disallow to disable guard during focus

backend/tests/test_api.py

@@ -125,6 +125,36 @@ def test_invalid_settings_are_rejected(client):
     assert client.put("/api/settings", json={"timezone": "Mars/Olympus"}).status_code == 422
 
 
+def test_switching_the_guard_off_mid_interval_is_a_409(client):
+    assert client.put("/api/settings", json={"blocker": {"enabled": True}}).status_code == 200
+    client.post("/api/timer/start", json={"kind": "work"})
+
+    assert client.get("/api/blocker/policy").json()["locked"] is True
+
+    refused = client.put("/api/settings", json={"blocker": {"enabled": False}})
+    assert refused.status_code == 409
+    assert "focus guard" in refused.json()["detail"]
+
+    # Turning it on, and editing anything else, are both still fine.
+    assert client.put("/api/settings", json={"blocker": {"enabled": True}}).status_code == 200
+    lists = client.put("/api/settings", json={"blocker": {"blocked_apps": ["steam"]}})
+    assert lists.status_code == 200
+    assert lists.json()["settings"]["blocker"]["enabled"] is True
+
+    client.post("/api/timer/complete", json={"auto_next": False})
+    assert client.put("/api/settings", json={"blocker": {"enabled": False}}).status_code == 200
+
+
+def test_resetting_the_settings_cannot_unguard_a_live_interval(client):
+    client.put("/api/settings", json={"blocker": {"enabled": True}})
+    client.post("/api/timer/start", json={"kind": "short_break"})
+
+    assert client.post("/api/settings/reset").status_code == 409
+
+    client.post("/api/timer/complete", json={"auto_next": False})
+    assert client.post("/api/settings/reset").status_code == 200
+
+
 def test_notification_test_endpoint_falls_back_to_the_log(client):
     body = client.post("/api/notifications/test", json={}).json()
     assert body["deliveries"][0]["channel"] == "log"

backend/tests/test_blocker.py

@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+import pytest
 from app.services import blocker_service, pomodoro, settings_service
 
