Move the calculation for item_related_update ahead of the duplicate

tag merge so that we don't trigger an item_related_update on items
who semantically have the same tag after the merge.  Follow-on for #1628.

1 files changed, 12 insertions, 10 deletions

diff --git a/modules/tag/models/tag.php b/modules/tag/models/tag.php
index bb79e707..d4e385a2 100644
--- a/modules/tag/models/tag.php
+++ b/modules/tag/models/tag.php
@@ -69,13 +69,24 @@ class Tag_Model_Core extends ORM {
    * to this tag.
    */
   public function save() {
+    // Figure out what items have changed in this tag for our item_related_update event below
+    if (isset($this->object_relations["items"])) {
+      $added = array_diff($this->changed_relations["items"], $this->object_relations["items"]);
+      $removed = array_diff($this->object_relations["items"], $this->changed_relations["items"]);
+      if (isset($this->changed_relations["items"])) {
+        $changed = array_merge($added, $removed);
+      }
+      $this->count = count($this->object_relations["items"]) + count($added) - count($removed);
+    }
+
     // Check to see if another tag exists with the same name
     $duplicate_tag = ORM::factory("tag")
       ->where("name", "=", $this->name)
       ->where("id", "!=", $this->id)
       ->find();
     if ($duplicate_tag->loaded()) {
-      // If so, tag its items with this tag so as to merge it
+      // If so, tag its items with this tag so as to merge it.  Do this after we figure out what's
+      // changed so that we don't notify on this change to keep churn down.
       $duplicate_tag_items = ORM::factory("item")
         ->join("items_tags", "items.id", "items_tags.item_id")
         ->where("items_tags.tag_id", "=", $duplicate_tag->id)
@@ -88,15 +99,6 @@ class Tag_Model_Core extends ORM {
       $duplicate_tag->delete();
     }
 
-    if (isset($this->object_relations["items"])) {
-      $added = array_diff($this->changed_relations["items"], $this->object_relations["items"]);
-      $removed = array_diff($this->object_relations["items"], $this->changed_relations["items"]);
-      if (isset($this->changed_relations["items"])) {
-        $changed = array_merge($added, $removed);
-      }
-      $this->count = count($this->object_relations["items"]) + count($added) - count($removed);
-    }
-
     $result = parent::save();
 
     if (!empty($changed)) {