diff --git a/test/test_configuration.py b/test/test_configuration.py
index ecbaeaf..ad50caf 100644
--- a/test/test_configuration.py
+++ b/test/test_configuration.py
@@ -2,7 +2,7 @@ from pathlib import Path
 
 import pytest
 
-from topen import OPTIONS, parse_cli, parse_env, parse_rc
+from topen import OPTIONS, TConf, parse_cli, parse_env, parse_rc
 
 
 class TestCli:
@@ -35,6 +35,8 @@ class TestCli:
 @pytest.fixture
 def isolate_env(monkeypatch):
     # delete all existing env vars that could interfere
+    monkeypatch.delenv("EDITOR", raising=False)
+    monkeypatch.delenv("VISUAL", raising=False)
     for opt in OPTIONS.values():
         if opt.env:
             monkeypatch.delenv(opt.env, raising=False)
@@ -86,3 +88,22 @@ class TestRcFile:
         assert rc_cfg["notes_annot"] == "Boo!"
         assert rc_cfg["notes_editor"] == "micro"
         assert rc_cfg["notes_quiet"] is True
+
+
+class TestTConf:
+    def test_paths_are_expanded(self):
+        cfg = TConf.from_dict(
+            {
+                "task_data": "~/somewhere/tasks",
+                "task_id": 0,
+                "task_rc": "$HOME/taskrc",
+                "notes_dir": "$HOME/notes",
+            }
+        )
+        assert cfg.task_data == Path("~/somewhere/tasks").expanduser()
+        assert cfg.task_rc == Path("~/taskrc").expanduser()
+        assert cfg.notes_dir == Path("~/notes").expanduser()
+
+    def test_default_notes_sub_dir(self):
+        cfg = TConf.from_dict({"task_data": "~/my/tasks", "task_id": 0})
+        assert cfg.notes_dir == Path("~/my/tasks/notes").expanduser()