Add stash apply & pop support

ObjectiveGit/GTRepository+Stashing.h

@@ -19,6 +19,27 @@ typedef NS_OPTIONS(NSInteger, GTRepositoryStashFlag) {
 	GTRepositoryStashFlagIncludeIgnored = GIT_STASH_INCLUDE_IGNORED
 };
 
+/// Flags for -applyStashAtIndex:flags:error: and
+/// -popStashAtIndex:flags:error.
+/// Those can be ORed together. See git_stash_apply_flags for additional information.
+typedef NS_OPTIONS(NSInteger, GTRepositoryStashApplyFlag) {
+	GTRepositoryStashApplyFlagDefault = GIT_STASH_APPLY_DEFAULT,
+	GTRepositoryStashApplyFlagReinstateIndex = GIT_STASH_APPLY_REINSTATE_INDEX,
+};
+
+/// Enum representing the current state of a stash apply/pop operation.
+/// See git_stash_apply_progress_t for additional information.
+typedef NS_ENUM(NSInteger, GTRepositoryStashApplyProgress) {
+	GTRepositoryStashApplyProgressNone = GIT_STASH_APPLY_PROGRESS_NONE,
+	GTRepositoryStashApplyProgressLoadingStash = GIT_STASH_APPLY_PROGRESS_LOADING_STASH,
+	GTRepositoryStashApplyProgressAnalyzeIndex = GIT_STASH_APPLY_PROGRESS_ANALYZE_INDEX,
+	GTRepositoryStashApplyProgressAnalyzeModified = GIT_STASH_APPLY_PROGRESS_ANALYZE_MODIFIED,
+	GTRepositoryStashApplyProgressAnalyzeUntracked = GIT_STASH_APPLY_PROGRESS_ANALYZE_UNTRACKED,
+	GTRepositoryStashApplyProgressGheckoutUntracked = GIT_STASH_APPLY_PROGRESS_CHECKOUT_UNTRACKED,
+	GTRepositoryStashApplyProgressCheckoutModified = GIT_STASH_APPLY_PROGRESS_CHECKOUT_MODIFIED,
+	GTRepositoryStashApplyProgressDone = GIT_STASH_APPLY_PROGRESS_DONE,
+};
+
 NS_ASSUME_NONNULL_BEGIN
 
 @interface GTRepository (Stashing)
@@ -41,6 +62,24 @@ NS_ASSUME_NONNULL_BEGIN
 ///         will cause enumeration to stop after the block returns. Must not be nil.
 - (void)enumerateStashesUsingBlock:(void (^)(NSUInteger index, NSString * __nullable message, GTOID * __nullable oid, BOOL *stop))block;
 
+/// Apply stashed changes.
+///
+/// index - The index of the stash to apply. 0 is the latest one.
+/// flags - The flags to use when applying the stash.
+/// error - If not NULL, set to any error that occurred.
+///
+/// Returns YES if the requested stash was successfully applied, NO otherwise.
+- (BOOL)applyStashAtIndex:(NSUInteger)index flags:(GTRepositoryStashApplyFlag)flags error:(NSError **)error progressBlock:(nullable void (^)(GTRepositoryStashApplyProgress progress, BOOL *stop))progressBlock;
+
+/// Pop stashed changes.
+///
+/// index - The index of the stash to apply. 0 is the most recent stash.
+/// flags - The flags to use when applying the stash.
+/// error - If not NULL, set to any error that occurred.
+///
+/// Returns YES if the requested stash was successfully applied, NO otherwise.
+- (BOOL)popStashAtIndex:(NSUInteger)index flags:(GTRepositoryStashApplyFlag)flags error:(NSError **)error progressBlock:(nullable void (^)(GTRepositoryStashApplyProgress progress, BOOL *stop))progressBlock;
+
 /// Drop a stash from the repository's list of stashes.
 ///
 /// index - The index of the stash to drop, where 0 is the most recent stash.

ObjectiveGit/GTRepository+Stashing.m

@@ -50,10 +50,53 @@ - (void)enumerateStashesUsingBlock:(GTRepositoryStashEnumerationBlock)block {
 	git_stash_foreach(self.git_repository, &stashEnumerationCallback, (__bridge void *)block);
 }
 
+static int stashApplyProgressCallback(git_stash_apply_progress_t progress, void *payload) {
+	void (^block)(GTRepositoryStashApplyProgress, BOOL *) = (__bridge id)payload;
+
+	BOOL stop = NO;
+	block((GTRepositoryStashApplyProgress)progress, &stop);
+
+	return (stop ? GIT_EUSER : 0);
+}
+
+- (BOOL)applyStashAtIndex:(NSUInteger)index flags:(GTRepositoryStashApplyFlag)flags error:(NSError **)error progressBlock:(nullable void (^)(GTRepositoryStashApplyProgress progress, BOOL *stop))progressBlock {
+	git_stash_apply_options stash_options = GIT_STASH_APPLY_OPTIONS_INIT;
+
+	stash_options.flags = (git_stash_apply_flags)flags;
+	if (progressBlock != nil) {
+		stash_options.progress_cb = stashApplyProgressCallback;
+		stash_options.progress_payload = (__bridge void *)progressBlock;
+	}
+
+	int gitError = git_stash_apply(self.git_repository, index, &stash_options);
+	if (gitError != GIT_OK) {
+		if (error != NULL) *error = [NSError git_errorFor:gitError description:@"Stash apply failed" failureReason:@"The stash at index %ld couldn't be applied.", (unsigned long)index];
+		return NO;
+	}
+	return YES;
+}
+
+- (BOOL)popStashAtIndex:(NSUInteger)index flags:(GTRepositoryStashApplyFlag)flags error:(NSError **)error progressBlock:(nullable void (^)(GTRepositoryStashApplyProgress progress, BOOL *stop))progressBlock {
+	git_stash_apply_options stash_options = GIT_STASH_APPLY_OPTIONS_INIT;
+
+	stash_options.flags = (git_stash_apply_flags)flags;
+	if (progressBlock != nil) {
+		stash_options.progress_cb = stashApplyProgressCallback;
+		stash_options.progress_payload = (__bridge void *)progressBlock;
+	}
+
+	int gitError = git_stash_pop(self.git_repository, index, &stash_options);
+	if (gitError != GIT_OK) {
+		if (error != NULL) *error = [NSError git_errorFor:gitError description:@"Stash pop failed" failureReason:@"The stash at index %ld couldn't be applied.", (unsigned long)index];
+		return NO;
+	}
+	return YES;
+}
+
 - (BOOL)dropStashAtIndex:(NSUInteger)index error:(NSError **)error {
 	int gitError = git_stash_drop(self.git_repository, index);
 	if (gitError != GIT_OK) {
-		if (error != NULL) *error = [NSError git_errorFor:gitError description:@"Failed to drop stash."];
+		if (error != NULL) *error = [NSError git_errorFor:gitError description:@"Stash drop failed" failureReason:@"The stash at index %ld couldn't be dropped", (unsigned long)index];
 		return NO;
 	}
 

