Merge pull request #22 from mxcl/files()

Entry.files defaults to all files

.gitignore

@@ -1,3 +1,5 @@
 .DS_Store
 /.build
 /*.xcodeproj
+/build
+/docs

.travis.yml

@@ -0,0 +1,128 @@
+# only run for: merge commits, releases and pull-requests
+if: type != push OR branch = master OR branch =~ /^\d+\.\d+(\.\d+)?(-\S*)?$/
+
+stages:
+  - name: pretest
+  - name: test
+  - name: deploy
+    if: branch =~ ^\d+\.\d+\.\d+$
+
+os: osx
+language: swift
+osx_image: xcode10.1
+xcode_project: Path.swift.xcodeproj
+xcode_scheme: Path.swift-Package
+  
+jobs:
+  include:
+    - script: swift test --parallel
+      name: macOS / Swift 4.2.1
+
+    - &xcodebuild
+      before_install: swift package generate-xcodeproj
+      xcode_destination: platform=iOS Simulator,OS=latest,name=iPhone XS
+      name: iOS / Swift 4.2.1
+    - <<: *xcodebuild
+      xcode_destination: platform=tvOS Simulator,OS=latest,name=Apple TV
+      name: tvOS / Swift 4.2.1
+    - <<: *xcodebuild
+      name: watchOS / Swift 4.2.1
+      script: |
+        set -o pipefail
+        xcodebuild \
+          -project Path.swift.xcodeproj \
+          -scheme Path.swift-Package \
+          -destination 'platform=watchOS Simulator,OS=latest,name=Apple Watch Series 4 - 40mm' \
+          build | xcpretty
+
+    - &linux
+      env: SWIFT_VERSION=4.2.1
+      os: linux
+      name: Linux / Swift 4.2.1
+      language: generic
+      dist: trusty
+      sudo: false
+      install: eval "$(curl -sL https://swiftenv.fuller.li/install.sh)"
+      script: swift test --parallel
+      
+    - <<: *linux
+      env: SWIFT_VERSION='5.0-DEVELOPMENT-SNAPSHOT-2019-01-22-a'
+      name: Linux / Swift 5.0.0-dev (2019-01-22)
+      
+    - stage: pretest
+      name: Check Linux tests are sync’d
+      install: swift test --generate-linuxmain
+      script: git diff --exit-code
+
+    - stage: deploy
+      name: Jazzy
+      before_install: |
+        cat <<\ \ EOF> .jazzy.yaml
+        module: Path
+        module_version: TRAVIS_TAG
+        custom_categories:
+          - name: Path
+            children:
+              - Path
+              - /(_:_:)
+        xcodebuild_arguments:
+          - UseModernBuildSystem=NO
+        output: output
+        github_url: https://github.com/mxcl/Path.swift
+        exclude:
+          - Sources/Path+StringConvertibles.swift
+        EOF
+        sed -i '' "s/TRAVIS_TAG/$TRAVIS_TAG/" .jazzy.yaml
+      # ^^ this weirdness because Travis multiline YAML is broken and inserts
+      # two spaces in front of the output which means we need a prefixed
+      # delimiter which also weirdly stops bash from doing variable substitution
+      install: gem install jazzy
+      before_script: swift package generate-xcodeproj
+      script: jazzy
+      deploy:
+        provider: pages
+        skip-cleanup: true
+        github-token: $GITHUB_TOKEN
+        local-dir: output
+        on:
+          tags: true
+
+    - name: CocoaPods
+      before_install: |
+        export DESCRIPTION=$(swift - <<\ \ EOF
+          import Foundation
+          struct Response: Decodable { let description: String }
+          let token = ProcessInfo.processInfo.environment["GITHUB_TOKEN"]!
+          let url = URL(string: "https://api.github.com/repos/mxcl/Path.swift")!
+          var rq = URLRequest(url: url)
+          rq.setValue("token \(token)", forHTTPHeaderField: "Authorization")
+          let semaphore = DispatchSemaphore(value: 0)
+          var data: Data!
+          URLSession.shared.dataTask(with: rq) { d, _, _ in
+              data = d
+              semaphore.signal()
+          }.resume()
+          semaphore.wait()
+          let rsp = try JSONDecoder().decode(Response.self, from: data)
+          print(rsp.description, terminator: "")
+        EOF)
+        cat <<\ \ EOF> Path.swift.podspec
+        Pod::Spec.new do |s|
+          s.name = 'Path.swift'
+          s.version = ENV['TRAVIS_TAG']
+          s.summary = ENV['DESCRIPTION']
+          s.homepage = 'https://github.com/mxcl/Path.swift'
+          s.license = { :type => 'Unlicense', :file => 'LICENSE.md' }
+          s.author = { 'mxcl' => 'mxcl@me.com' }
+          s.source = { :git => 'https://github.com/mxcl/Path.swift.git', :tag => s.version.to_s }
+          s.social_media_url = 'https://twitter.com/mxcl'
+          s.osx.deployment_target = '10.10'
+          s.ios.deployment_target = '8.0'
+          s.tvos.deployment_target = '10.0'
+          s.watchos.deployment_target = '3.0'
+          s.source_files = 'Sources/*'
+          s.swift_version = '4.2'
+        end
+        EOF
+      install: gem install cocoapods --pre
+      script: pod trunk push

Package@swift-5.0.swift

@@ -0,0 +1,20 @@
+// swift-tools-version:5.0
+import PackageDescription
+
+let pkg = Package(
+    name: "Path.swift",
+    products: [
+        .library(name: "Path", targets: ["Path"]),
+    ],
+    targets: [
+        .target(name: "Path", path: "Sources"),
+        .testTarget(name: "PathTests", dependencies: ["Path"]),
+    ]
+)
+
+pkg.platforms = [
+   .macOS(.v10_10), .iOS(.v8), .tvOS(.v10), .watchOS(.v3)
+]
+pkg.swiftLanguageVersions = [
+    .v4_2, .v5
+]

README.md

@@ -1,9 +1,11 @@
-# Path.swift
+# Path.swift ![badge-platforms] ![badge-languages][] [![Build Status](https://travis-ci.com/mxcl/Path.swift.svg)](https://travis-ci.com/mxcl/Path.swift)
 
