Merge branch 'jh/notes-merge-in-git-dir-worktree' into maint

Running "notes merge --commit" failed to perform correctly when run
from any directory inside $GIT_DIR/.  When "notes merge" stops with
conflicts, $GIT_DIR/NOTES_MERGE_WORKTREE is the place a user edits
to resolve it.

By Johan Herland (3) and Junio C Hamano (1)
* jh/notes-merge-in-git-dir-worktree:
  notes-merge: Don't remove .git/NOTES_MERGE_WORKTREE; it may be the user's cwd
  notes-merge: use opendir/readdir instead of using read_directory()
  t3310: illustrate failure to "notes merge --commit" inside $GIT_DIR/
  remove_dir_recursively(): Add flag for skipping removal of toplevel dir

dir.c

@@ -1178,6 +1178,7 @@ int remove_dir_recursively(struct strbuf *path, int flag)
 	struct dirent *e;
 	int ret = 0, original_len = path->len, len;
 	int only_empty = (flag & REMOVE_DIR_EMPTY_ONLY);
+	int keep_toplevel = (flag & REMOVE_DIR_KEEP_TOPLEVEL);
 	unsigned char submodule_head[20];
 
 	if ((flag & REMOVE_DIR_KEEP_NESTED_GIT) &&
@@ -1185,9 +1186,14 @@ int remove_dir_recursively(struct strbuf *path, int flag)
 		/* Do not descend and nuke a nested git work tree. */
 		return 0;
 
+	flag &= ~(REMOVE_DIR_KEEP_TOPLEVEL|REMOVE_DIR_KEEP_NESTED_GIT);
 	dir = opendir(path->buf);
-	if (!dir)
-		return rmdir(path->buf);
+	if (!dir) {
+		if (!keep_toplevel)
+			return rmdir(path->buf);
+		else
+			return -1;
+	}
 	if (path->buf[original_len - 1] != '/')
 		strbuf_addch(path, '/');
 
@@ -1202,7 +1208,7 @@ int remove_dir_recursively(struct strbuf *path, int flag)
 		if (lstat(path->buf, &st))
 			; /* fall thru */
 		else if (S_ISDIR(st.st_mode)) {
-			if (!remove_dir_recursively(path, only_empty))
+			if (!remove_dir_recursively(path, flag))
 				continue; /* happy */
 		} else if (!only_empty && !unlink(path->buf))
 			continue; /* happy, too */
@@ -1214,7 +1220,7 @@ int remove_dir_recursively(struct strbuf *path, int flag)
 	closedir(dir);
 
 	strbuf_setlen(path, original_len);
-	if (!ret)
+	if (!ret && !keep_toplevel)
 		ret = rmdir(path->buf);
 	return ret;
 }

dir.h

@@ -102,6 +102,7 @@ extern void setup_standard_excludes(struct dir_struct *dir);
 
 #define REMOVE_DIR_EMPTY_ONLY 01
 #define REMOVE_DIR_KEEP_NESTED_GIT 02
+#define REMOVE_DIR_KEEP_TOPLEVEL 04
 extern int remove_dir_recursively(struct strbuf *path, int flag);
 
 /* tries to remove the path with empty directories along it, ignores ENOENT */

notes-merge.c

@@ -267,7 +267,8 @@ static void check_notes_merge_worktree(struct notes_merge_options *o)
 		 * Must establish NOTES_MERGE_WORKTREE.
 		 * Abort if NOTES_MERGE_WORKTREE already exists
 		 */
-		if (file_exists(git_path(NOTES_MERGE_WORKTREE))) {
+		if (file_exists(git_path(NOTES_MERGE_WORKTREE)) &&
+		    !is_empty_dir(git_path(NOTES_MERGE_WORKTREE))) {
 			if (advice_resolve_conflict)
 				die("You have not concluded your previous "
 				    "notes merge (%s exists).\nPlease, use "
@@ -687,51 +688,60 @@ int notes_merge_commit(struct notes_merge_options *o,
 {
 	/*
 	 * Iterate through files in .git/NOTES_MERGE_WORKTREE and add all
-	 * found notes to 'partial_tree'. Write the updates notes tree to
+	 * found notes to 'partial_tree'. Write the updated notes tree to
 	 * the DB, and commit the resulting tree object while reusing the
 	 * commit message and parents from 'partial_commit'.
 	 * Finally store the new commit object SHA1 into 'result_sha1'.
 	 */
-	struct dir_struct dir;
-	char *path = xstrdup(git_path(NOTES_MERGE_WORKTREE "/"));
-	int path_len = strlen(path), i;
+	DIR *dir;
+	struct dirent *e;
+	struct strbuf path = STRBUF_INIT;
 	char *msg = strstr(partial_commit->buffer, "\n\n");
 	struct strbuf sb_msg = STRBUF_INIT;
+	int baselen;
 
+	strbuf_addstr(&path, git_path(NOTES_MERGE_WORKTREE));
 	if (o->verbosity >= 3)
-		printf("Committing notes in notes merge worktree at %.*s\n",
-			path_len - 1, path);
+		printf("Committing notes in notes merge worktree at %s\n",
+			path.buf);
 
 	if (!msg || msg[2] == '\0')
 		die("partial notes commit has empty message");
 	msg += 2;
 
-	memset(&dir, 0, sizeof(dir));
-	read_directory(&dir, path, path_len, NULL);
-	for (i = 0; i < dir.nr; i++) {
-		struct dir_entry *ent = dir.entries[i];
+	dir = opendir(path.buf);
+	if (!dir)
+		die_errno("could not open %s", path.buf);
+
+	strbuf_addch(&path, '/');
+	baselen = path.len;
+	while ((e = readdir(dir)) != NULL) {
 		struct stat st;
-		const char *relpath = ent->name + path_len;
 		unsigned char obj_sha1[20], blob_sha1[20];
 
