add 'tmp_west_topdir' function for usage in tests

This helper function for tests is added. It temporarily creates a west
topdir for the duration of the `with` block by creating a .west
directory at given path. The diectory is removed again when the `with`
block exits.

Author: thorsten-klein

tests/conftest.py

@@ -68,6 +68,22 @@
 #
 
 
+@contextlib.contextmanager
+def tmp_west_topdir(path: str | Path):
+    """
+    Temporarily create a west topdir for the duration of the `with` block by
+    creating a .west directory at given path. The directory is removed again
+    when the `with` block exits.
+    """
+    west_dir = Path(path) / '.west'
+    west_dir.mkdir(parents=True)
+    try:
+        yield
+    finally:
+        # remove the directory (must be empty)
+        west_dir.rmdir()
+
+
 @contextlib.contextmanager
 def update_env(env: dict[str, str | None]):
     """