-A file-system pathing library focused on developer experience and robust
-end‐results.
+A file-system pathing library focused on developer experience and robust end
+results.
 
 ```swift
+import Path
+
 // convenient static members
 let home = Path.home
 
@@ -13,31 +15,50 @@ let docs = Path.home/"Documents"
 // paths are *always* absolute thus avoiding common bugs
 let path = Path(userInput) ?? Path.cwd/userInput
 
-// chainable syntax so you have less boilerplate
-try Path.home.join("foo").mkpath().join("bar").chmod(0o555)
+// elegant, chainable syntax
+try Path.home.join("foo").mkdir().join("bar").touch().chmod(0o555)
+
+// sensible considerations
+try Path.home.join("bar").mkdir()
+try Path.home.join("bar").mkdir()  // doesn’t throw ∵ we already have the desired result
 
 // easy file-management
-try Path.root.join("foo").copy(to: Path.root.join("bar"))
+let bar = try Path.root.join("foo").copy(to: Path.root/"bar")
+print(bar)         // => /bar
+print(bar.isFile)  // => true
 
-// careful API to avoid common bugs
-try Path.root.join("foo").copy(into: Path.root.mkdir("bar"))
-// ^^ other libraries would make the `to:` form handle both these cases
-// but that can easily lead to bugs where you accidentally write files that
-// were meant to be directory destinations
+// careful API considerations so as to avoid common bugs
+let foo = try Path.root.join("foo").copy(into: Path.root.join("bar").mkdir())
+print(foo)         // => /bar/foo
+print(foo.isFile)  // => true
+
+// we support dynamic members (_use_sparingly_):
+let prefs = Path.home.Library.Preferences  // => /Users/mxcl/Library/Preferences
+
+// a practical example: installing a helper executable
+try Bundle.resources.join("helper").copy(into: Path.home.join(".local/bin").mkdir(.p)).chmod(0o500)
 ```
 
-Paths are just string representations, there *may not* be a real file there.
+We emphasize safety and correctness, just like Swift, and also (again like
+Swift), we provide a thoughtful and comprehensive (yet concise) API.
 
 # Support mxcl
 
 Hi, I’m Max Howell and I have written a lot of open source software, and
-probably you already use some of it (Homebrew anyone?). Please help me so I
-can continue to make tools and software you need and love. I appreciate it x.
+probably you already use some of it (Homebrew anyone?). I work full-time on
+open source and it’s hard; currently I earn *less* than minimum wage. Please
+help me continue my work, I appreciate it x
 
 <a href="https://www.patreon.com/mxcl">
 	<img src="https://c5.patreon.com/external/logo/become_a_patron_button@2x.png" width="160">
 </a>
 
+[Other donation/tipping options](http://mxcl.github.io/donate/)
+
+# Handbook
+
+Our [online API documentation] is automatically updated for new releases.
+
 ## Codable
 
 We support `Codable` as you would expect:
@@ -77,6 +98,19 @@ decoder.userInfo[.relativePath] = Path.home
 decoder.decode(from: data)
 ```
 
+## Dynamic members
+
+We support `@dynamicMemberLookup`:
+
+```swift
+let ls = Path.root.usr.bin.ls  // => /usr/bin/ls
+```
+
+This is less commonly useful than you would think, hence our documentation
+does not use it. Usually you are joining variables or other `String` arguments 
+or trying to describe files (and files usually have extensions). However when
+you need it, it’s *lovely*.
+
 ## Initializing from user-input
 
 The `Path` initializer returns `nil` unless fed an absolute path; thus to
@@ -90,6 +124,9 @@ This is explicit, not hiding anything that code-review may miss and preventing
 common bugs like accidentally creating `Path` objects from strings you did not
 expect to be relative.
 
+Our initializer is nameless to be consistent with the equivalent operation for
+converting strings to `Int`, `Float` etc. in the standard library.
+
 ## Extensions
 
 We have some extensions to Apple APIs:
@@ -102,8 +139,7 @@ bashProfile += "\n\nfoo"
 
 try bashProfile.write(to: Path.home/".bash_profile")
 
-try Bundle.main.resources!.join("foo").copy(to: .home)
-// ^^ `-> Path?` because the underlying `Bundle` function is `-> String?`
+try Bundle.main.resources.join("foo").copy(to: .home)
 ```
 
 ## Directory listings
@@ -112,34 +148,102 @@ We provide `ls()`, called because it behaves like the Terminal `ls` function,
 the name thus implies its behavior, ie. that it is not recursive.
 
 ```swift
-for path in Path.home.ls() {
-    print(path.path)
-    print(path.kind)  // .directory or .file
+for entry in Path.home.ls() {
+    print(entry.path)
+    print(entry.kind)  // .directory or .file
 }
 
-for path in Path.home.ls() where path.kind == .file {
+for entry in Path.home.ls() where entry.kind == .file {
     //…
 }
 
-for path in Path.home.ls() where path.mtime > yesterday {
+for entry in Path.home.ls() where entry.path.mtime > yesterday {
     //…
 }
 
-let dirs = Path.home.ls().directories().filter {
-    //…
-}
+let dirs = Path.home.ls().directories
+
+let files = Path.home.ls().files
 
 let swiftFiles = Path.home.ls().files(withExtension: "swift")
 ```
 
-# Installation
+# Rules & Caveats
 
-SwiftPM only:
+Paths are just string representations, there *might not* be a real file there.
 
 ```swift
-package.append(.package(url: "https://github.com/mxcl/Path.swift", from: "0.0.0"))
+Path.home/"b"      // => /Users/mxcl/b
+
+// joining multiple strings works as you’d expect
+Path.home/"b"/"c"  // => /Users/mxcl/b/c
+
+// joining multiple parts at a time is fine
+Path.home/"b/c"    // => /Users/mxcl/b/c
+
+// joining with absolute paths omits prefixed slash
+Path.home/"/b"     // => /Users/mxcl/b
+
+// of course, feel free to join variables:
+let b = "b"
+let c = "c"
+Path.home/b/c      // => /Users/mxcl/b/c
+
+// tilde is not special here
+Path.root/"~b"     // => /~b
+Path.root/"~/b"    // => /~/b
+
+// but is here
+Path("~/foo")!     // => /Users/mxcl/foo
+
+// this does not work though
+Path("~foo")       // => nil
 ```
 
+*Path.swift* has the general policty that if the desired end result preexists,
+then it’s a noop:
+
+* If you try to delete a file, but the file doesn't exist, we do nothing.
+* If you try to make a directory and it already exists, we do nothing.
+
+However notably if you try to copy or move a file with specifying `overwrite`
+and the file already exists at the destination and is identical, we don’t check
+for that as the check was deemed too expensive to be worthwhile.
+
+# Installation
+
+SwiftPM:
+
+```swift
+package.append(.package(url: "https://github.com/mxcl/Path.swift", from: "0.5.0"))
+```
+
+CocoaPods:
+
+```ruby
+pod 'Path.swift', '~> 0.5'
+```
+
+Carthage:
+
+> Waiting on: [@Carthage#1945](https://github.com/Carthage/Carthage/pull/1945).
+
+## Please note
+
+We are pre 1.0, thus we can change the API as we like, and we will (to the
+pursuit of getting it *right*)! We will tag 1.0 as soon as possible.
+
 ### Get push notifications for new releases
 
 https://codebasesaga.com/canopy/
+
+# Alternatives
+
+* [PathKit](https://github.com/kylef/PathKit) by Kyle Fuller
+* [Files](https://github.com/JohnSundell/Files) by John Sundell
+* [Utility](https://github.com/apple/swift-package-manager) by Apple
+
+
+[badge-platforms]: https://img.shields.io/badge/platforms-macOS%20%7C%20Linux%20%7C%20iOS%20%7C%20tvOS%20%7C%20watchOS-lightgrey.svg
+[badge-languages]: https://img.shields.io/badge/swift-4.2%20%7C%205.0-orange.svg
+[online API documentation]: https://mxcl.github.io/Path.swift/Structs/Path.html

