[GSoC Patch v4 0/4] teach git repo info to handle path keys

Hi!

This series teaches `git repo info` to handle `path.*` keys, allowing scripts to reliably discover core repository paths without resorting to `git rev-parse`.

The patches are structured as follows:

1. path: Extract the localized path-formatting logic
   out of `rev-parse` and expose it globally via
   `path.h` using clear append semantics.

2. rev-parse: Refactor the command to leverage the
   newly shared path engine.

3. repo: Introduce `path.commondir.absolute` and
   `path.commondir.relative` alongside a robust,
   isolated test helper.

4. repo: Introduce `path.gitdir.absolute` and
   `path.gitdir.relative` using the same standardized
   formatting rules.

Since all the questions were answered I have removed them from this cover letter.

Changes since v3:
* Removed unnecessary double quotes around the `..` argument when calling
  `test-tool path-utils real_path` in the `test_repo_info_path` helper,
  as suggested by Lucas.
* Retained the POSIX-compliant `ROOT="..." && export ROOT` syntax in the
  test setup. Combining them into `export ROOT="..."` triggered Git's
  strict `test-lint-shell-syntax` portability checks, so the separate
  assignment and export remains.

K Jayatheerth (4):
  path: introduce append_formatted_path() for shared path formatting
  rev-parse: use append_formatted_path() for path formatting
  repo: add path.commondir with absolute and relative suffix formatting
  repo: add path.gitdir with absolute and relative suffix formatting

 Documentation/git-repo.adoc |  15 ++++++
 builtin/repo.c              |  50 +++++++++++++++++
 builtin/rev-parse.c         | 103 ++++++++----------------------------
 path.c                      |  70 ++++++++++++++++++++++++
 path.h                      |  36 +++++++++++++
 t/t1900-repo-info.sh        |  68 ++++++++++++++++++++++++
 6 files changed, 262 insertions(+), 80 deletions(-)

Range-diff against v3:
1:  d276ac145e = 1:  a396b4f8e6 path: introduce append_formatted_path() for shared path formatting
2:  5dba41bcb3 = 2:  16198f96d1 rev-parse: use append_formatted_path() for path formatting
3:  b21c97f5d9 ! 3:  b45c6f0d12 repo: add path.commondir with absolute and relative suffix formatting
    @@ t/t1900-repo-info.sh: test_expect_success 'git repo info -h shows only repo info
     +	test_expect_success "absolute: $label" '
     +		(
     +			cd "$absolute_root/sub" &&
    -+			ROOT="$(test-tool path-utils real_path "..")" && export ROOT &&
    ++			ROOT="$(test-tool path-utils real_path ..)" && export ROOT &&
     +			eval "$init_command" &&
     +			expect_path="$ROOT${expect_absolute_suffix:+/$expect_absolute_suffix}" &&
     +			echo "path.$field_name.absolute=$expect_path" >expect &&
    @@ t/t1900-repo-info.sh: test_expect_success 'git repo info -h shows only repo info
     +	test_expect_success "relative: $label" '
     +		(
     +			cd "$relative_root/sub" &&
    -+			ROOT="$(test-tool path-utils real_path "..")" && export ROOT &&
    ++			ROOT="$(test-tool path-utils real_path ..)" && export ROOT &&
     +			eval "$init_command" &&
     +			echo "path.$field_name.relative=$expect_relative" >expect &&
     +			git repo info "path.$field_name.relative" >actual &&
4:  fd7a899788 = 4:  b5234ffe3e repo: add path.gitdir with absolute and relative suffix formatting