search: Fold recurring events into single results

When searching for events, users are typically interested in finding the
event rather than seeing a repetitive list of every occurrence instance.
By configuring the search timelines with "expand-recurrences" set to FALSE,
recurring events are loaded as their single master component instead of
expanding all individual occurrences.

Additionally:
- Update GcalSearchHitEvent subtitle to display "Recurring" (e.g. "Tomorrow • Recurring"
  or "Recurring") when the event has a recurrence rule.
- Safeguard gcal_event_format_date() when running without a default GApplication.

Fixes: https://gitlab.gnome.org/GNOME/gnome-calendar/-/issues/991
Part-of: <https://gitlab.gnome.org/GNOME/gnome-calendar/-/merge_requests/808>

src/core/gcal-event.c

@@ -1911,8 +1911,15 @@ gcal_event_format_date (GcalEvent *self)
 
   /* XXX: nasty... */
   application = GCAL_APPLICATION (g_application_get_default ());
-  context = gcal_application_get_context (application);
-  time_format = gcal_context_get_time_format (context);
+  if (application)
+    {
+      context = gcal_application_get_context (application);
+      time_format = gcal_context_get_time_format (context);
+    }
+  else
+    {
+      time_format = GCAL_TIME_FORMAT_24H;
+    }
 
   if (time_format == GCAL_TIME_FORMAT_24H)
     hour_format = "%R";

src/core/gcal-shell-search-provider.c

@@ -474,7 +474,9 @@ gcal_shell_search_provider_constructed (GObject *object)
   GcalContext *context = gcal_application_get_context (GCAL_DEFAULT_APPLICATION);
   GcalManager *manager = gcal_context_get_manager (context);
 
-  self->timeline = gcal_timeline_new ();
+  self->timeline = g_object_new (GCAL_TYPE_TIMELINE,
+                                 "expand-recurrences", FALSE,
+                                 NULL);
   g_signal_connect (self->timeline, "notify::complete", G_CALLBACK (on_timeline_completed_cb), self);
 
   g_signal_connect (manager, "calendar-added", G_CALLBACK (on_manager_calendar_added_cb), self);

src/search/gcal-search-engine.c

@@ -113,7 +113,9 @@ gcal_search_engine_constructed (GObject *object)
   G_OBJECT_CLASS (gcal_search_engine_parent_class)->constructed (object);
 
   /* Set up the data model */
-  self->timeline = gcal_timeline_new ();
+  self->timeline = g_object_new (GCAL_TYPE_TIMELINE,
+                                 "expand-recurrences", FALSE,
+                                 NULL);
 
   context = gcal_application_get_context (GCAL_DEFAULT_APPLICATION);
   manager = gcal_context_get_manager (context);

src/search/gcal-search-hit-event.c

@@ -24,6 +24,8 @@
 #include "gcal-search-hit-event.h"
 #include "gcal-utils.h"
 
+#include <glib/gi18n.h>
+
 struct _GcalSearchHitEvent
 {
   GcalSearchHit       parent;
@@ -63,9 +65,22 @@ set_event (GcalSearchHitEvent *self,
   gcal_search_hit_set_title (search_hit, gcal_event_get_summary (event));
 
   date_string = gcal_event_format_date (event);
+
+  if (gcal_event_has_recurrence (event))
+    {
+      g_autofree gchar *formatted_date = g_steal_pointer (&date_string);
+
+      if (formatted_date && *formatted_date != '\0')
+        date_string = g_strdup_printf (_ ("%s • Recurring"), formatted_date);
+      else
+        date_string = g_strdup (_ ("Recurring"));
+    }
+
   gcal_search_hit_set_subtitle (search_hit, date_string);
 
   calendar = gcal_event_get_calendar (self->event);
+  g_assert (calendar != NULL);
+
   color = gcal_calendar_get_color (calendar);
   paintable = gcal_util_get_circle_paintable_from_color (color, 16);
   gcal_search_hit_set_primary_icon (search_hit, paintable);