fix: expose the release version in editable imports

Salt parses `git.__version__` when enabling its GitPython provider. Source
imports retain the build placeholder `"git"`, so an editable installation
reports valid distribution metadata but Salt rejects the provider and skips
its real fileserver tests.

Read the checkout's `VERSION` only when the public value is still unstamped.
Built wheels and source distributions continue to use the existing release
stamping; repository discovery and backend selection are unchanged.

The regression failed with `"git"` before this change. All 34 downstream
compatibility regressions pass with both CLI and Gix. Ruff lint/format,
mypy for `git/__init__.py`, and `git diff --check` pass.

Author: codex

doc/source/changes.rst

@@ -51,6 +51,9 @@ Git executable and safety
 API changes
 -----------
 
+* Editable/source imports expose the release version in ``git.__version__``,
+  matching built distributions. Salt's GitPython provider checks can parse the
+  version instead of rejecting the unstamped ``"git"`` build placeholder.
 * ``Repo`` construction validates repository configuration through Git/Gix.
   A subclass override of ``config_reader()`` no longer controls discovery or
   suppresses its include graph. Malformed configuration and invalid repository

git/__init__.py

@@ -81,6 +81,11 @@
 ]
 
 __version__ = "git"
+if __version__ == "git":
+    # Wheels and source distributions stamp this value; editable imports do not.
+    from pathlib import Path as _Path
+
+    __version__ = (_Path(__file__).resolve().parents[1] / "VERSION").read_text(encoding="utf-8").strip()
 
 from typing import Optional as _Optional
 

test/test_downstream_compatibility.py

@@ -1,6 +1,7 @@
 """Public GitPython queries used by released downstream projects."""
 
 from pathlib import Path
+from importlib.metadata import version
 
 import pytest
 
@@ -10,6 +11,10 @@
 from test.lib.fixtures import fixture_repo, read_only_fixture
 
 
+def test_public_version_supports_downstream_provider_checks():
+    assert git.__version__ == version("GitPython")
+
+
 @pytest.mark.parametrize("object_format", ["sha1", "sha256"])
 @pytest.mark.parametrize("ref_format", ["files", "reftable"])
 def test_repo_accepts_explicit_literal_path_selection(object_format, ref_format, monkeypatch):