Sources/Extensions.swift

@@ -1,22 +1,51 @@
 import Foundation
 
+/// Extensions on Foundation’s `Bundle` so you get `Path` rather than `String` or `URL`.
 public extension Bundle {
+    /// Returns the path for requested resource in this bundle.
     func path(forResource: String, ofType: String?) -> Path? {
         let f: (String?, String?) -> String? = path(forResource:ofType:)
         let str = f(forResource, ofType)
         return str.flatMap(Path.init)
     }
 
-    public var sharedFrameworks: Path? {
-        return sharedFrameworksPath.flatMap(Path.init)
+    /// Returns the path for the shared-frameworks directory in this bundle.
+    var sharedFrameworks: Path {
+        var `default`: Path {
+          #if os(macOS)
+            return path.join("Contents/Frameworks")
+          #elseif os(Linux)
+            return path.join("lib")
+          #else
+            return path.join("Frameworks")
+          #endif
+        }
+        return sharedFrameworksPath.flatMap(Path.init) ?? `default`
     }
 
-    public var resources: Path? {
-        return resourcePath.flatMap(Path.init)
+    /// Returns the path for the resources directory in this bundle.
+    var resources: Path {
+        var `default`: Path {
+          #if os(macOS)
+            return path.join("Contents/Resources")
+          #elseif os(Linux)
+            return path.join("share")
+          #else
+            return path
+          #endif
+        }
+        return resourcePath.flatMap(Path.init) ?? `default`
+    }
+
+    /// Returns the path for this bundle.
+    var path: Path {
+        return Path(string: bundlePath)
     }
 }
 
+/// Extensions on `String` that work with `Path` rather than `String` or `URL`
 public extension String {
+    /// Initializes this `String` with the contents of the provided path.
     @inlinable
     init(contentsOf path: Path) throws {
         try self.init(contentsOfFile: path.string)
@@ -31,7 +60,9 @@ public extension String {
     }
 }
 
+/// Extensions on `Data` that work with `Path` rather than `String` or `URL`
 public extension Data {
+    /// Initializes this `Data` with the contents of the provided path.
     @inlinable
     init(contentsOf path: Path) throws {
         try self.init(contentsOf: path.url)
@@ -43,7 +74,11 @@ public extension Data {
     func write(to: Path, atomically: Bool = false) throws -> Path {
         let opts: NSData.WritingOptions
         if atomically {
+        #if !os(Linux)
             opts = .atomicWrite
+        #else
+            opts = .atomic
+        #endif
         } else {
             opts = []
         }
@@ -51,3 +86,24 @@ public extension Data {
         return to
     }
 }
+
+/// Extensions on `FileHandle` that work with `Path` rather than `String` or `URL`
+public extension FileHandle {
+    /// Initializes this `FileHandle` for reading at the location of the provided path.
+    @inlinable
+    convenience init(forReadingAt path: Path) throws {
+        try self.init(forReadingFrom: path.url)
+    }
+    
+    /// Initializes this `FileHandle` for writing at the location of the provided path.
+    @inlinable
+    convenience init(forWritingAt path: Path) throws {
+        try self.init(forWritingTo: path.url)
+    }
+    
+    /// Initializes this `FileHandle` for reading and writing at the location of the provided path.
+    @inlinable
+    convenience init(forUpdatingAt path: Path) throws {
+        try self.init(forUpdating: path.url)
+    }
+}

Sources/Path+Attributes.swift

@@ -1,10 +1,52 @@
 import Foundation
 
 public extension Path {
+    //MARK: Filesystem Attributes
+
+    /**
+     Returns the creation-time of the file.
+     - Note: Returns UNIX-time-zero if there is no creation-time, this should only happen if the file doesn’t exist.
+     */
+    var ctime: Date {
+        do {
+            let attrs = try FileManager.default.attributesOfItem(atPath: string)
+            return attrs[.creationDate] as? Date ?? Date(timeIntervalSince1970: 0)
+        } catch {
+            //TODO log error
+            return Date(timeIntervalSince1970: 0)
+        }
+    }
+
+    /**
+     Returns the modification-time of the file.
+     - Note: Returns the creation time if there is no modification time.
+     - Note: Returns UNIX-time-zero if neither are available, this should only happen if the file doesn’t exist.
+     */
+    var mtime: Date {
+        do {
+            let attrs = try FileManager.default.attributesOfItem(atPath: string)
+            return attrs[.modificationDate] as? Date ?? ctime
+        } catch {
+            //TODO log error
+            return Date(timeIntervalSince1970: 0)
+        }
+    }
+
+    /**
+     Sets the file’s attributes using UNIX octal notation.
+
+         Path.home.join("foo").chmod(0o555)
+     */
+    @discardableResult
+    func chmod(_ octal: Int) throws -> Path {
+        try FileManager.default.setAttributes([.posixPermissions: octal], ofItemAtPath: string)
+        return self
+    }
+    
     /// - Note: If file is already locked, does nothing
     /// - Note: If file doesn’t exist, throws
     @discardableResult
-    public func lock() throws -> Path {
+    func lock() throws -> Path {
         var attrs = try FileManager.default.attributesOfItem(atPath: string)
         let b = attrs[.immutable] as? Bool ?? false
         if !b {
@@ -17,7 +59,7 @@ public extension Path {
     /// - Note: If file isn‘t locked, does nothing
     /// - Note: If file doesn’t exist, does nothing
     @discardableResult
-    public func unlock() throws -> Path {
+    func unlock() throws -> Path {
         var attrs: [FileAttributeKey: Any]
         do {
             attrs = try FileManager.default.attributesOfItem(atPath: string)
@@ -31,26 +73,4 @@ public extension Path {
         }
         return self
     }
-
-    /**
-     Sets the file’s attributes using UNIX octal notation.
-
-         Path.home.join("foo").chmod(0o555)
-     */
-    @discardableResult
-    public func chmod(_ octal: Int) throws -> Path {
-        try FileManager.default.setAttributes([.posixPermissions: octal], ofItemAtPath: string)
-        return self
-    }
-
-    /// - Returns: modification-time or creation-time if none
-    public var mtime: Date {
-        do {
-            let attrs = try FileManager.default.attributesOfItem(atPath: string)
-            return attrs[.modificationDate] as? Date ?? attrs[.creationDate] as? Date ?? Date()
-        } catch {
-            //TODO print(error)
-            return Date()
-        }
-    }
 }

Sources/Path+Codable.swift

@@ -1,10 +1,31 @@
 import Foundation
 
+/**
+ Provided for relative-path coding. See the instructions in our
+ [README](https://github.com/mxcl/Path.swift/#codable).
+*/
 public extension CodingUserInfoKey {
+    /**
+     If set on an `Encoder`’s `userInfo` all paths are encoded relative to this path.
+
+     For example:
+
+         let encoder = JSONEncoder()
+         encoder.userInfo[.relativePath] = Path.home
+         encoder.encode([Path.home, Path.home/"foo"])
+
+     - Remark: See the [README](https://github.com/mxcl/Path.swift/#codable) for more information.
+    */
     static let relativePath = CodingUserInfoKey(rawValue: "dev.mxcl.Path.relative")!
 }
 
