a value from a characteristic has returned no data unexpectedly.
     case missingData
+    /// An attempt to read a range of data has failed due to incorrect bounds or an unexpected length.
     case dataOutOfBounds(start: Int, length: Int, count: Int)
+    /// An unexpected peripheral is cached and retrieved from CoreBluetooth.
     case unexpectedPeripheral(PeripheralIdentifier)
+    /// iOS will not continue scanning in the background if allow duplicates is turned on.
     case scanningWithAllowDuplicatesInBackgroundNotSupported
+    /// iOS will not continue scanning in the background if no service identifiers are specified.
     case missingServiceIdentifiersInBackground
+    /// Bluejay does not support further Bluetooth operations while a Bluejay background task is still running.
     case backgroundTaskRunning
+    /// Bluejay does not support another Bluejay background task when there is already one that is still running.
     case multipleBackgroundTaskNotSupported
+    /// Bluejay has failed to encode a listen cache.
+    case listenCacheEncoding(Error)
+    /// Bluejay has failed to decode a listen cache.
+    case listenCacheDecoding(Error)
 }
 
 extension BluejayError: LocalizedError {
@@ -71,12 +95,17 @@ extension BluejayError: LocalizedError {
             return "Regular Bluetooth operation is not available when a background task is running. For reading, writing, and listening, please use only the API found in the Synchronized Peripheral provided to you when working inside a background task block."
         case .multipleBackgroundTaskNotSupported:
             return "Multiple background task is not supported."
+        case let .listenCacheEncoding(error):
+            return "Listen cache encoding failed with error: \(error.localizedDescription)"
+        case let .listenCacheDecoding(error):
+            return "Listen cache decoding failed with error: \(error.localizedDescription)"
         }
     }
 }
 
 extension BluejayError: CustomNSError {
-    public var errorDomain: String {
+
+    public static var errorDomain: String {
         return "Bluejay"
     }
 
@@ -101,6 +130,8 @@ extension BluejayError: CustomNSError {
         case .missingServiceIdentifiersInBackground: return 17
         case .backgroundTaskRunning: return 18
         case .multipleBackgroundTaskNotSupported: return 19
+        case .listenCacheEncoding: return 20
+        case .listenCacheDecoding: return 21
         }
     }
 

Bluejay/Bluejay/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>0.2.0</string>
+	<string>0.3.0</string>
 	<key>CFBundleVersion</key>
 	<string>$(CURRENT_PROJECT_VERSION)</string>
 	<key>NSPrincipalClass</key>

Bluejay/Bluejay/Integer+Transferable.swift

@@ -9,7 +9,7 @@
 import Foundation
 
 /// Extension to Int to make it Sendable and Receivable.
-extension Integer {
+extension BinaryInteger {
 
     /// This function is required to conform to `Sendable`, and figures out the size of the `Integer` used by the iOS device.
     public func toBluetoothData() -> Data {