prepared for Swift 5

Motion.podspec

 Pod::Spec.new do |s|
   s.name = 'Motion'
-  s.version = '3.0.0'
-  s.swift_version = '4.2'
+  s.version = '3.1.0'
+  s.swift_version = '5.0'
   s.license = 'MIT'
   s.summary = 'A library used to create beautiful animations and transitions for Apple devices.'
   s.homepage = 'http://cosmicmind.com'

Motion.xcodeproj/project.pbxproj

@@ -329,7 +329,7 @@
 				TargetAttributes = {
 					96C98DD01E424AB000B22906 = {
 						CreatedOnToolsVersion = 8.2.1;
-						LastSwiftMigration = 1000;
+						LastSwiftMigration = 1020;
 						ProvisioningStyle = Automatic;
 					};
 				};
@@ -546,7 +546,7 @@
 				SKIP_INSTALL = YES;
 				SWIFT_OBJC_INTERFACE_HEADER_NAME = "$(SWIFT_MODULE_NAME)-Swift.h";
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Debug;
 		};
@@ -567,7 +567,7 @@
 				PRODUCT_NAME = Motion;
 				SKIP_INSTALL = YES;
 				SWIFT_OBJC_INTERFACE_HEADER_NAME = "$(SWIFT_MODULE_NAME)-Swift.h";
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Release;
 		};

Sources/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>3.0.0</string>
+	<string>3.1.0</string>
 	<key>CFBundleVersion</key>
 	<string>$(CURRENT_PROJECT_VERSION)</string>
 	<key>NSPrincipalClass</key>

Sources/MotionContext.swift

@@ -223,7 +223,7 @@ public extension MotionContext {
           superviewToNoSnapshotSubviewMap[view.superview!] = []
         }
         
-        superviewToNoSnapshotSubviewMap[view.superview!]!.append((view.superview!.subviews.index(of: view)!, view))
+        superviewToNoSnapshotSubviewMap[view.superview!]!.append((view.superview!.subviews.firstIndex(of: view)!, view))
       }
       
       snapshot = view
@@ -322,7 +322,7 @@ public extension MotionContext {
     
     if let pairedView = pairedView(for: view), let pairedSnapshot = viewToSnapshot[pairedView] {
       let siblingViews = pairedView.superview!.subviews
-      let nextSiblings = siblingViews[siblingViews.index(of: pairedView)! + 1..<siblingViews.count]
+      let nextSiblings = siblingViews[siblingViews.firstIndex(of: pairedView)! + 1..<siblingViews.count]
       
       containerView.addSubview(pairedSnapshot)
       containerView.addSubview(snapshot)

Sources/Transition/MotionTransition+UITabBarControllerDelegate.swift

@@ -50,8 +50,8 @@ extension MotionTransition: UITabBarControllerDelegate {
     
     state = .notified
     
-    let fromVCIndex = tabBarController.children.index(of: fromVC)!
-    let toVCIndex = tabBarController.children.index(of: toVC)!
+    let fromVCIndex = tabBarController.children.firstIndex(of: fromVC)!
+    let toVCIndex = tabBarController.children.firstIndex(of: toVC)!
     
     isPresenting = toVCIndex > fromVCIndex
     fromViewController = fromViewController ?? fromVC

Sources/Transition/MotionTransition.swift

@@ -526,7 +526,7 @@ internal extension MotionTransition {
    - Returns: A boolean indicating if the plugin is enabled or not.
    */
   static func isEnabled(plugin: MotionPlugin.Type) -> Bool {
-    return nil != enabledPlugins.index(where: { return $0 == plugin })
+    return nil != enabledPlugins.firstIndex(where: { return $0 == plugin })
   }
   
   /**
@@ -543,7 +543,7 @@ internal extension MotionTransition {
    - Parameter plugin: A MotionPlugin.Type.
    */
   static func disable(plugin: MotionPlugin.Type) {
-    guard let index = enabledPlugins.index(where: { return $0 == plugin }) else {
+    guard let index = enabledPlugins.firstIndex(where: { return $0 == plugin }) else {
       return
     }