-extension Path: Codable {
+/**
+ Provided for relative-path coding. See the instructions in our
+ [README](https://github.com/mxcl/Path.swift/#codable).
+*/
+extension Path: Codable {    
+    /// - SeeAlso: `CodingUserInfoKey.relativePath`
+    /// :nodoc:
     public init(from decoder: Decoder) throws {
         let value = try decoder.singleValueContainer().decode(String.self)
         if value.hasPrefix("/") {
@@ -17,6 +38,8 @@ extension Path: Codable {
         }
     }
 
+    /// - SeeAlso: `CodingUserInfoKey.relativePath`
+    /// :nodoc:
     public func encode(to encoder: Encoder) throws {
         var container = encoder.singleValueContainer()
         if let root = encoder.userInfo[.relativePath] as? Path {

Sources/Path+CommonDirectories.swift

@@ -0,0 +1,92 @@
+import Foundation
+
+extension Path {
+    //MARK: Common Directories
+    
+    /// Returns a `Path` containing `FileManager.default.currentDirectoryPath`.
+    public static var cwd: Path {
+        return Path(string: FileManager.default.currentDirectoryPath)
+    }
+
+    /// Returns a `Path` representing the root path.
+    public static var root: Path {
+        return Path(string: "/")
+    }
+
+    /// Returns a `Path` representing the user’s home directory
+    public static var home: Path {
+        let string: String
+      #if os(macOS)
+        if #available(OSX 10.12, *) {
+            string = FileManager.default.homeDirectoryForCurrentUser.path
+        } else {
+            string = NSHomeDirectory()
+        }
+      #else
+        string = NSHomeDirectory()
+      #endif
+        return Path(string: string)
+    }
+
+    /// Helper to allow search path and domain mask to be passed in.
+    private static func path(for searchPath: FileManager.SearchPathDirectory) -> Path {
+    #if os(Linux)
+        // the urls(for:in:) function is not implemented on Linux
+        //TODO strictly we should first try to use the provided binary tool
+
+        let foo = { ProcessInfo.processInfo.environment[$0].flatMap(Path.init) ?? $1 }
+
+        switch searchPath {
+        case .documentDirectory:
+            return Path.home/"Documents"
+        case .applicationSupportDirectory:
+            return foo("XDG_DATA_HOME", Path.home/".local/share")
+        case .cachesDirectory:
+            return foo("XDG_CACHE_HOME", Path.home/".cache")
+        default:
+            fatalError()
+        }
+    #else    
+        guard let pathString = FileManager.default.urls(for: searchPath, in: .userDomainMask).first?.path else {
+            switch searchPath {
+            case .documentDirectory:
+                return Path.home/"Documents"
+            case .applicationSupportDirectory:
+                return Path.home/"Library/Application Support"
+            case .cachesDirectory:
+                return Path.home/"Library/Caches"
+            default:
+                fatalError()
+            }
+        }
+        return Path(string: pathString)
+    #endif
+    }
+
+    /**
+     The root for user documents.
+     - Note: There is no standard location for documents on Linux, thus we return `~/Documents`.
+     - Note: You should create a subdirectory before creating any files.
+     */
+    public static var documents: Path {
+        return path(for: .documentDirectory)
+    }
+
+    /**
+     The root for cache files.
+     - Note: On Linux this is `XDG_CACHE_HOME`.
+     - Note: You should create a subdirectory before creating any files.
+     */
+    public static var caches: Path {
+        return path(for: .cachesDirectory)
+    }
+
+    /**
+     For data that supports your running application.
+     - Note: On Linux is `XDG_DATA_HOME`.
+     - Note: You should create a subdirectory before creating any files.
+     */
+    public static var applicationSupport: Path {
+        return path(for: .applicationSupportDirectory)
+    }
+}

Sources/Path+FileManager.swift

@@ -1,17 +1,28 @@
 import Foundation
 
 public extension Path {
+    //MARK: File Management
+    
     /**
      Copies a file.
+
+         try Path.root.join("bar").copy(to: Path.home/"foo")
+         // => "/Users/mxcl/foo"
+
      - Note: `throws` if `to` is a directory.
      - Parameter to: Destination filename.
-     - Parameter overwrite: If true overwrites any file that already exists at `to`.
+     - Parameter overwrite: If `true` and both `self` and `to` are files, overwrites `to`.
+     - Note: If either `self` or `to are directories, `overwrite` is ignored.
+     - Note: Throws if `overwrite` is `false` yet `to` is *already* identical to
+      `self` because even though *Path.swift’s* policy is to noop if the desired
+       end result preexists, checking for this condition is too expensive a
+       trade-off.
      - Returns: `to` to allow chaining
-     - SeeAlso: copy(into:overwrite:)
+     - SeeAlso: `copy(into:overwrite:)`
      */
     @discardableResult
-    public func copy(to: Path, overwrite: Bool = false) throws -> Path {
-        if overwrite, to.exists {
+    func copy(to: Path, overwrite: Bool = false) throws -> Path {
+        if overwrite, to.isFile, isFile {
             try FileManager.default.removeItem(at: to.url)
         }
         try FileManager.default.copyItem(atPath: string, toPath: to.string)
@@ -21,89 +32,149 @@ public extension Path {
     /**
      Copies a file into a directory
 
+         try Path.root.join("bar").copy(into: .home)
+         // => "/Users/mxcl/bar"
+
+         // Create ~/.local/bin, copy `ls` there and make the new copy executable
+         try Path.root.join("bin/ls").copy(into: Path.home.join(".local/bin").mkdir(.p)).chmod(0o500)
+
      If the destination does not exist, this function creates the directory first.
 
-     - Note: `throws` if `into` is a file.
      - Parameter into: Destination directory
      - Parameter overwrite: If true overwrites any file that already exists at `into`.
      - Returns: The `Path` of the newly copied file.
-     - SeeAlso: copy(into:overwrite:)
+     - Note: `throws` if `into` is a file.
+     - Note: Throws if `overwrite` is `false` yet `to` is *already* identical to
+      `self` because even though *Path.swift’s* policy is to noop if the desired
+       end result preexists, checking for this condition is too expensive a
+       trade-off.
+     - SeeAlso: `copy(into:overwrite:)`
      */
     @discardableResult
-    public func copy(into: Path, overwrite: Bool = false) throws -> Path {
+    func copy(into: Path, overwrite: Bool = false) throws -> Path {
         if !into.exists {
             try FileManager.default.createDirectory(at: url, withIntermediateDirectories: true)
-        } else if overwrite, !into.isDirectory {
-            try into.delete()
         }
         let rv = into/basename()
+        if overwrite, rv.isFile {
+            try rv.delete()
+        }
+    #if os(Linux)
+    #if swift(>=5.1)
+        // check if fixed
+    #else
+        if !overwrite, rv.isFile {
+            throw CocoaError.error(.fileWriteFileExists)
+        }
+    #endif
+    #endif
         try FileManager.default.copyItem(at: url, to: rv.url)
         return rv
     }
 
