Add unittest and caching to ORM_MTPP::descendants_count

2 files changed, 28 insertions, 9 deletions

diff --git a/core/libraries/ORM_MPTT.php b/core/libraries/ORM_MPTT.php
index 5cdf9c02..c9c29805 100644
--- a/core/libraries/ORM_MPTT.php
+++ b/core/libraries/ORM_MPTT.php
@@ -37,6 +37,7 @@ class ORM_MPTT_Core extends ORM {
   private $parents = null;
   private $children = null;
   private $children_count = null;
+  private $descendants_count = array();
 
   function __construct($id=null) {
     parent::__construct($id);
@@ -165,19 +166,18 @@ class ORM_MPTT_Core extends ORM {
    * @return   integer  child count
    */
   function descendants_count($type=null) {
-    // @todo create a unit test
-    // @todo set up caching in an array;; using type=all allows us to cache as decendents[$type]
-    $this->where("left >=", $this->left)
-      ->where("right <=", $this->right);
-    if ($type) {
-      $this->where("type", $type);
+    if (!isset($this->descendants_count[$type])) {
+      $this->where("left >", $this->left)
+        ->where("right <=", $this->right);
+      if ($type) {
+        $this->where("type", $type);
+      }
+      $this->descendants_count[$type] = $this->count_all();
     }
 
-    // @todo does it make sense to order it before counting?
-    return $this->count_all();
+    return $this->descendants_count[$type];
   }
 
-
   /**
    * @see ORM::reload
    */
diff --git a/core/tests/ORM_MPTT_Test.php b/core/tests/ORM_MPTT_Test.php
index d66006f5..a053b61e 100644
--- a/core/tests/ORM_MPTT_Test.php
+++ b/core/tests/ORM_MPTT_Test.php
@@ -94,4 +94,23 @@ class ORM_MPTT_Test extends Unit_Test_Case {
     $inner2->add_to_parent($outer->id);
     $this->assert_equal(2, $outer->children_count());
   }
+
+  public function descendant_count_test() {
+    $parent = album::create(1, "parent album", "parent album title");
+    photo::create($parent->id, DOCROOT . "themes/default/images/thumbnail.jpg", "photo1", 
+                  "photo1", "parent album photo");
+
+    $album1 = album::create($parent->id, "album1", "album1 title");
+    photo::create($album1->id, DOCROOT . "themes/default/images/thumbnail.jpg", "photo1", 
+                  "photo1", "album1 photo");
+
+    $album2 = album::create($parent->id, "album2", "album2 title");
+    photo::create($album2->id, DOCROOT . "themes/default/images/thumbnail.jpg", "photo2", 
+                  "photo2", "album2 photo");
+    $parent->reload();
+
+    $this->assert_equal(5, $parent->descendants_count());
+    $this->assert_equal(3, $parent->descendants_count("photo"));
+    $this->assert_equal(2, $parent->descendants_count("album"));
+  }
 }