test: keep the CLI's saved selections out of the user's home (#1395)

- every test saves and reads CLI selections under its own tmp_path

tests/conftest.py

@@ -45,6 +45,12 @@ def _no_network(request, monkeypatch):
     monkeypatch.setattr(socket.socket, "connect_ex", refuse)
 
 
+@pytest.fixture(autouse=True)
+def _own_cli_prefs(tmp_path, monkeypatch):
+    """The CLI keeps the last run's selections in the user's home; tests keep theirs apart."""
+    monkeypatch.setattr("cli.prefs._PREFS_PATH", tmp_path / "cli_prefs.json")
+
+
 _API_KEY_ENV_VARS = (
     "OPENAI_API_KEY",
     "GOOGLE_API_KEY",

tests/test_cli_prefs.py

@@ -27,12 +27,6 @@ SAVED = {
 }
 
 
-@pytest.fixture(autouse=True)
-def _home(tmp_path, monkeypatch):
-    monkeypatch.setattr("cli.prefs._PREFS_PATH", tmp_path / "cli_prefs.json")
-    return tmp_path
-
-
 @pytest.mark.unit
 def test_round_trip():
     save_last_run(SAVED)
@@ -45,18 +39,18 @@ def test_missing_file_is_not_an_error():
 
 
 @pytest.mark.unit
-def test_a_corrupt_file_degrades_to_no_memory(_home):
-    (_home / "cli_prefs.json").write_text("{not json")
+def test_a_corrupt_file_degrades_to_no_memory(tmp_path):
+    (tmp_path / "cli_prefs.json").write_text("{not json")
     assert load_last_run() == {}
 
 
 @pytest.mark.unit
-def test_a_half_written_file_cannot_be_observed(_home):
+def test_a_half_written_file_cannot_be_observed(tmp_path):
     """Two runs finishing together must never leave a torn file behind."""
     save_last_run(SAVED)
     save_last_run({**SAVED, "research_depth": 5})
     assert load_last_run()["research_depth"] == 5
-    assert list((_home).glob("*.tmp*")) == []
+    assert list(tmp_path.glob("*.tmp*")) == []
 
 
 # --- validation against the current choices ---------------------------------

tests/test_suite_isolation.py

@@ -1,4 +1,4 @@
-"""The suite runs the same on any machine: no test reaches the network."""
+"""The suite runs the same on any machine: no test reaches the network or the user's files."""
 
 import socket
 
@@ -15,3 +15,15 @@ def test_a_test_cannot_reach_the_network(connect):
     machine it runs on; conftest refuses the connection instead."""
     with pytest.raises(OSError, match="reach the network"):
         connect()
+
+
+@pytest.mark.unit
+def test_a_test_saves_cli_selections_to_its_own_directory(tmp_path):
+    """The CLI remembers the last run's selections in the user's home; a test
+    that runs the selection flow would otherwise overwrite them."""
+    from cli import prefs
+
+    prefs.save_last_run({"analysts": ["market"]})
+
+    assert prefs._PREFS_PATH.is_relative_to(tmp_path)
+    assert prefs._PREFS_PATH.exists()