+    /**
+     Moves a file.
+
+         try Path.root.join("bar").move(to: Path.home/"foo")
+         // => "/Users/mxcl/foo"
+
+     - Parameter to: Destination filename.
+     - Parameter overwrite: If true overwrites any file that already exists at `to`.
+     - Returns: `to` to allow chaining
+     - Note: `throws` if `to` is a directory.
+     - Note: Throws if `overwrite` is `false` yet `to` is *already* identical to
+       `self` because even though *Path.swift’s* policy is to noop if the desired
+       end result preexists, checking for this condition is too expensive a
+       trade-off.
+     - SeeAlso: move(into:overwrite:)
+     */
     @discardableResult
-    public func move(into: Path) throws -> Path {
+    func move(to: Path, overwrite: Bool = false) throws -> Path {
+        if overwrite, to.exists {
+            try FileManager.default.removeItem(at: to.url)
+        }
+        try FileManager.default.moveItem(at: url, to: to.url)
+        return to
+    }
+
+    /**
+     Moves a file into a directory
+
+         try Path.root.join("bar").move(into: .home)
+         // => "/Users/mxcl/bar"
+
+     If the destination does not exist, this function creates the directory first.
+
+     - Parameter into: Destination directory
+     - Parameter overwrite: If true *overwrites* any file that already exists at `into`.
+     - Note: `throws` if `into` is a file.
+     - Returns: The `Path` of destination filename.
+     - SeeAlso: move(into:overwrite:)
+     */
+    @discardableResult
+    func move(into: Path) throws -> Path {
         if !into.exists {
-            try into.mkpath()
+            try into.mkdir(.p)
         } else if !into.isDirectory {
             throw CocoaError.error(.fileWriteFileExists)
         }
-        try FileManager.default.moveItem(at: url, to: into.join(basename()).url)
-        return self
+        let rv = into/basename()
+        try FileManager.default.moveItem(at: url, to: rv.url)
+        return rv
     }
 
+    /**
+     Deletes the path, recursively if a directory.
+     - Note: noop: if the path doesn’t exist
+     ∵ *Path.swift* doesn’t error if desired end result preexists.
+    */
     @inlinable
-    public func delete() throws {
-        try FileManager.default.removeItem(at: url)
+    func delete() throws {
+        if exists {
+            try FileManager.default.removeItem(at: url)
+        }
     }
 
+    /**
+     Creates an empty file at this path.
+     - Returns: `self` to allow chaining.
+     */
     @inlinable
     @discardableResult
     func touch() throws -> Path {
         return try "".write(to: self)
     }
 
-    @inlinable
+    /**
+     Creates the directory at this path.
+     - Parameter options: Specify `mkdir(.p)` to create intermediary directories.
+     - Note: We do not error if the directory already exists (even without `.p`)
+       because *Path.swift* noops if the desired end result preexists.
+     - Returns: `self` to allow chaining.
+     */
     @discardableResult
-    public func mkdir() throws -> Path {
+    func mkdir(_ options: MakeDirectoryOptions? = nil) throws -> Path {
         do {
-            try FileManager.default.createDirectory(at: url, withIntermediateDirectories: false, attributes: nil)
+            let wid = options == .p
+            try FileManager.default.createDirectory(at: self.url, withIntermediateDirectories: wid, attributes: nil)
         } catch CocoaError.Code.fileWriteFileExists {
-            // noop
+            //noop (fails to trigger on Linux)
+        } catch {
+        #if os(Linux)
+            let error = error as NSError
+            guard error.domain == NSCocoaErrorDomain, error.code == CocoaError.Code.fileWriteFileExists.rawValue else {
+                throw error
+            }
+        #else
+            throw error
+        #endif
         }
         return self
     }
-
-    @inlinable
-    @discardableResult
-    public func mkpath() throws -> Path {
-        do {
-            try FileManager.default.createDirectory(at: url, withIntermediateDirectories: true, attributes: nil)
-        } catch CocoaError.Code.fileWriteFileExists {
-            // noop
-        }
-        return self
-    }
-
-    /// - Note: If file doesn’t exist, creates file
-    /// - Note: If file is not writable, makes writable first, resetting permissions after the write
-    @discardableResult
-    public func replaceContents(with contents: String, atomically: Bool = false, encoding: String.Encoding = .utf8) throws -> Path {
-        let resetPerms: Int?
-        if exists, !isWritable {
-            resetPerms = try FileManager.default.attributesOfItem(atPath: string)[.posixPermissions] as? Int
-            let perms = resetPerms ?? 0o777
-            try chmod(perms | 0o200)
-        } else {
-            resetPerms = nil
-        }
-
-        defer {
-            _ = try? resetPerms.map(self.chmod)
-        }
-
-        try contents.write(to: self)
-
-        return self
-    }
+}
+
+/// Options for `Path.mkdir(_:)`
+public enum MakeDirectoryOptions {
+    /// Creates intermediary directories; works the same as `mkdir -p`.
+    case p
 }

Sources/Path+StringConvertibles.swift

@@ -1,20 +1,14 @@
 import class Foundation.NSString
 
-extension Path: LosslessStringConvertible {
-    /// Returns `nil` unless fed an absolute path
-    public init?(_ description: String) {
-        guard description.starts(with: "/") || description.starts(with: "~/") else { return nil }
-        self.init(string: (description as NSString).standardizingPath)
-    }
-}
-
-extension Path: CustomStringConvertible {
+extension Path: CustomStringConvertible {    
+    /// Returns `Path.string`
     public var description: String {
         return string
     }
 }
 
 extension Path: CustomDebugStringConvertible {
+    /// Returns eg. `Path(string: "/foo")`
     public var debugDescription: String {
         return "Path(string: \(string))"
     }

Sources/Path+ls.swift

@@ -1,24 +1,64 @@
 import Foundation
 
-public extension Path {
-    /// same as the `ls` command ∴ is ”shallow”
-    func ls() throws -> [Entry] {
-        let relativePaths = try FileManager.default.contentsOfDirectory(atPath: string)
-        func convert(relativePath: String) -> Entry {
-            let path = self/relativePath
+/**
+ A file entry from a directory listing.
+ - SeeAlso: `ls()`
+*/
+public struct Entry {
+    /// The kind of this directory entry.
+    public enum Kind {
+        /// The path is a file.
+        case file
+        /// The path is a directory.
+        case directory
+    }
+    /// The kind of this entry.
+    public let kind: Kind
+    /// The path of this entry.
+    public let path: Path
+}
+
+public extension Path {    
+    //MARK: Directory Listings
+
+    /**
+     Same as the `ls -a` command ∴ output is ”shallow” and unsorted.
+     - Parameter includeHiddenFiles: If `true`, hidden files are included in the results. Defaults to `true`.
+     - Important: `includeHiddenFiles` does not work on Linux
+     */
+    func ls(includeHiddenFiles: Bool = true) throws -> [Entry] {
+        var opts = FileManager.DirectoryEnumerationOptions()
+    #if !os(Linux)
+        if !includeHiddenFiles {
+            opts.insert(.skipsHiddenFiles)
+        }
+    #endif
+        let paths = try FileManager.default.contentsOfDirectory(at: url, includingPropertiesForKeys: nil, options: opts)
+        func convert(url: URL) -> Entry? {
+            guard let path = Path(url.path) else { return nil }
             return Entry(kind: path.isDirectory ? .directory : .file, path: path)
         }
-        return relativePaths.map(convert)
+        return paths.compactMap(convert)
     }
 }
 
