Swift4 Only changes and set swift-version to 4

Author: spevans

Foundation/NSURLSession/http/HTTPBodySource.swift

@@ -125,8 +125,13 @@ internal final class _HTTPBodyFileSource {
         var fileSystemRepresentation: UnsafePointer<Int8>! = nil
         fileURL.withUnsafeFileSystemRepresentation {
             fileSystemRepresentation = $0
-        } 
-        self.channel = DispatchIO(type: .stream, path: fileSystemRepresentation, oflag: O_RDONLY, mode: 0, queue: workQueue, cleanupHandler: {_ in })
+        }
+        guard let channel = DispatchIO(type: .stream, path: fileSystemRepresentation,
+                                       oflag: O_RDONLY, mode: 0, queue: workQueue,
+                                       cleanupHandler: {_ in }) else {
+            fatalError("Cant create DispatchIO channel")
+        }
+        self.channel = channel
         self.channel.setLimit(highWater: CFURLSessionMaxWriteSize)
     }
 

lib/phases.py

@@ -173,7 +173,7 @@ def generate(self):
         generated += " -I" + Configuration.current.build_directory.relative()
         swiftflags = TargetConditional.value(self.product.SWIFTCFLAGS)
         # Force building in Swift 3 compatibility mode.
-        swiftflags += " -swift-version 3"
+        swiftflags += " -swift-version 4"
         if swiftflags is not None:
             generated += " " + swiftflags
         return generated
@@ -434,7 +434,7 @@ def generate(self):
         # Note: Fix -swift-version 3 for now.
         return """
 build """ + appName + """: SwiftExecutable """ + swiftSources + self.generate_dependencies(libDependencyName) + """
-    flags = -swift-version 3 -I""" + Configuration.current.build_directory.path_by_appending(self.product.name).relative() + self.product.ROOT_HEADERS_FOLDER_PATH + " -I" + Configuration.current.build_directory.path_by_appending(self.product.name).relative() + " -L" + Configuration.current.build_directory.path_by_appending(self.product.name).relative() + " " + TargetConditional.value(self.product.SWIFTCFLAGS) + """
+    flags = -swift-version 4 -I""" + Configuration.current.build_directory.path_by_appending(self.product.name).relative() + self.product.ROOT_HEADERS_FOLDER_PATH + " -I" + Configuration.current.build_directory.path_by_appending(self.product.name).relative() + " -L" + Configuration.current.build_directory.path_by_appending(self.product.name).relative() + " " + TargetConditional.value(self.product.SWIFTCFLAGS) + """
 build """ + self.executableName + """: phony | """ + appName + """
 """