fix timers

backend/tests/test_api.py

@@ -29,6 +29,28 @@ def test_a_whole_pomodoro_through_the_api(client):
     assert "Daily report" in report["telegram_preview"]
 
 
+def test_a_stale_complete_leaves_the_auto_started_break_alone(client):
+    client.put(
+        "/api/settings",
+        json={"pomodoro": {"auto_start_breaks": True, "auto_start_work": True}},
+    )
+    state = client.post("/api/timer/start", json={"kind": "work"}).json()
+    work_id = state["current"]["id"]
+
+    done = client.post(
+        "/api/timer/complete", json={"auto_next": True, "session_id": work_id}
+    ).json()
+    assert done["current"]["kind"] in ("short_break", "long_break")
+    break_id = done["current"]["id"]
+
+    # The other client's countdown, one beat behind.
+    again = client.post(
+        "/api/timer/complete", json={"auto_next": True, "session_id": work_id}
+    ).json()
+    assert again["finished"] is None
+    assert again["current"]["id"] == break_id
+
+
 def test_timer_errors_are_400_not_500(client):
     assert client.post("/api/timer/pause").status_code == 400
     assert client.post("/api/timer/complete", json={}).status_code == 400