-public extension Array where Element == Path.Entry {
+/// Convenience functions for the array return value of `Path.ls()`
+public extension Array where Element == Entry {
+    /// Filters the list of entries to be a list of Paths that are directories.
     var directories: [Path] {
         return compactMap {
             $0.kind == .directory ? $0.path : nil
         }
     }
 
+    /// Filters the list of entries to be a list of Paths that are files.
+    var files: [Path] {
+        return compactMap {
+            $0.kind == .file ? $0.path : nil
+        }
+    }
+
+    /// Filters the list of entries to be a list of Paths that are files with the specified extension.
     func files(withExtension ext: String) -> [Path] {
         return compactMap {
             $0.kind == .file && $0.path.extension == ext ? $0.path : nil

Sources/Path->Bool.swift

@@ -1,21 +1,42 @@
 import Foundation
 
 public extension Path {
-    var isWritable: Bool {
-        return FileManager.default.isWritableFile(atPath: string)
-    }
-
-    var isDirectory: Bool {
-        var isDir: ObjCBool = false
-        return FileManager.default.fileExists(atPath: string, isDirectory: &isDir) && isDir.boolValue
+    //MARK: Filesystem Properties
+
+    /// Returns true if the path represents an actual filesystem entry.
+    var exists: Bool {
+        return FileManager.default.fileExists(atPath: string)
     }
 
+    /// Returns true if the path represents an actual filesystem entry that is *not* a directory.
     var isFile: Bool {
         var isDir: ObjCBool = true
         return FileManager.default.fileExists(atPath: string, isDirectory: &isDir) && !isDir.boolValue
     }
 
-    var exists: Bool {
-        return FileManager.default.fileExists(atPath: string)
+    /// Returns true if the path represents an actual directory.
+    var isDirectory: Bool {
+        var isDir: ObjCBool = false
+        return FileManager.default.fileExists(atPath: string, isDirectory: &isDir) && isDir.boolValue
+    }
+
+    /// Returns true if the path represents an actual file that is also readable by the current user.
+    var isReadable: Bool {
+        return FileManager.default.isReadableFile(atPath: string)
+    }
+
+    /// Returns true if the path represents an actual file that is also writable by the current user.
+    var isWritable: Bool {
+        return FileManager.default.isWritableFile(atPath: string)
+    }
+        
+    /// Returns true if the path represents an actual file that is also deletable by the current user.
+    var isDeletable: Bool {
+        return FileManager.default.isDeletableFile(atPath: string)
+    }
+
+    /// Returns true if the path represents an actual file that is also executable by the current user.
+    var isExecutable: Bool {
+        return FileManager.default.isExecutableFile(atPath: string)
     }
 }

Sources/Path.swift

@@ -1,50 +1,134 @@
 import Foundation
 
+/**
+ A `Path` represents an absolute path on a filesystem.
+
+ All functions on `Path` are chainable and short to facilitate doing sequences
+ of file operations in a concise manner.
+
+ `Path` supports `Codable`, and can be configured to
+ [encode paths *relatively*](https://github.com/mxcl/Path.swift/#codable).
+
+ Sorting a `Sequence` of `Path`s will return the locale-aware sort order, which
+ will give you the same order as Finder.
+
+ Converting from a `String` is a common first step, here are the recommended
+ ways to do that:
+
+     let p1 = Path.root/pathString
+     let p2 = Path.root/url.path
+     let p3 = Path.cwd/relativePathString
+     let p4 = Path(userInput) ?? Path.cwd/userInput
+
+ If you are constructing Paths from static-strings we provide support for
+ dynamic members:
+
+     let p1 = Path.root.usr.bin.ls  // => /usr/bin/ls
+
+ - Note: There may not be an actual filesystem entry at the path. The underlying
+   representation for `Path` is `String`.
+ */
+
+@dynamicMemberLookup
 public struct Path: Equatable, Hashable, Comparable {
+
+    init(string: String) {
+        self.string = string
+    }
+
+    /// Returns `nil` unless fed an absolute path.
+    public init?(_ description: String) {
+        guard description.starts(with: "/") || description.starts(with: "~/") else { return nil }
+        self.init(string: (description as NSString).standardizingPath)
+    }
+
+    /// :nodoc:
+    public subscript(dynamicMember pathComponent: String) -> Path {
+        let str = (string as NSString).appendingPathComponent(pathComponent)
+        return Path(string: str)
+    }
+
+//MARK: Properties
+
+    /// The underlying filesystem path
     public let string: String
 
-    public static var cwd: Path {
-        return Path(string: FileManager.default.currentDirectoryPath)
-    }
-
-    public static var root: Path {
-        return Path(string: "/")
-    }
-
-    public static var home: Path {
-        return Path(string: NSHomeDirectory())
-    }
-
-    @inlinable
-    public var `extension`: String {
-        return (string as NSString).pathExtension
-    }
-
-    /// - Note: always returns a valid path, `Path.root.parent` *is* `Path.root`
-    public var parent: Path {
-        return Path(string: (string as NSString).deletingLastPathComponent)
-    }
-
-    @inlinable
+    /// Returns a `URL` representing this file path.
     public var url: URL {
         return URL(fileURLWithPath: string)
     }
 
-    public func basename(dropExtension: Bool = false) -> String {
-        let str = string as NSString
-        if !dropExtension {
-            return str.lastPathComponent
+    /**
+     Returns the parent directory for this path.
+
+     Path is not aware of the nature of the underlying file, but this is
+     irrlevant since the operation is the same irrespective of this fact.
+
+     - Note: always returns a valid path, `Path.root.parent` *is* `Path.root`.
+     */
+    public var parent: Path {
+        return Path(string: (string as NSString).deletingLastPathComponent)
+    }
+
+    /**
+     Returns the filename extension of this path.
+     - Remark: Implemented via `NSString.pathExtension`.
+     - Note: We special case eg. `foo.tar.gz`.
+     */
+    @inlinable
+    public var `extension`: String {
+        if string.hasSuffix(".tar.gz") {
+            return "tar.gz"
         } else {
-            let ext = str.pathExtension
-            if !ext.isEmpty {
-                return String(str.lastPathComponent.dropLast(ext.count + 1))
-            } else {
-                return str.lastPathComponent
-            }
+            return (string as NSString).pathExtension
         }
     }
 
