Skip symlink sibling test on Windows without symlink support

Author: Mulat Mekonen

testing/test_collection.py

@@ -1860,6 +1860,21 @@ def test_pyargs_collection_tree(pytester: Pytester, monkeypatch: MonkeyPatch) ->
     )
 
 
+def _can_create_symlink(tmp_path: Path) -> bool:
+    target = tmp_path / "target"
+    target.mkdir()
+    link = tmp_path / "link"
+    try:
+        os.symlink(target, link, target_is_directory=True)
+        return link.is_symlink()
+    except (OSError, NotImplementedError):
+        return False
+
+
+@pytest.mark.skipif(
+    sys.platform.startswith("win") and not _can_create_symlink(Path.cwd()),
+    reason="Windows without symlink support",
+)
 def test_do_not_collect_symlink_siblings(
     pytester: Pytester, tmp_path: Path, request: pytest.FixtureRequest
 ) -> None: