Add argument for build root override. (#3864)

This will allow CI to give a directory on a volume that has more storage
space, allowing the build to succeed.

Author: ryanwilson

ZipBuilder/Sources/ZipBuilder/FileManager+Utils.swift

@@ -110,9 +110,12 @@ public extension FileManager {
   /// Returns a deterministic path of a temporary directory for the given name. Note: This does
   /// *not* create the directory if it doesn't exist, merely generates the name for creation.
   func temporaryDirectory(withName name: String) -> URL {
-    // Get access to the temporary directory.
+    // Get access to the temporary directory. This could be passed in via `LaunchArgs`, or use the
+    // default temporary directory.
     let tempDir: URL
-    if #available(OSX 10.12, *) {
+    if let root = LaunchArgs.shared.buildRoot {
+      tempDir = root
+    } else if #available(OSX 10.12, *) {
       tempDir = temporaryDirectory
     } else {
       tempDir = URL(fileURLWithPath: NSTemporaryDirectory())

ZipBuilder/Sources/ZipBuilder/LaunchArgs.swift

@@ -39,6 +39,7 @@ extension FileManager: FileChecker {}
 struct LaunchArgs {
   /// Keys associated with the launch args. See `Usage` for descriptions of each flag.
   private enum Key: String, CaseIterable {
+    case buildRoot
     case carthageDir
     case customSpecRepos
     case existingVersions
@@ -51,6 +52,9 @@ struct LaunchArgs {
     /// Usage description for the key.
     var usage: String {
       switch self {
+      case .buildRoot:
+        return "The root directory for build artifacts. If `nil`, a temporary directory will be " +
+          "used."
       case .carthageDir:
         return "The directory pointing to all Carthage JSON manifests. Passing this flag enables" +
           "the Carthage build."
@@ -79,6 +83,9 @@ struct LaunchArgs {
   /// verify expected version numbers.
   let allSDKsPath: URL?
 
+  /// The root directory for build artifacts. If `nil`, a temporary directory will be used.
+  let buildRoot: URL?
+
   /// The directory pointing to all Carthage JSON manifests. Passing this flag enables the Carthage
   /// build.
   let carthageDir: URL?
@@ -105,6 +112,9 @@ struct LaunchArgs {
   /// A flag to update the Pod Repo or not.
   let updatePodRepo: Bool
 
+  /// The shared instance for processing launch args using default arguments.
+  static let shared: LaunchArgs = LaunchArgs()
+
   /// Initializes with values pulled from the instance of UserDefaults passed in.
   ///
   /// - Parameters:
@@ -219,6 +229,20 @@ struct LaunchArgs {
       carthageDir = nil
     }
 
+    // Parse the Carthage directory key.
+    if let buildRoot = defaults.string(forKey: Key.buildRoot.rawValue) {
+      let url = URL(fileURLWithPath: buildRoot)
+      guard fileChecker.directoryExists(at: url) else {
+        LaunchArgs.exitWithUsageAndLog("Could not parse \(Key.buildRoot) key: value " +
+          "passed in is not a file URL or the directory does not exist. Value: \(buildRoot)")
+      }
+
+      self.buildRoot = url.standardizedFileURL
+    } else {
+      // No argument was passed in.
+      buildRoot = nil
+    }
+
     updatePodRepo = defaults.bool(forKey: Key.updatePodRepo.rawValue)
   }
 

ZipBuilder/Sources/ZipBuilder/main.swift

@@ -25,7 +25,7 @@ do {
 }
 
 // Get the launch arguments, parsed by user defaults.
-let args = LaunchArgs()
+let args = LaunchArgs.shared
 
 // Keep timing for how long it takes to build the zip file for information purposes.
 let buildStart = Date()