Merge branch 'gg/worktree-from-the-above' into maint

In a non-bare repository, the behavior of Git when the
core.worktree configuration variable points at a directory that has
a repository as its subdirectory, regressed in Git 2.27 days.
source: <20220616234433.225-1-gg.oss@outlook.com>
source: <20220616231956.154-1-gg.oss@outlook.com>

* gg/worktree-from-the-above:
  dir: minor refactoring / clean-up
  dir: traverse into repository

1 files changed, 28 insertions, 7 deletions

diff --git a/dir.c b/dir.c
index 6ca2ef5..d7cfb08 100644
--- a/dir.c
+++ b/dir.c
@@ -1861,7 +1861,7 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 	 */
 	enum path_treatment state;
 	int matches_how = 0;
-	int nested_repo = 0, check_only, stop_early;
+	int check_only, stop_early;
 	int old_ignored_nr, old_untracked_nr;
 	/* The "len-1" is to strip the final '/' */
 	enum exist_status status = directory_exists_in_index(istate, dirname, len-1);
@@ -1893,16 +1893,37 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 
 	if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
 		!(dir->flags & DIR_NO_GITLINKS)) {
+		/*
+		 * Determine if `dirname` is a nested repo by confirming that:
+		 * 1) we are in a nonbare repository, and
+		 * 2) `dirname` is not an immediate parent of `the_repository->gitdir`,
+		 *    which could occur if the git_dir or worktree location was
+		 *    manually configured by the user; see t2205 testcases 1-3 for
+		 *    examples where this matters
+		 */
+		int nested_repo;
 		struct strbuf sb = STRBUF_INIT;
 		strbuf_addstr(&sb, dirname);
 		nested_repo = is_nonbare_repository_dir(&sb);
+
+		if (nested_repo) {
+			char *real_dirname, *real_gitdir;
+			strbuf_addstr(&sb, ".git");
+			real_dirname = real_pathdup(sb.buf, 1);
+			real_gitdir = real_pathdup(the_repository->gitdir, 1);
+
+			nested_repo = !!strcmp(real_dirname, real_gitdir);
+			free(real_gitdir);
+			free(real_dirname);
+		}
 		strbuf_release(&sb);
-	}
-	if (nested_repo) {
-		if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
-		    (matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC))
-			return path_none;
-		return excluded ? path_excluded : path_untracked;
+
+		if (nested_repo) {
+			if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
+				(matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC))
+				return path_none;
+			return excluded ? path_excluded : path_untracked;
+		}
 	}
 
 	if (!(dir->flags & DIR_SHOW_OTHER_DIRECTORIES)) {