CheckoutOptions: Support progress callbacks

Gift/Gift.h

@@ -5,3 +5,5 @@ FOUNDATION_EXPORT double GiftVersionNumber;
 
 //! Project version string for Gift.
 FOUNDATION_EXPORT const unsigned char GiftVersionString[];
+
+#import <Gift/GIFTCheckoutOptions.h>

Gift/Repository/Options/Checkout/CheckoutOptions+C.swift

@@ -0,0 +1,9 @@
+internal extension CheckoutOptions {
+  /**
+    Returns a C struct initialized with this options instance's values.
+    Used by libgit2 functions.
+  */
+  internal var cOptions: git_checkout_options {
+    return gift_checkoutOptions(UInt32(strategy.rawValue), progressCallback)
+  }
+}

Gift/Repository/Options/CheckoutOptions.swift → Gift/Repository/Options/Checkout/CheckoutOptions.swift

@@ -7,8 +7,13 @@
 */
 public struct CheckoutOptions {
   internal let strategy: CheckoutStrategy
+  internal let progressCallback: GIFTCheckoutProgressCallback!
 
-  public init(strategy: CheckoutStrategy) {
+  public init(
+    strategy: CheckoutStrategy,
+    progressCallback: GIFTCheckoutProgressCallback! = nil
+  ) {
     self.strategy = strategy
+    self.progressCallback = progressCallback
   }
 }

Gift/Repository/Options/Checkout/GIFTCheckoutOptions.h

@@ -0,0 +1,38 @@
+#import <Foundation/Foundation.h>
+
+typedef struct git_checkout_options git_checkout_options;
+
+/**
+ A callback function that is executed during a checkout.
+
+ @param checkedOutFilePath A path to the file that is being checked out.
+ @param fileIndex The index of the file whose checkout triggered this
+                  callback. For example, when the first file has been
+                  checked out, this is '0'. The second file is '1', the
+                  third is '2', and so on.
+ @param fileCount The total number of files to be checked out. When the
+                  file index is equal to this file count, it can be
+                  inferred that this callback will no longer be called
+                  for the current checkout.
+ */
+typedef void (^GIFTCheckoutProgressCallback)(NSString *checkedOutFilePath,
+                                             NSUInteger fileIndex,
+                                             NSUInteger fileCount);
+
+/**
+ Returns a set of checkout options with the given paramters.
+
+ @warning This function is necessary in order to allow a Swift closure
+          to be used as a progress callback. It is impossible to
+          obtain a reference to a C function from Swift that we may
+          then use to configure a git_checkout_options struct.
+
+ @param strategyValue The raw value of a CheckoutStrategy options set
+                      used to control how a checkout should be performed.
+ @param progressCallback An optional progress callback block to be invoked
+                         as remote files are checked out. Note that this
+                         callback will not be invoked for local checkouts.
+ @return A set of checkout options initialized with the given values.
+ */
+extern git_checkout_options gift_checkoutOptions(unsigned int strategyValue,
+                                                 GIFTCheckoutProgressCallback progressCallback);

Gift/Repository/Options/Checkout/GIFTCheckoutOptions.m

@@ -0,0 +1,34 @@
+#import "GIFTCheckoutOptions.h"
+#import <git2/checkout.h>
+
+#pragma mark - Internal Functions
+
+static void gift_checkoutProgressCallback(const char *cPath,
+                                          size_t completedSteps,
+                                          size_t totalSteps,
+                                          void *payload) {
+  if (payload == NULL) {
+    return;
+  }
+
+  NSString *path = nil;
+  if (cPath != NULL) {
+    path = @(cPath);
+  }
+
+  GIFTCheckoutProgressCallback block = (__bridge GIFTCheckoutProgressCallback)payload;
+  block(path, completedSteps, totalSteps);
+}
+
+#pragma mark - Public Interface
+
+extern git_checkout_options gift_checkoutOptions(unsigned int strategyValue,
+                                                 GIFTCheckoutProgressCallback progressCallback) {
+  git_checkout_options options = GIT_CHECKOUT_OPTIONS_INIT;
+  options.checkout_strategy = strategyValue;
+  if (progressCallback != nil) {
+    options.progress_cb = gift_checkoutProgressCallback;
+    options.progress_payload = (__bridge void *)[progressCallback copy];
+  }
+  return options;
+}

GiftTests/Repository/RepositorySpec.swift

@@ -17,17 +17,18 @@ class RepositorySpec: QuickSpec {
     }
 
     describe("cloneRepository") {
+      var remoteURL: NSURL!
+      var destinationURL: NSURL!
+
       context("on the local filesystem") {
-        var remoteURL: NSURL!
-        var destinationURL: NSURL!
         beforeEach {
           remoteURL = temporaryDirectoryURL().URLByAppendingPathComponent("park-slope")
           destinationURL = temporaryDirectoryURL().URLByAppendingPathComponent("sunset-park")
         }
 
         context("but the remote does not exist") {
           it("fails") {
-            let repository = cloneRepository(remoteURL, destinationURL)
+            let repository = cloneRepository(remoteURL,destinationURL)
             let path = remoteURL.path!.stringByResolvingSymlinksInPath
             let faiureMessage = "Failed to resolve path '\(path)': No such file or directory"
             expect(repository).to(haveFailed(localizedDescription: faiureMessage))
@@ -44,6 +45,32 @@ class RepositorySpec: QuickSpec {
           }
         }
       }
+
+      xcontext("from a remote URL") {
+        beforeEach {
+          remoteURL = NSURL(string: "git://git.libssh2.org/libssh2.git")
+          destinationURL = temporaryDirectoryURL().URLByAppendingPathComponent("libssh2")
+        }
+
+        context("and the remote exists") {
+          it("is succesful") {
+            let options = CloneOptions(
+              checkoutOptions: CheckoutOptions(
+                strategy: CheckoutStrategy.SafeCreate,
+                progressCallback: { (path: String!, completedSteps: UInt, totalSteps: UInt) in
+                  println("path '\(path != nil ? path : nil)', "
+                          + "completedSteps '\(completedSteps)', "
+                          + "totalSteps '\(totalSteps)'")
+                }
+              ),
+              remoteCallbacks: RemoteCallbacks()
+            )
+
+            expect(cloneRepository(remoteURL, destinationURL, options: options))
+              .to(haveSucceeded())
+          }
+        }
+      }
     }
   }
 }