-    //TODO another variant that returns `nil` if result would start with `..`
+//MARK: Pathing
+
+    /**
+     Joins a path and a string to produce a new path.
+
+         Path.root.join("a")             // => /a
+         Path.root.join("a/b")           // => /a/b
+         Path.root.join("a").join("b")   // => /a/b
+         Path.root.join("a").join("/b")  // => /a/b
+
+     - Parameter pathComponent: The string to join with this path.
+     - Returns: A new joined path.
+     - SeeAlso: `Path./(_:_:)`
+     */
+    public func join<S>(_ pathComponent: S) -> Path where S: StringProtocol {
+        //TODO standardizingPath does more than we want really (eg tilde expansion)
+        let str = (string as NSString).appendingPathComponent(String(pathComponent))
+        return Path(string: (str as NSString).standardizingPath)
+    }
+
+    /**
+     Joins a path and a string to produce a new path.
+
+         Path.root/"a"       // => /a
+         Path.root/"a/b"     // => /a/b
+         Path.root/"a"/"b"   // => /a/b
+         Path.root/"a"/"/b"  // => /a/b
+
+     - Parameter lhs: The base path to join with `rhs`.
+     - Parameter rhs: The string to join with this `lhs`.
+     - Returns: A new joined path.
+     - SeeAlso: `join(_:)`
+     */
+    @inlinable
+    public static func /<S>(lhs: Path, rhs: S) -> Path where S: StringProtocol {
+        return lhs.join(rhs)
+    }
+
+    /**
+     Returns a string representing the relative path to `base`.
+
+     - Note: If `base` is not a logical prefix for `self` your result will be prefixed some number of `../` components.
+     - Parameter base: The base to which we calculate the relative path.
+     - ToDo: Another variant that returns `nil` if result would start with `..`
+     */
     public func relative(to base: Path) -> String {
         // Split the two paths into their components.
         // FIXME: The is needs to be optimized to avoid unncessary copying.
@@ -75,28 +159,33 @@ public struct Path: Equatable, Hashable, Comparable {
         }
     }
 
-    public func join<S>(_ part: S) -> Path where S: StringProtocol {
-        //TODO standardizingPath does more than we want really (eg tilde expansion)
-        let str = (string as NSString).appendingPathComponent(String(part))
-        return Path(string: (str as NSString).standardizingPath)
+    /**
+     The basename for the provided file, optionally dropping the file extension.
+
+         Path.root.join("foo.swift").basename()  // => "foo.swift"
+         Path.root.join("foo.swift").basename(dropExtension: true)  // => "foo"
+
+     - Returns: A string that is the filename’s basename.
+     - Parameter dropExtension: If `true` returns the basename without its file extension.
+     */
+    public func basename(dropExtension: Bool = false) -> String {
+        let str = string as NSString
+        if !dropExtension {
+            return str.lastPathComponent
+        } else {
+            let ext = str.pathExtension
+            if !ext.isEmpty {
+                return String(str.lastPathComponent.dropLast(ext.count + 1))
+            } else {
+                return str.lastPathComponent
+            }
+        }
     }
 
+    /// Returns the locale-aware sort order for the two paths.
+    /// :nodoc:
     @inlinable
     public static func <(lhs: Path, rhs: Path) -> Bool {
         return lhs.string.compare(rhs.string, locale: .current) == .orderedAscending
     }
-
-    public struct Entry {
-        public enum Kind {
-            case file
-            case directory
-        }
-        public let kind: Kind
-        public let path: Path
-    }
-}
-
-@inlinable
-public func /<S>(lhs: Path, rhs: S) -> Path where S: StringProtocol {
-    return lhs.join(rhs)
 }

Sources/TemporaryDirectory.swift

@@ -1,21 +0,0 @@
-import Foundation
-
-public class TemporaryDirectory {
-    public let url: URL
-    public var path: Path { return Path(string: url.path) }
-
-    public init() throws {
-        url = try FileManager.default.url(for: .itemReplacementDirectory, in: .userDomainMask, appropriateFor: URL(fileURLWithPath: "/"), create: true)
-    }
-
-    deinit {
-        _ = try? FileManager.default.removeItem(at: url)
-    }
-}
-
-public extension Path {
-    static func mktemp<T>(body: (Path) throws -> T) throws -> T {
-        let tmp = try TemporaryDirectory()
-        return try body(tmp.path)
-    }
-}

Tests/PathTests/PathTests.swift

@@ -12,15 +12,44 @@ class PathTests: XCTestCase {
     }
 
     func testEnumeration() throws {
+        let tmpdir_ = try TemporaryDirectory()
+        let tmpdir = tmpdir_.path
+        try tmpdir.a.mkdir().c.touch()
+        try tmpdir.join("b.swift").touch()
+        try tmpdir.c.touch()
+        try tmpdir.join(".d").mkdir().e.touch()
+
+        var paths = Set<String>()
+        let lsrv = try tmpdir.ls()
+        var dirs = 0
+        for entry in lsrv {
+            if entry.kind == .directory {
+                dirs += 1
+            }
+            paths.insert(entry.path.basename())
+        }
+        XCTAssertEqual(dirs, 2)
+        XCTAssertEqual(dirs, lsrv.directories.count)
+        XCTAssertEqual(["a", ".d"], Set(lsrv.directories.map{ $0.relative(to: tmpdir) }))
+        XCTAssertEqual(["b.swift", "c"], Set(lsrv.files.map{ $0.relative(to: tmpdir) }))
+        XCTAssertEqual(["b.swift"], Set(lsrv.files(withExtension: "swift").map{ $0.relative(to: tmpdir) }))
+        XCTAssertEqual(["c"], Set(lsrv.files(withExtension: "").map{ $0.relative(to: tmpdir) }))
+        XCTAssertEqual(paths, ["a", "b.swift", "c", ".d"])
+        
+    }
+
+    func testEnumerationSkippingHiddenFiles() throws {
+    #if !os(Linux)
         let tmpdir_ = try TemporaryDirectory()
         let tmpdir = tmpdir_.path
         try tmpdir.join("a").mkdir().join("c").touch()
         try tmpdir.join("b").touch()
         try tmpdir.join("c").touch()
-
+        try tmpdir.join(".d").mkdir().join("e").touch()
+        
         var paths = Set<String>()
         var dirs = 0
-        for entry in try tmpdir.ls() {
+        for entry in try tmpdir.ls(includeHiddenFiles: false) {
             if entry.kind == .directory {
                 dirs += 1
             }
@@ -28,6 +57,7 @@ class PathTests: XCTestCase {
         }
         XCTAssertEqual(dirs, 1)
         XCTAssertEqual(paths, ["a", "b", "c"])
+    #endif
     }
 
     func testRelativeTo() {
@@ -37,12 +67,24 @@ class PathTests: XCTestCase {
 
     func testExists() {
         XCTAssert(Path.root.exists)
-        XCTAssert((Path.root/"Users").exists)
+        XCTAssert((Path.root/"bin").exists)
     }
 
