fix error when creating a region in the 3rd automation track

Fixes https://todo.sr.ht/~alextee/zrythm-bug/872.

src/audio/region.c

@@ -560,6 +560,10 @@ TrackLane *
 region_get_lane (const ZRegion * self)
 {
   g_return_val_if_fail (IS_REGION (self), NULL);
+  g_return_val_if_fail (
+    self->id.type == REGION_TYPE_MIDI
+      || self->id.type == REGION_TYPE_AUDIO,
+    NULL);
 
   Track * track = arranger_object_get_track (
     (ArrangerObject *) self);

src/gui/backend/arranger_object.c

@@ -259,20 +259,46 @@ arranger_object_get_muted (
     check_parent
     && self->type == ARRANGER_OBJECT_TYPE_REGION)
     {
-      ZRegion *   region = (ZRegion *) self;
-      TrackLane * lane = region_get_lane (region);
-      g_return_val_if_fail (lane, true);
-      if (track_lane_get_muted (lane))
-        return true;
-
-      /* if lane is non-soloed while other soloed
-       * lanes exist, this should be muted */
-      Track * track = track_lane_get_track (lane);
-      g_return_val_if_fail (track, true);
-      if (
-        track_has_soloed_lanes (track)
-        && !track_lane_get_soloed (lane))
-        return true;
+      ZRegion * region = (ZRegion *) self;
+
+      switch (region->id.type)
+        {
+        case REGION_TYPE_MIDI:
+        case REGION_TYPE_AUDIO:
+          {
+            TrackLane * lane =
+              region_get_lane (region);
+            g_return_val_if_fail (lane, true);
+            if (track_lane_get_muted (lane))
+              return true;
+
+            /* if lane is non-soloed while other
+             * soloed lanes exist, this should be
+             * muted */
+            Track * track =
+              track_lane_get_track (lane);
+            g_return_val_if_fail (track, true);
+            if (
+              track_has_soloed_lanes (track)
+              && !track_lane_get_soloed (lane))
+              return true;
+          }
+          break;
+        case REGION_TYPE_AUTOMATION:
+          {
+            AutomationTrack * at =
+              region_get_automation_track (region);
+            g_return_val_if_fail (at, true);
+
+            if (
+              at->automation_mode
+              == AUTOMATION_MODE_OFF)
+              return true;
+          }
+          break;
+        default:
+          break;
+        }
     }
 
   return self->muted;

tests/audio/automation_track.c

@@ -67,6 +67,73 @@ test_set_at_index (void)
   test_helper_zrythm_cleanup ();
 }
 
+/**
+ * There was a case where
+ * arranger_object__get_muted() assumed
+ * that the region was an audio/MIDI region and
+ * threw errors.
+ *
+ * This replicates the issue and tests that this
+ * does not happen.
+ */
+static void
+test_region_in_2nd_automation_track_get_muted (void)
+{
+  test_helper_zrythm_init ();
+
+  Track * master = P_MASTER_TRACK;
+  track_set_automation_visible (master, true);
+  AutomationTracklist * atl =
+    track_get_automation_tracklist (master);
+  AutomationTrack ** visible_ats =
+    calloc (100000, sizeof (AutomationTrack *));
+  int num_visible = 0;
+  automation_tracklist_get_visible_tracks (
+    atl, visible_ats, &num_visible);
+  AutomationTrack * first_vis_at = visible_ats[0];
+
+  /* create a new automation track */
+  AutomationTrack * new_at =
+    automation_tracklist_get_first_invisible_at (
+      atl);
+  if (!new_at->created)
+    new_at->created = 1;
+  new_at->visible = true;
+
+  /* move it after the clicked
+   * automation track */
+  automation_tracklist_set_at_index (
+    atl, new_at, first_vis_at->index + 1, true);
+
+  /* create a region and set it as clip editor
+   * region */
+  Position start, end;
+  position_set_to_bar (&start, 2);
+  position_set_to_bar (&end, 4);
+  ZRegion * region = automation_region_new (
+    &start, &end, track_get_name_hash (master),
+    new_at->index, 0);
+  track_add_region (
+    master, region, new_at, -1, F_GEN_NAME,
+    F_NO_PUBLISH_EVENTS);
+  arranger_object_select (
+    (ArrangerObject *) region, F_SELECT,
+    F_NO_APPEND, F_NO_PUBLISH_EVENTS);
+  arranger_selections_action_perform_create (
+    (ArrangerSelections *) TL_SELECTIONS, NULL);
+
+  clip_editor_set_region (
+    CLIP_EDITOR, region, F_NO_PUBLISH_EVENTS);
+
+  engine_wait_n_cycles (AUDIO_ENGINE, 3);
+
+  /* assert not muted */
+  g_assert_false (arranger_object_get_muted (
+    (ArrangerObject *) region, true));
+
+  test_helper_zrythm_cleanup ();
+}
+
 int
 main (int argc, char * argv[])
 {
@@ -77,6 +144,11 @@ main (int argc, char * argv[])
   g_test_add_func (
     TEST_PREFIX "test set at index",
     (GTestFunc) test_set_at_index);
+  g_test_add_func (
+    TEST_PREFIX
+    "test region in 2nd automation track get muted",
+    (GTestFunc)
+      test_region_in_2nd_automation_track_get_muted);
 
   return g_test_run ();
 }