get_project_name_from_dir() only reads Path.name — it never touches the filesystem. Tests were unnecessarily creating real directories via tmp_path, which fails on Windows where "..." is interpreted as ../.. traversal and trailing dots are silently stripped.

• tests/usethis/_file/test_dir.py: Replace all tmp_path-based paths with string paths ("/fake/...") since no filesystem access is needed
• usethis-python-test skill (v1.5 → v1.6): Add guidance on preferring synthetic paths when testing pure path-metadata logic

# Before: fails on Windows when dir_name is OS-special
def test_leading_dots(self, tmp_path: Path):
    with usethis_config.set(project_dir=tmp_path / "..hidden"):
        assert get_project_name_from_dir() == "hidden"

# After: no filesystem dependency
def test_leading_dots(self):
    with usethis_config.set(project_dir="/fake/..hidden"):
        assert get_project_name_from_dir() == "hidden"