[GSoC Patch 3/7] repo: add path.objects with absolute and relative suffix formatting

[K Jayatheerth <jayatheerthkulkarni2005@gmail.com>]

Tools and deployment hooks frequently query the location of the object
database directory. Currently, this relies on legacy parsing methods or
manually inspecting `git rev-parse --git-path objects`.

Introduce `path.objects.absolute` and `path.objects.relative` keys to
`git repo info`. This allows tools to discover the object database
location safely while natively adhering to active `GIT_OBJECT_DIRECTORY`
environment variable overrides.

Mentored-by: Justin Tobler <jltobler@gmail.com>
Mentored-by: Lucas Seiki Oshiro <lucasseikioshiro@gmail.com>
Signed-off-by: K Jayatheerth <jayatheerthkulkarni2005@gmail.com>
---
 Documentation/git-repo.adoc |  9 +++++++++
 builtin/repo.c              | 24 ++++++++++++++++++++++++
 t/t1900-repo-info.sh        |  7 +++++++
 3 files changed, 40 insertions(+)

diff --git a/Documentation/git-repo.adoc b/Documentation/git-repo.adoc
index 03aa57942f..8429a44b43 100644
--- a/Documentation/git-repo.adoc
+++ b/Documentation/git-repo.adoc
@@ -119,6 +119,15 @@ values that they return:
 `path.gitdir.relative`::
 	The path to the Git repository directory relative to the current working directory.
 
+`path.objects.absolute`::
+	The canonical absolute path to the repository's object database directory.
+	Respects the `GIT_OBJECT_DIRECTORY` environment override.
+
+`path.objects.relative`::
+	The path to the repository's object database directory relative to the
+	current working directory. Respects the `GIT_OBJECT_DIRECTORY`
+	environment override.
+
 `path.superproject-working-tree.absolute`::
 	The canonical absolute path to the working tree root of the superproject
 	if the current repository is an initialized submodule. Outputs an empty
diff --git a/builtin/repo.c b/builtin/repo.c
index 82359473e9..d6bdd5bcfa 100644
--- a/builtin/repo.c
+++ b/builtin/repo.c
@@ -122,6 +122,28 @@ static int get_path_gitdir_relative(struct repository *repo, struct strbuf *buf)
 	return 0;
 }
 
+static int get_path_objects_absolute(struct repository *repo, struct strbuf *buf)
+{
+	const char *obj_dir = repo_get_object_directory(repo);
+
+	if (!obj_dir)
+		return error(_("unable to get object directory"));
+
+	format_path(buf, obj_dir, startup_info->prefix, PATH_FORMAT_CANONICAL);
+	return 0;
+}
+
+static int get_path_objects_relative(struct repository *repo, struct strbuf *buf)
+{
+	const char *obj_dir = repo_get_object_directory(repo);
+
+	if (!obj_dir)
+		return error(_("unable to get object directory"));
+
+	format_path(buf, obj_dir, startup_info->prefix, PATH_FORMAT_RELATIVE);
+	return 0;
+}
+
 static int get_path_superproject_absolute(struct repository *repo UNUSED, struct strbuf *buf)
 {
 	struct strbuf superproject = STRBUF_INIT;
@@ -194,6 +216,8 @@ static const struct repo_info_field repo_info_field[] = {
 	{ "path.commondir.relative", get_path_commondir_relative },
 	{ "path.gitdir.absolute", get_path_gitdir_absolute },
 	{ "path.gitdir.relative", get_path_gitdir_relative },
+	{ "path.objects.absolute", get_path_objects_absolute },
+	{ "path.objects.relative", get_path_objects_relative },
 	{ "path.superproject-working-tree.absolute", get_path_superproject_absolute },
 	{ "path.superproject-working-tree.relative", get_path_superproject_relative },
 	{ "path.toplevel.absolute", get_path_toplevel_absolute },
diff --git a/t/t1900-repo-info.sh b/t/t1900-repo-info.sh
index 220b3d4d3d..260f4fde43 100755
--- a/t/t1900-repo-info.sh
+++ b/t/t1900-repo-info.sh
@@ -213,6 +213,13 @@ test_repo_info_path 'gitdir with explicit GIT_DIR' 'gitdir' \
 	'.git' \
 	'GIT_DIR="../.git" && export GIT_DIR'
 
+test_repo_info_path 'objects standard' 'objects' '.git/objects'
+
+test_repo_info_path 'objects with GIT_OBJECT_DIRECTORY override' 'objects' \
+	'custom-objects' \
+	'GIT_OBJECT_DIRECTORY="$ROOT/custom-objects" && export GIT_OBJECT_DIRECTORY &&
+	 mkdir -p "$ROOT/custom-objects"'
+
 test_expect_success 'path.superproject-working-tree absolute and relative' '
 	test_when_finished "rm -rf sub super" &&
 	git init sub &&
-- 
2.55.GIT