feat: show blocking alerts on the timetable even if they're low priority

lib/dotcom_web/templates/schedule/_timetable.html.eex

@@ -1,4 +1,4 @@
-<%= DotcomWeb.AlertView.group(alerts: @alerts, route: @route, date_time: @date_time, priority_filter: :high) %>
+<%= DotcomWeb.AlertView.group(alerts: @alerts, route: @route, date_time: @date_time, priority_filter: :high, always_show: List.wrap(@blocking_alert)) %>
 <%= render "_trip_view_filters.html", assigns %>
 
 <div class="calendar-covered m-timetable">

lib/dotcom_web/views/alert_view.ex

@@ -11,6 +11,8 @@ defmodule DotcomWeb.AlertView do
   alias Routes.Route
   alias Stops.Stop
 
+  @type priority_filter :: :any | Alerts.Priority.priority_level()
+
   @doc """
 
   Used to render a group of alerts.
@@ -28,6 +30,7 @@ defmodule DotcomWeb.AlertView do
       opts
       |> Keyword.fetch!(:alerts)
       |> Enum.filter(&filter_by_priority(priority_filter, &1))
+      |> then(&(Keyword.get(opts, :always_show, []) ++ &1))
       |> deduplicate()
 
     case {alerts, show_empty?} do
@@ -46,17 +49,8 @@ defmodule DotcomWeb.AlertView do
     end
   end
 
-  # Workaround handling duplicate Red Line alerts for JFK-Ashmont shuttle
   defp deduplicate(alerts) do
-    alert_ids = Enum.map(alerts, & &1.id)
-    ashmont_shuttle_alert_ids = ["519314", "529291"]
-
-    if Enum.all?(ashmont_shuttle_alert_ids, &Enum.member?(alert_ids, &1)) do
-      # remove the second one
-      Enum.reject(alerts, &(&1.id == "529291"))
-    else
-      alerts
-    end
+    Enum.uniq_by(alerts, & &1.id)
   end
 
   @spec no_alerts_message(map, boolean, atom) :: iolist
@@ -129,14 +123,17 @@ defmodule DotcomWeb.AlertView do
       " at this time."
     ]
 
-  @spec filter_by_priority(boolean, Alert.t()) :: boolean
-  defp filter_by_priority(:any, _), do: true
+  @spec filter_by_priority(
+          priority_filter,
+          Alert.t()
+        ) :: boolean
+  defp filter_by_priority(:any, _alert), do: true
 
   defp filter_by_priority(priority_filter, %{priority: priority})
-       when priority_filter == priority,
+       when is_atom(priority_filter) and priority_filter == priority,
        do: true
 
-  defp filter_by_priority(_, _), do: false
+  defp filter_by_priority(_filter, _alert), do: false
 
   def effect_name(%{lifecycle: lifecycle} = alert)
       when lifecycle in [:new, :unknown] do

test/dotcom_web/views/alert_view_test.exs

@@ -188,7 +188,7 @@ defmodule DotcomWeb.AlertViewTest do
 
     test "text for an CR alert which is blocking the timetable (but has a PDF available)" do
       alert = %Alerts.Alert{
-        header: "Blocked timetable. View PDF Timetable on the MBTA website.",
+        header: "Blocked timetable. #{Dotcom.TimetableBlocking.pdf_available_text()}",
         url: "https://www.mbta.com/pdf-timetable",
         updated_at: DateTime.utc_now()
       }
@@ -208,6 +208,74 @@ defmodule DotcomWeb.AlertViewTest do
       assert text =~ ~s["https://www.mbta.com/pdf-timetable"]
       assert text =~ ">View PDF Timetable</a>"
     end
+
+    test "shows a blocking alert even if it's low priority" do
+      alert =
+        Alerts.Alert.new(
+          header: "Blocked timetable. #{Dotcom.TimetableBlocking.no_pdf_text()}",
+          priority: :low,
+          updated_at: DateTime.utc_now(),
+          informed_entity: [%Alerts.InformedEntity{route: @route.id}],
+          active_period: [{~U[2025-01-01T00:00:00Z], nil}]
+        )
+
+      response =
+        group(
+          alerts: [alert],
+          route: @route,
+          date_time: DateTime.utc_now(),
+          priority_filter: :high,
+          always_show: [alert]
+        )
+
+      text = safe_to_string(response)
+      assert text =~ "Blocked timetable."
+    end
+
+    test "shows a blocking alert only once" do
+      alert =
+        Alerts.Alert.new(
+          header: "Blocked timetable. #{Dotcom.TimetableBlocking.no_pdf_text()}",
+          priority: :low,
+          updated_at: DateTime.utc_now(),
+          informed_entity: [%Alerts.InformedEntity{route: @route.id}],
+          active_period: [{~U[2025-01-01T00:00:00Z], nil}]
+        )
+
+      response =
+        group(
+          alerts: [alert],
+          route: @route,
+          date_time: DateTime.utc_now(),
+          always_show: [alert]
+        )
+
+      text = safe_to_string(response)
+      # only one copy of the alert
+      assert [_] = Regex.scan(~r/Blocked timetable/, text)
+    end
+
+    test "does not show a blocking alert on the wrong date" do
+      alert =
+        Alerts.Alert.new(
+          header: "Blocked timetable. #{Dotcom.TimetableBlocking.no_pdf_text()}",
+          priority: :low,
+          updated_at: DateTime.utc_now(),
+          informed_entity: [%Alerts.InformedEntity{route: @route.id}],
+          active_period: [{~U[2025-02-02T00:00:00Z], nil}]
+        )
+
+      response =
+        group(
+          alerts: [alert],
+          route: @route,
+          date_time: DateTime.utc_now(),
+          priority_filter: :high,
+          always_show: []
+        )
+
+      assert response == ""
+    end
   end
 
   describe "no_alerts_message/3" do