-		if (ent->len - path_len != 40 || get_sha1_hex(relpath, obj_sha1)) {
+		if (is_dot_or_dotdot(e->d_name))
+			continue;
+
+		if (strlen(e->d_name) != 40 || get_sha1_hex(e->d_name, obj_sha1)) {
 			if (o->verbosity >= 3)
-				printf("Skipping non-SHA1 entry '%s'\n",
-								ent->name);
+				printf("Skipping non-SHA1 entry '%s%s'\n",
+					path.buf, e->d_name);
 			continue;
 		}
 
+		strbuf_addstr(&path, e->d_name);
 		/* write file as blob, and add to partial_tree */
-		if (stat(ent->name, &st))
-			die_errno("Failed to stat '%s'", ent->name);
-		if (index_path(blob_sha1, ent->name, &st, HASH_WRITE_OBJECT))
-			die("Failed to write blob object from '%s'", ent->name);
+		if (stat(path.buf, &st))
+			die_errno("Failed to stat '%s'", path.buf);
+		if (index_path(blob_sha1, path.buf, &st, HASH_WRITE_OBJECT))
+			die("Failed to write blob object from '%s'", path.buf);
 		if (add_note(partial_tree, obj_sha1, blob_sha1, NULL))
 			die("Failed to add resolved note '%s' to notes tree",
-			    ent->name);
+			    path.buf);
 		if (o->verbosity >= 4)
 			printf("Added resolved note for object %s: %s\n",
 				sha1_to_hex(obj_sha1), sha1_to_hex(blob_sha1));
+		strbuf_setlen(&path, baselen);
 	}
 
 	strbuf_attach(&sb_msg, msg, strlen(msg), strlen(msg) + 1);
@@ -740,20 +750,25 @@ int notes_merge_commit(struct notes_merge_options *o,
 	if (o->verbosity >= 4)
 		printf("Finalized notes merge commit: %s\n",
 			sha1_to_hex(result_sha1));
-	free(path);
+	strbuf_release(&path);
+	closedir(dir);
 	return 0;
 }
 
 int notes_merge_abort(struct notes_merge_options *o)
 {
-	/* Remove .git/NOTES_MERGE_WORKTREE directory and all files within */
+	/*
+	 * Remove all files within .git/NOTES_MERGE_WORKTREE. We do not remove
+	 * the .git/NOTES_MERGE_WORKTREE directory itself, since it might be
+	 * the current working directory of the user.
+	 */
 	struct strbuf buf = STRBUF_INIT;
 	int ret;
 
 	strbuf_addstr(&buf, git_path(NOTES_MERGE_WORKTREE));
 	if (o->verbosity >= 3)
-		printf("Removing notes merge worktree at %s\n", buf.buf);
-	ret = remove_dir_recursively(&buf, 0);
+		printf("Removing notes merge worktree at %s/*\n", buf.buf);
+	ret = remove_dir_recursively(&buf, REMOVE_DIR_KEEP_TOPLEVEL);
 	strbuf_release(&buf);
 	return ret;
 }

t/t3310-notes-merge-manual-resolve.sh

@@ -324,7 +324,7 @@ y and z notes on 4th commit
 EOF
 	git notes merge --commit &&
 	# No .git/NOTES_MERGE_* files left
-	test_must_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
+	test_might_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
 	test_cmp /dev/null output &&
 	# Merge commit has pre-merge y and pre-merge z as parents
 	test "$(git rev-parse refs/notes/m^1)" = "$(cat pre_merge_y)" &&
@@ -386,7 +386,7 @@ test_expect_success 'redo merge of z into m (== y) with default ("manual") resol
 test_expect_success 'abort notes merge' '
 	git notes merge --abort &&
 	# No .git/NOTES_MERGE_* files left
-	test_must_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
+	test_might_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
 	test_cmp /dev/null output &&
 	# m has not moved (still == y)
 	test "$(git rev-parse refs/notes/m)" = "$(cat pre_merge_y)" &&
@@ -453,7 +453,7 @@ EOF
 	# Finalize merge
 	git notes merge --commit &&
 	# No .git/NOTES_MERGE_* files left
-	test_must_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
+	test_might_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
 	test_cmp /dev/null output &&
 	# Merge commit has pre-merge y and pre-merge z as parents
 	test "$(git rev-parse refs/notes/m^1)" = "$(cat pre_merge_y)" &&
@@ -542,7 +542,7 @@ EOF
 test_expect_success 'resolve situation by aborting the notes merge' '
 	git notes merge --abort &&
 	# No .git/NOTES_MERGE_* files left
-	test_must_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
+	test_might_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
 	test_cmp /dev/null output &&
 	# m has not moved (still == w)
 	test "$(git rev-parse refs/notes/m)" = "$(git rev-parse refs/notes/w)" &&
@@ -553,4 +553,23 @@ test_expect_success 'resolve situation by aborting the notes merge' '
 	verify_notes z
 '
 
+cat >expect_notes <<EOF
+foo
+bar
+EOF
+
+test_expect_success 'switch cwd before committing notes merge' '
+	git notes add -m foo HEAD &&
+	git notes --ref=other add -m bar HEAD &&
+	test_must_fail git notes merge refs/notes/other &&
+	(
+		cd .git/NOTES_MERGE_WORKTREE &&
+		echo "foo" > $(git rev-parse HEAD) &&
+		echo "bar" >> $(git rev-parse HEAD) &&
+		git notes merge --commit
+	) &&
+	git notes show HEAD > actual_notes &&
+	test_cmp expect_notes actual_notes
+'
+
 test_done