pathlib: inline ensure_reset_dir()

This is only used in TempPathFactory.getbasetemp(). We'll be wanting
further control/care there, so move it into there.

src/_pytest/pathlib.py

@@ -64,13 +64,6 @@ def get_lock_path(path: _AnyPurePath) -> _AnyPurePath:
     return path.joinpath(".lock")
 
 
-def ensure_reset_dir(path: Path) -> None:
-    """Ensure the given path is an empty directory."""
-    if path.exists():
-        rm_rf(path)
-    path.mkdir()
-
-
 def on_rm_rf_error(func, path: str, exc, *, start_path: Path) -> bool:
     """Handle known read-only errors during rmtree.
 

src/_pytest/tmpdir.py

@@ -8,10 +8,10 @@
 import attr
 import py
 
-from .pathlib import ensure_reset_dir
 from .pathlib import LOCK_TIMEOUT
 from .pathlib import make_numbered_dir
 from .pathlib import make_numbered_dir_with_cleanup
+from .pathlib import rm_rf
 from _pytest.compat import final
 from _pytest.config import Config
 from _pytest.deprecated import check_ispytest
@@ -103,7 +103,9 @@ def getbasetemp(self) -> Path:
 
         if self._given_basetemp is not None:
             basetemp = self._given_basetemp
-            ensure_reset_dir(basetemp)
+            if basetemp.exists():
+                rm_rf(basetemp)
+            basetemp.mkdir()
             basetemp = basetemp.resolve()
         else:
             from_env = os.environ.get("PYTEST_DEBUG_TEMPROOT")