From e5bdac0e58ea7c842a31f1c59d1236794e3fa9ff Mon Sep 17 00:00:00 2001
From: Artem Novichkov <artem.novichkov@rosberry.com>
Date: Tue, 19 Sep 2017 08:41:31 +0600
Subject: [PATCH 1/2] Refactor with Swift 4 String API

---
 Sources/Files.swift | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/Sources/Files.swift b/Sources/Files.swift
index 845fb9c..c73ea01 100644
--- a/Sources/Files.swift
+++ b/Sources/Files.swift
@@ -167,7 +167,7 @@ public class FileSystem {
             }
 
             let endIndex = name.index(name.endIndex, offsetBy: -`extension`.characters.count - 1)
-            return name.substring(to: endIndex)
+            return String(name[..<endIndex])
         }
         
         /// Any extension that the item has
@@ -341,7 +341,8 @@ public class FileSystem {
         }
 
         do {
-            let name = path.substring(from: path.index(path.startIndex, offsetBy: parentPath.characters.count + 1))
+            let index = path.index(path.startIndex, offsetBy: parentPath.characters.count + 1)
+            let name = String(path[index...])
             return try createFolder(at: parentPath).createFile(named: name, contents: contents)
         } catch {
             throw File.Error.writeFailed
@@ -999,7 +1000,7 @@ private extension FileManager {
         var filledIn = false
 
         while let parentReferenceRange = path.range(of: "../") {
-            let currentFolderPath = path.substring(to: parentReferenceRange.lowerBound)
+            let currentFolderPath = String(path[..<parentReferenceRange.lowerBound])
 
             guard let currentFolder = try? Folder(path: currentFolderPath) else {
                 throw FileSystem.Item.PathError.invalid(path)

From 5f63dab7a16ff69d570ea54d4ec1ded48d8f5f80 Mon Sep 17 00:00:00 2001
From: Artem Novichkov <artem.novichkov@rosberry.com>
Date: Thu, 21 Sep 2017 15:49:08 +0600
Subject: [PATCH 2/2] Update Xcode and Swift version

---
 .swift-version | 2 +-
 .travis.yml    | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/.swift-version b/.swift-version
index 8c50098..5186d07 100644
--- a/.swift-version
+++ b/.swift-version
@@ -1 +1 @@
-3.1
+4.0
diff --git a/.travis.yml b/.travis.yml
index 06f52f3..4859ad9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,6 @@
 os: linux
 language: generic
+osx_image: xcode9
 sudo: required
 dist: trusty
 install: