cygwin: skip ~root base dir test

Author: ThomasWaldmann

src/borg/testsuite/helpers/fs_test.py

@@ -22,7 +22,7 @@
     make_path_safe,
     map_chars,
 )
-from ...platform import is_win32, is_darwin, is_haiku
+from ...platform import is_win32, is_darwin, is_haiku, is_cygwin
 from .. import are_hardlinks_supported
 from .. import rejected_dotdot_paths
 
@@ -34,7 +34,7 @@ def test_get_base_dir(monkeypatch):
     monkeypatch.delenv("USER", raising=False)
     assert get_base_dir(legacy=True) == os.path.expanduser("~")
     # Haiku OS is a single-user OS, expanding "~root" is not supported.
-    if not is_haiku:
+    if not (is_haiku or is_cygwin):
         monkeypatch.setenv("USER", "root")
         assert get_base_dir(legacy=True) == os.path.expanduser("~root")
     monkeypatch.setenv("HOME", "/var/tmp/home")