ObjectiveGitTests/GTRepositoryStashingSpec.m

@@ -120,6 +120,80 @@
 	expect(@(lastIndex)).to(equal(@2));
 });
 
+it(@"should apply stashes", ^{
+	expect(@([@"foobar" writeToURL:[repository.fileURL URLByAppendingPathComponent:@"new-test-file"] atomically:YES encoding:NSUTF8StringEncoding error:NULL])).to(beTruthy());
+
+	NSError *error = nil;
+	GTCommit *stash = [repository stashChangesWithMessage:nil flags:GTRepositoryStashFlagIncludeUntracked error:&error];
+	expect(stash).notTo(beNil());
+	expect(error).to(beNil());
+
+	__block BOOL progressCalled = NO;
+	BOOL success = [repository applyStashAtIndex:0 flags:GTRepositoryStashApplyFlagDefault error:&error progressBlock:^void(GTRepositoryStashApplyProgress step, BOOL *stop) {
+		progressCalled = YES;
+	}];
+	expect(@(success)).to(beTruthy());
+	expect(@(progressCalled)).to(beTruthy());
+	expect(error).to(beNil());
+
+	expect([NSString stringWithContentsOfURL:[repository.fileURL URLByAppendingPathComponent:@"new-test-file"] encoding:NSUTF8StringEncoding error:NULL]).to(equal(@"foobar"));
+});
+
+
+it(@"should drop stashes", ^{
+	expect(@([@"foobar" writeToURL:[repository.fileURL URLByAppendingPathComponent:@"new-test-file"] atomically:YES encoding:NSUTF8StringEncoding error:NULL])).to(beTruthy());
+
+	NSError *error = nil;
+	GTCommit *stash = [repository stashChangesWithMessage:nil flags:GTRepositoryStashFlagIncludeUntracked error:&error];
+	expect(stash).notTo(beNil());
+	expect(error).to(beNil());
+
+	BOOL success = [repository dropStashAtIndex:0 error:&error];
+	expect(@(success)).to(beTruthy());
+	expect(error).to(beNil());
+});
+
+it(@"should fail to apply/drop unknown stashes", ^{
+	NSError *error = nil;
+	BOOL success = NO;
+
+	__block NSUInteger lastStashIndex = 0;
+	[repository enumerateStashesUsingBlock:^(NSUInteger index, NSString * __nullable message, GTOID * __nullable oid, BOOL * __nonnull stop) {
+		lastStashIndex = index;
+	}];
+
+	success = [repository applyStashAtIndex:(lastStashIndex + 1) flags:GTRepositoryStashApplyFlagDefault error:&error progressBlock:nil];
+	expect(@(success)).to(beFalsy());
+	expect(error).notTo(beNil());
+	expect(error.domain).to(equal(GTGitErrorDomain));
+	expect(@(error.code)).to(equal(@(GIT_ENOTFOUND)));
+
+	success = [repository dropStashAtIndex:(lastStashIndex + 1) error:&error];
+	expect(@(success)).to(beFalsy());
+	expect(error).notTo(beNil());
+	expect(error.domain).to(equal(GTGitErrorDomain));
+	expect(@(error.code)).to(equal(@(GIT_ENOTFOUND)));
+});
+
+it(@"should fail to apply conflicting stashes", ^{
+	expect(@([@"foobar" writeToURL:[repository.fileURL URLByAppendingPathComponent:@"new-test-file"] atomically:YES encoding:NSUTF8StringEncoding error:NULL])).to(beTruthy());
+
+	NSError *error = nil;
+	GTCommit *stash = [repository stashChangesWithMessage:nil flags:GTRepositoryStashFlagIncludeUntracked error:&error];
+	expect(stash).notTo(beNil());
+	expect(error).to(beNil());
+
+
+	expect(@([@"barfoo" writeToURL:[repository.fileURL URLByAppendingPathComponent:@"new-test-file"] atomically:YES encoding:NSUTF8StringEncoding error:NULL])).to(beTruthy());
+
+	BOOL success = [repository applyStashAtIndex:0 flags:GTRepositoryStashApplyFlagDefault error:&error progressBlock:nil];
+	expect(@(success)).to(beFalsy());
+	expect(error).notTo(beNil());
+
+	expect(error.domain).to(equal(GTGitErrorDomain));
+	expect(@(error.code)).to(equal(@(GIT_ECONFLICT)));
+});
+
 afterEach(^{
 	[self tearDown];
 });