more work on config tests

tests/test_base.py

@@ -8,7 +8,16 @@
 from wagstails import MondoData
 
 
-def test_config_directory_basic(base_data_dir: Path):
+@pytest.fixture(scope="function")
+def config_teardown():
+    """Make sure environment variables are unset after running `test_config_directory`"""
+    yield
+    for varname in ("XDG_DATA_DIRS", "XDG_DATA_HOME", "WAGSTAILS_DIR"):
+        if varname in os.environ:
+            del os.environ[varname]
+
+
+def test_config_directory(base_data_dir: Path):
     """Basic tests of directory configuration that shouldn't affect non-temporary files."""
     m = MondoData(base_data_dir)
     assert m._data_dir == base_data_dir
@@ -35,8 +44,12 @@ def test_config_directory_basic(base_data_dir: Path):
 @pytest.mark.skipif(
     os.environ.get("WAGSTAILS_TEST_ENV", "").lower() != "true", reason="Not in CI"
 )
-def test_config_directory_advanced():
-    """Test running from a totally clean environment (i.e. CI)"""
+def test_default_directory_configs():
+    """Test default directory in ~/.local/share
+
+    Since this could affects things outside of the immediate code repo, this test
+    should mainly run in CI, where we can guarantee a clean user environment.
+    """
     m = MondoData()
     assert m._data_dir == Path.home() / ".local" / "share" / "wagstails" / "mondo"
     assert m._data_dir.exists() and m._data_dir.is_dir()