Fix Repo() autodiscovery in linked worktrees when GIT_DIR is set

[meliezer]

Fixes #2022

This PR fixes repository autodiscovery in linked worktrees when GIT_DIR is set.

Summary

Fix Repo() autodiscovery when GIT_DIR points to a linked worktree git directory.

Previously, calling Repo() inside a linked worktree with GIT_DIR=$(git rev-parse --git-dir) could fail with InvalidGitRepositoryError, while Repo(os.getcwd()) resolved the repository correctly.

Changes

• add regression coverage for autodiscovery in linked worktrees when GIT_DIR is set
• detect linked worktree git directories during repository discovery
• derive the working tree directory correctly from the linked worktree metadata

Reproduction

Inside a linked worktree:

export GIT_DIR=$(git rev-parse --git-dir)
python -c "from git import Repo; Repo()"

Before: raises InvalidGitRepositoryError
After: resolves repository correctly

[Copilot]

Pull request overview

Fixes git.Repo() autodiscovery when invoked from within a linked worktree and GIT_DIR is set to that worktree’s internal git directory (e.g. .git/worktrees/<id>), preventing erroneous InvalidGitRepositoryError.

Changes:

• Added a regression test covering Repo() autodiscovery in a linked worktree with GIT_DIR set.
• Updated repository discovery to recognize linked-worktree git directories by their metadata files.
• Derived the correct working tree directory from linked worktree metadata during discovery.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
test/test_repo.py	Adds regression coverage ensuring Repo() works when GIT_DIR is set inside a linked worktree.
git/repo/base.py	Extends autodiscovery logic to detect linked-worktree git dirs and compute the correct working tree directory.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.