Merge pull request #1363 from franzliedke/patch-55

Many-to-many sync: always work with arrays

laravel/database/eloquent/relationships/has_many_and_belongs_to.php

@@ -121,6 +121,7 @@ class Has_Many_And_Belongs_To extends Relationship {
 	public function sync($ids)
 	{
 		$current = $this->pivot()->lists($this->other_key());
+		$ids = (array) $ids;
 
 		// First we need to attach any of the associated models that are not currently
 		// in the joining table. We'll spin through the given IDs, checking to see
@@ -140,7 +141,7 @@ class Has_Many_And_Belongs_To extends Relationship {
 
 		if (count($detach) > 0)
 		{
-			$this->detach(array_diff($current, $ids));
+			$this->detach($detach);
 		}
 	}