Merge pull request #608 from slavikus/add-checkout-tree

Add -[GTRepository checkoutTree:…] method

Author: pietbrauer

ObjectiveGit/GTRepository.h

@@ -535,6 +535,16 @@ typedef NS_ENUM(NSInteger, GTRepositoryStateType) {
 /// Returns YES if operation was successful, NO otherwise
 - (BOOL)checkoutIndex:(GTIndex *)index options:(nullable GTCheckoutOptions *)options error:(NSError **)error;
 
+/// Checkout a tree
+///
+/// targetTree    - The tree to checkout.
+/// options       - The checkout options to use. Can be nil.
+/// error         - The error if one occurred. Can be NULL.
+///
+/// Returns YES if operation was successful, NO otherwise
+/// Note: this operation will NOT update HEAD to newly checked out tree.
+- (BOOL)checkoutTree:(GTTree *)targetTree options:(nullable GTCheckoutOptions *)options error:(NSError **)error;
+
 /// Flush the gitattributes cache.
 - (void)flushAttributesCache;
 

ObjectiveGit/GTRepository.m

@@ -830,6 +830,10 @@ - (BOOL)checkoutReference:(GTReference *)targetReference options:(GTCheckoutOpti
 	return [self moveHEADToReference:targetReference error:error];
 }
 
+- (BOOL)checkoutTree:(GTTree *)targetTree options:(nullable GTCheckoutOptions *)options error:(NSError **)error {
+	return [self performCheckout:targetTree options:options error:error];
+}
+
 - (BOOL)checkoutIndex:(GTIndex *)index options:(GTCheckoutOptions *)options error:(NSError **)error {
 	int gitError = git_checkout_index(self.git_repository, index.git_index, options.git_checkoutOptions);
 	if (gitError < GIT_OK) {