From 46d982d4dff9124125eb01f0c92a01b1ba226ec2 Mon Sep 17 00:00:00 2001
From: Shane Cowherd <shane.cowherd@bombbomb.com>
Date: Fri, 5 Jan 2018 08:29:49 -0700
Subject: [PATCH] Migrated the Socket.IO 1.X build to Swift 4

---
 .../project.pbxproj                           | 12 +++++++++--
 Source/SocketEngine.swift                     |  7 +++----
 Source/SocketEnginePollable.swift             |  4 ++--
 Source/SocketParsable.swift                   |  4 ++--
 Source/SocketStringReader.swift               | 21 +++++++++----------
 Source/WebSocket.swift                        |  2 +-
 6 files changed, 28 insertions(+), 22 deletions(-)

diff --git a/Socket.IO-Client-Swift.xcodeproj/project.pbxproj b/Socket.IO-Client-Swift.xcodeproj/project.pbxproj
index de5755c..809a0de 100644
--- a/Socket.IO-Client-Swift.xcodeproj/project.pbxproj
+++ b/Socket.IO-Client-Swift.xcodeproj/project.pbxproj
@@ -537,9 +537,11 @@
 				TargetAttributes = {
 					572EF2181B51F16C00EEBB58 = {
 						CreatedOnToolsVersion = 6.4;
+						LastSwiftMigration = 0920;
 					};
 					572EF2231B51F16C00EEBB58 = {
 						CreatedOnToolsVersion = 6.4;
+						LastSwiftMigration = 0920;
 					};
 					572EF2371B51F18A00EEBB58 = {
 						CreatedOnToolsVersion = 6.4;
@@ -886,7 +888,8 @@
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -937,7 +940,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = io.socket.SocketIOClientSwift;
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VALIDATE_PRODUCT = YES;
 				VERSIONING_SYSTEM = "apple-generic";
@@ -993,6 +997,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "io.socket.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = iphoneos;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -1037,6 +1043,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "io.socket.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = iphoneos;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				VALIDATE_PRODUCT = YES;
 			};
 			name = Release;
diff --git a/Source/SocketEngine.swift b/Source/SocketEngine.swift
index c3114d1..8f9a85b 100644
--- a/Source/SocketEngine.swift
+++ b/Source/SocketEngine.swift
@@ -225,8 +225,7 @@ public final class SocketEngine : NSObject, URLSessionDelegate, SocketEnginePoll
 
     private func handleBase64(message: String) {
         // binary in base64 string
-        let noPrefix = message[message.index(message.startIndex, offsetBy: 2)..<message.endIndex]
-
+        let noPrefix = String(message[message.index(message.startIndex, offsetBy: 2)..<message.endIndex])
         if let data = NSData(base64Encoded: noPrefix, options: .ignoreUnknownCharacters) {
             client?.parseEngineBinaryData(data as Data)
         }
@@ -535,13 +534,13 @@ public final class SocketEngine : NSObject, URLSessionDelegate, SocketEnginePoll
 
         switch type {
         case .message:
-            handleMessage(String(fixedString.characters.dropFirst()))
+            handleMessage(String(fixedString.dropFirst()))
         case .noop:
             handleNOOP()
         case .pong:
             handlePong(with: fixedString)
         case .open:
-            handleOpen(openData: String(fixedString.characters.dropFirst()))
+            handleOpen(openData: fixedString)
         case .close:
             handleClose(fixedString)
         default:
diff --git a/Source/SocketEnginePollable.swift b/Source/SocketEnginePollable.swift
index 7862bdf..531deba 100644
--- a/Source/SocketEnginePollable.swift
+++ b/Source/SocketEnginePollable.swift
@@ -94,7 +94,7 @@ extension SocketEnginePollable {
         var postStr = ""
 
         for packet in postWait {
-            let len = packet.characters.count
+            let len = packet.count
 
             postStr += "\(len):\(packet)"
         }
@@ -209,7 +209,7 @@ extension SocketEnginePollable {
     }
 
     func parsePollingMessage(_ str: String) {
-        guard str.characters.count != 1 else { return }
+        guard str.count != 1 else { return }
 
         var reader = SocketStringReader(message: str)
 
diff --git a/Source/SocketParsable.swift b/Source/SocketParsable.swift
index 28b431d..803604e 100644
--- a/Source/SocketParsable.swift
+++ b/Source/SocketParsable.swift
@@ -107,13 +107,13 @@ extension SocketParsable where Self: SocketIOClientSpec {
             }
         }
         
-        var dataArray = message[message.characters.index(reader.currentIndex, offsetBy: 1)..<message.endIndex]
+        var dataArray = message[message.index(reader.currentIndex, offsetBy: 1)..<message.endIndex]
         
         if type == .error && !dataArray.hasPrefix("[") && !dataArray.hasSuffix("]") {
             dataArray = "[" + dataArray + "]"
         }
         
-        switch parseData(dataArray) {
+        switch parseData(String(dataArray)) {
         case let .left(err):
             return .left(err)
         case let .right(data):
diff --git a/Source/SocketStringReader.swift b/Source/SocketStringReader.swift
index 8bdb4d4..07ca875 100644
--- a/Source/SocketStringReader.swift
+++ b/Source/SocketStringReader.swift
@@ -40,34 +40,33 @@ struct SocketStringReader {
     
     @discardableResult
     mutating func advance(by: Int) -> String.Index {
-        currentIndex = message.characters.index(currentIndex, offsetBy: by)
+        currentIndex = message.index(currentIndex, offsetBy: by)
         
         return currentIndex
     }
     
     mutating func read(count: Int) -> String {
-        let readString = message[currentIndex..<message.characters.index(currentIndex, offsetBy: count)]
-        
+        let readString = message[currentIndex..<message.index(currentIndex, offsetBy: count)]
         advance(by: count)
         
-        return readString
+        return String(readString)
     }
     
     mutating func readUntilOccurence(of string: String) -> String {
-        let substring = message[currentIndex..<message.endIndex]
+        let substring = message.utf16[currentIndex...]
         
-        guard let foundRange = substring.range(of: string) else {
-            currentIndex = message.endIndex
+        guard let foundIndex = substring.index(of: string.utf16.first!) else {
+            currentIndex = message.utf16.endIndex
             
-            return substring
+            return String(substring)!
         }
         
-        advance(by: message.characters.distance(from: message.characters.startIndex, to: foundRange.lowerBound) + 1)
+        advance(by: substring.distance(from: substring.startIndex, to: foundIndex) + 1)
         
-        return substring.substring(to: foundRange.lowerBound)
+        return String(substring[substring.startIndex..<foundIndex])!
     }
     
     mutating func readUntilEnd() -> String {
-        return read(count: message.characters.distance(from: currentIndex, to: message.endIndex))
+        return read(count: message.distance(from: currentIndex, to: message.endIndex))
     }
 }
diff --git a/Source/WebSocket.swift b/Source/WebSocket.swift
index 34152af..f57ec3d 100644
--- a/Source/WebSocket.swift
+++ b/Source/WebSocket.swift
@@ -115,7 +115,7 @@ open class WebSocket : NSObject, StreamDelegate {
     
     
     // MARK: - Block based API.
-    public var onConnect: ((Void) -> Void)?
+    public var onConnect: (() -> Void)?
     public var onDisconnect: ((NSError?) -> Void)?
     public var onText: ((String) -> Void)?
     public var onData: ((Data) -> Void)?