     func testIsDirectory() {
         XCTAssert(Path.root.isDirectory)
-        XCTAssert((Path.root/"Users").isDirectory)
+        XCTAssert((Path.root/"bin").isDirectory)
+    }
+
+    func testExtension() {
+        XCTAssertEqual(Path.root.join("a.swift").extension, "swift")
+        XCTAssertEqual(Path.root.join("a").extension, "")
+        XCTAssertEqual(Path.root.join("a.").extension, "")
+        XCTAssertEqual(Path.root.join("a..").extension, "")
+        XCTAssertEqual(Path.root.join("a..swift").extension, "swift")
+        XCTAssertEqual(Path.root.join("a..swift.").extension, "")
+        XCTAssertEqual(Path.root.join("a.tar.gz").extension, "tar.gz")
+        XCTAssertEqual(Path.root.join("a..tar.gz").extension, "tar.gz")
+        XCTAssertEqual(Path.root.join("a..tar..gz").extension, "gz")
     }
 
     func testMktemp() throws {
@@ -59,7 +101,7 @@ class PathTests: XCTestCase {
         try Path.mktemp {
             for _ in 0...1 {
                 try $0.join("a").mkdir()
-                try $0.join("b/c").mkpath()
+                try $0.join("b/c").mkdir(.p)
             }
         }
     }
@@ -93,4 +135,43 @@ class PathTests: XCTestCase {
         decoder.userInfo[.relativePath] = root
         XCTAssertEqual(try decoder.decode([Path].self, from: data), input)
     }
+
+    func testJoin() {
+        let prefix = Path.root/"Users/mxcl"
+
+        XCTAssertEqual(prefix/"b", Path("/Users/mxcl/b"))
+        XCTAssertEqual(prefix/"b"/"c", Path("/Users/mxcl/b/c"))
+        XCTAssertEqual(prefix/"b/c", Path("/Users/mxcl/b/c"))
+        XCTAssertEqual(prefix/"/b", Path("/Users/mxcl/b"))
+        let b = "b"
+        let c = "c"
+        XCTAssertEqual(prefix/b/c, Path("/Users/mxcl/b/c"))
+        XCTAssertEqual(Path.root/"~b", Path("/~b"))
+        XCTAssertEqual(Path.root/"~/b", Path("/~/b"))
+        XCTAssertEqual(Path("~/foo"), Path.home/"foo")
+        XCTAssertNil(Path("~foo"))
+
+        XCTAssertEqual(Path.root/"a/foo"/"../bar", Path.root/"a/bar")
+        XCTAssertEqual(Path.root/"a/foo"/"/../bar", Path.root/"a/bar")
+        XCTAssertEqual(Path.root/"a/foo"/"../../bar", Path.root/"bar")
+        XCTAssertEqual(Path.root/"a/foo"/"../../../bar", Path.root/"bar")
+    }
+
+    func testDynamicMember() {
+        XCTAssertEqual(Path.root.Documents, Path.root/"Documents")
+
+        let a = Path.home.foo
+        XCTAssertEqual(a.Documents, Path.home/"foo/Documents")
+    }
+
+    func testCopyInto() throws {
+        try Path.mktemp { root in
+            let bar = try root.join("bar").touch()
+            try Path.mktemp { root in
+                try root.join("bar").touch()
+                XCTAssertThrowsError(try bar.copy(into: root))
+                try bar.copy(into: root, overwrite: true)
+            }
+        }
+    }
 }

Tests/PathTests/TemporaryDirectory.swift

@@ -0,0 +1,71 @@
+@testable import Path
+import Foundation
+
+class TemporaryDirectory {
+    let url: URL
+    var path: Path { return Path(string: url.path) }
+
+    /**
+     Creates a new temporary directory.
+
+     The directory is recursively deleted when this object deallocates.
+
+     If you need a temporary directory on a specific volume use the `appropriateFor`
+     parameter.
+
+     - Important: If you are moving a file, ensure to use the `appropriateFor`
+     parameter, since it is volume aware and moving the file across volumes will take
+     exponentially longer!
+     - Important: The `appropriateFor` parameter does not work on Linux.
+     - Parameter appropriateFor: The temporary directory will be located on this
+     volume.
+    */
+    init(appropriateFor: URL? = nil) throws {
+      #if !os(Linux)
+        let appropriate: URL
+        if let appropriateFor = appropriateFor {
+            appropriate = appropriateFor
+        } else if #available(OSX 10.12, iOS 10, tvOS 10, watchOS 3, *) {
+            appropriate = FileManager.default.temporaryDirectory
+        } else {
+            appropriate = URL(fileURLWithPath: NSTemporaryDirectory())
+        }
+        url = try FileManager.default.url(for: .itemReplacementDirectory, in: .userDomainMask, appropriateFor: appropriate, create: true)
+      #else
+        let envs = ProcessInfo.processInfo.environment
+        let env = envs["TMPDIR"] ?? envs["TEMP"] ?? envs["TMP"] ?? "/tmp"
+        let dir = Path.root/env/"swift-sh.XXXXXX"
+        var template = [UInt8](dir.string.utf8).map({ Int8($0) }) + [Int8(0)]
+        guard mkdtemp(&template) != nil else { throw CocoaError.error(.featureUnsupported) }
+        url = URL(fileURLWithPath: String(cString: template))
+      #endif
+    }
+
+    deinit {
+        _ = try? FileManager.default.removeItem(at: url)
+    }
+}
+
+extension Path {
+    static func mktemp<T>(body: (Path) throws -> T) throws -> T {
+        let tmp = try TemporaryDirectory()
+        return try body(tmp.path)
+    }
+}
+
+
+#if !os(macOS) && !os(Linux)
+import XCTest
+
+// SwiftPM generates code that is improperly escaped thus we require this to
+// compile on iOS & tvOS.
+public typealias XCTestCaseEntry = (testCaseClass: XCTestCase.Type, allTests: [(String, (XCTestCase) throws -> Void)])
+
+public func testCase<T: XCTestCase>(_ allTests: [(String, (T) -> () throws -> Void)]) -> XCTestCaseEntry {
+    fatalError()
+}
+
+public func testCase<T: XCTestCase>(_ allTests: [(String, (T) -> () -> Void)]) -> XCTestCaseEntry {
+    fatalError()
+}
+#endif

Tests/PathTests/XCTestManifests.swift

@@ -5,9 +5,14 @@ extension PathTests {
         ("testBasename", testBasename),
         ("testCodable", testCodable),
         ("testConcatenation", testConcatenation),
+        ("testCopyInto", testCopyInto),
+        ("testDynamicMember", testDynamicMember),
         ("testEnumeration", testEnumeration),
+        ("testEnumerationSkippingHiddenFiles", testEnumerationSkippingHiddenFiles),
         ("testExists", testExists),
+        ("testExtension", testExtension),
         ("testIsDirectory", testIsDirectory),
+        ("testJoin", testJoin),
         ("testMkpathIfExists", testMkpathIfExists),
         ("testMktemp", testMktemp),
         ("testRelativePathCodable", testRelativePathCodable),