 
@@ -189,3 +190,179 @@ def test_the_policy_carries_the_allow_masks_for_the_stub(session, settings):
     assert result["allowed"] == ["music.youtube.com", "*.docs.google.com"]
     assert "music.youtube.com" not in result["domains"]
     assert "m.youtube.com" in result["all_domains"]
+
+
+# --------------------------------------------------------------------------
+# The lock: the guard will not be switched off mid-interval
+#
+# Only `apply_patch` and `reset_to_env` carry the check. `save_settings` stays an
+# unguarded low-level writer on purpose — the env seed, the password CLI and the
+# tests above all go through it — which is why these exercise the real write path.
+# --------------------------------------------------------------------------
+def _guarded(session, settings):
+    settings.blocker.enabled = True
+    settings_service.save_settings(session, settings)
+
+
+def test_the_guard_cannot_be_switched_off_while_an_interval_runs(session, settings):
+    _guarded(session, settings)
+    pomodoro.start(session, settings, kind="work")
+
+    with pytest.raises(blocker_service.GuardLocked):
+        settings_service.apply_patch(session, {"blocker": {"enabled": False}})
+
+    # And nothing was written on the way out.
+    assert settings_service.load_settings(session).blocker.enabled is True
+
+
+def test_pausing_is_not_an_escape_hatch(session, settings):
+    _guarded(session, settings)
+    pomodoro.start(session, settings, kind="work")
+    pomodoro.pause(session, settings)
+
+    with pytest.raises(blocker_service.GuardLocked):
+        settings_service.apply_patch(session, {"blocker": {"enabled": False}})
+
+
+@pytest.mark.parametrize("kind", ["short_break", "long_break"])
+@pytest.mark.parametrize("pause", [False, True])
+def test_a_break_is_not_an_escape_hatch_either(session, settings, kind, pause):
+    """The lock is kind-blind: `current_session` is the whole rule."""
+    _guarded(session, settings)
+    pomodoro.start(session, settings, kind=kind)
+    if pause:
+        pomodoro.pause(session, settings)
+
+    with pytest.raises(blocker_service.GuardLocked):
+        settings_service.apply_patch(session, {"blocker": {"enabled": False}})
+
+
+def test_the_guard_can_always_be_switched_on_mid_interval(session, settings):
+    pomodoro.start(session, settings, kind="work")
+    updated = settings_service.apply_patch(session, {"blocker": {"enabled": True}})
+    assert updated.blocker.enabled is True
+
+
+def test_the_guard_switches_off_freely_when_nothing_is_running(session, settings):
+    _guarded(session, settings)
+    updated = settings_service.apply_patch(session, {"blocker": {"enabled": False}})
+    assert updated.blocker.enabled is False
+
+
+def test_the_guard_switches_off_once_the_interval_is_over(session, settings):
+    _guarded(session, settings)
+    pomodoro.start(session, settings, kind="work")
+    pomodoro.complete(session, settings, auto_next=False)
+
+    updated = settings_service.apply_patch(session, {"blocker": {"enabled": False}})
+    assert updated.blocker.enabled is False
+
+
+def test_an_unrelated_blocker_patch_still_saves_mid_interval(session, settings):
+    """What the web app's list editor sends — the regression the check is shaped for."""
+    _guarded(session, settings)
+    pomodoro.start(session, settings, kind="work")
+
+    updated = settings_service.apply_patch(
+        session,
+        {"blocker": {"blocked_domains": ["youtube.com"], "blocked_apps": ["steam"]}},
+    )
+    assert updated.blocker.blocked_domains == ["youtube.com"]
+    assert updated.blocker.enabled is True
+
+
+def test_re_sending_an_already_off_guard_is_not_a_refusal(session, settings):
+    pomodoro.start(session, settings, kind="work")
+    updated = settings_service.apply_patch(session, {"blocker": {"enabled": False}})
+    assert updated.blocker.enabled is False
+
+
+def test_a_full_document_echo_survives_a_live_interval(session, settings):
+    _guarded(session, settings)
+    pomodoro.start(session, settings, kind="work")
+
+    echo = settings_service.load_settings(session).model_dump(mode="json")
+    updated = settings_service.apply_patch(session, echo)
+    assert updated.blocker.enabled is True
+
+
+def test_a_loosely_typed_off_is_still_an_off(session, settings):
+    """`{"enabled": "no"}` coerces to False, which is why the check compares
+    validated documents rather than reading the patch's keys."""
+    _guarded(session, settings)
+    pomodoro.start(session, settings, kind="work")
+
+    with pytest.raises(blocker_service.GuardLocked):
+        settings_service.apply_patch(session, {"blocker": {"enabled": "no"}})
+
+
+def test_the_policy_reports_the_lock(session, settings):
+    _guarded(session, settings)
+    assert blocker_service.policy(session, settings)["locked"] is False
+    assert blocker_service.policy(session, settings)["lock_reason"] == ""
+
+    pomodoro.start(session, settings, kind="work")
+    live = blocker_service.policy(session, settings)
+    assert live["locked"] is True
+    assert live["lock_reason"] == blocker_service.GUARD_LOCK_NOTE
+
+    pomodoro.pause(session, settings)
+    assert blocker_service.policy(session, settings)["locked"] is True
+
+
+def test_a_guard_that_is_off_is_never_reported_locked(session, settings):
+    """`locked` has "and the guard is on" folded in, so no client re-derives it."""
+    pomodoro.start(session, settings, kind="work")
+    assert blocker_service.policy(session, settings)["locked"] is False
+
+
+def test_the_policy_and_the_predicate_agree(session, settings):
+    """`policy()` re-expresses `guard_locked()` to reuse the row it already has;
+    these two must not drift."""
+    for enabled in (False, True):
+        settings.blocker.enabled = enabled
+        settings_service.save_settings(session, settings)
+        for kind in (None, "work", "short_break"):
+            if kind is not None:
+                pomodoro.start(session, settings, kind=kind)
+            assert blocker_service.policy(session, settings)["locked"] is (
+                blocker_service.guard_locked(session, settings)
+            )
+            if kind is not None:
+                pomodoro.abandon(session, settings, reason="test")
+
+
+def test_scheduled_mode_outside_its_window_is_inactive_and_still_locked(session, settings):
+    """The distinction `active` cannot express: nothing is blocked right now, and
+    the guard still must not be switched off before the window opens."""
+    settings.blocker.enabled = True
+    settings.blocker.mode = "scheduled"
+    settings.blocker.schedule = []
+    settings_service.save_settings(session, settings)
+    pomodoro.start(session, settings, kind="work")
+
+    result = blocker_service.policy(session, settings)
+    assert result["active"] is False
+    assert result["locked"] is True
+
+    with pytest.raises(blocker_service.GuardLocked):
+        settings_service.apply_patch(session, {"blocker": {"enabled": False}})
+
+
+def test_a_reset_cannot_switch_the_guard_off_mid_interval(session, settings):
+    """`settings_from_env` never touches the blocker subtree, so a reset always
+    lands on `enabled = False` — a second, quieter off-switch."""
+    _guarded(session, settings)
+    pomodoro.start(session, settings, kind="work")
+
+    with pytest.raises(blocker_service.GuardLocked):
+        settings_service.reset_to_env(session)
+    assert settings_service.load_settings(session).blocker.enabled is True
+
+    pomodoro.complete(session, settings, auto_next=False)
+    assert settings_service.reset_to_env(session).blocker.enabled is False
+
+
+def test_a_reset_is_fine_while_an_interval_runs_if_the_guard_is_off(session, settings):
+    pomodoro.start(session, settings, kind="work")
+    assert settings_service.reset_to_env(session).blocker.enabled is False