chore: import upstream snapshot with attribution

dev/check_init_py.py

@@ -0,0 +1,54 @@
+"""
+Pre-commit hook to check for missing `__init__.py` files in mlflow and tests directories.
+
+This script ensures that all directories under the mlflow package and tests directory that contain
+Python files also have an `__init__.py` file. This prevents `setuptools` from excluding these
+directories during package build and ensures test modules are properly structured.
+
+Usage:
+    uv run dev/check_init_py.py
+
+Requirements:
+- If `mlflow/foo/bar.py` exists, `mlflow/foo/__init__.py` must exist.
+- If `tests/foo/test_bar.py` exists, `tests/foo/__init__.py` must exist.
+- Only test files (starting with `test_`) in the tests directory are checked.
+- All parent directories of Python files are checked recursively for `__init__.py`.
+- Ignore directories that do not contain any Python files (e.g., `mlflow/server/js`).
+"""
+
+import subprocess
+import sys
+from pathlib import Path
+
+
+def get_tracked_python_files() -> list[Path]:
+    try:
+        result = subprocess.check_output(
+            ["git", "ls-files", "mlflow/**/*.py", "tests/**/*.py"],
+            text=True,
+        )
+        paths = (Path(f) for f in result.splitlines() if f)
+        return [p for p in paths if (not p.is_relative_to("tests") or p.name.startswith("test_"))]
+    except subprocess.CalledProcessError as e:
+        print(f"Error running git ls-files: {e}", file=sys.stderr)
+        sys.exit(1)
+
+
+def main() -> int:
+    python_files = get_tracked_python_files()
+    if not python_files:
+        return 0
+
+    python_dirs = {p for f in python_files for p in f.parents if p != Path(".")}
+    if missing_init_files := [d for d in python_dirs if not (d / "__init__.py").exists()]:
+        print("Error: The following directories contain Python files but lack __init__.py:")
+        for d in sorted(missing_init_files):
+            print(f"  {d.as_posix()}/")
+        print("Please add __init__.py files to the directories listed above.")
+        return 1
+
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())