From e9e7655867152d55fc3d83635cc427b25f0d895a Mon Sep 17 00:00:00 2001
From: Sam Minnee <sam@silverstripe.com>
Date: Fri, 9 Mar 2012 14:28:14 +1300
Subject: [PATCH] API CHANGE: Added SS_Sortable, an extra interface to apply to
 SS_Lists.

---
 model/ArrayList.php     |  2 +-
 model/DataList.php      |  2 +-
 model/ListDecorator.php |  2 +-
 model/Sortable.php      | 29 +++++++++++++++++++++++++++++
 4 files changed, 32 insertions(+), 3 deletions(-)
 create mode 100644 model/Sortable.php

diff --git a/model/ArrayList.php b/model/ArrayList.php
index 1de211f40..fe7bd91f2 100644
--- a/model/ArrayList.php
+++ b/model/ArrayList.php
@@ -5,7 +5,7 @@
  * @package    sapphire
  * @subpackage model
  */
-class ArrayList extends ViewableData implements SS_List, SS_Filterable, SS_Limitable {
+class ArrayList extends ViewableData implements SS_List, SS_Filterable, SS_Sortable, SS_Limitable {
 
 	/**
 	 * Holds the items in the list
diff --git a/model/DataList.php b/model/DataList.php
index bb9e2bfa4..92af851e1 100644
--- a/model/DataList.php
+++ b/model/DataList.php
@@ -6,7 +6,7 @@
  * @package    sapphire
  * @subpackage model
  */
-class DataList extends ViewableData implements SS_List, SS_Filterable, SS_Limitable {
+class DataList extends ViewableData implements SS_List, SS_Filterable, SS_Sortable, SS_Limitable {
 	/**
 	 * The DataObject class name that this data list is querying
 	 * 
diff --git a/model/ListDecorator.php b/model/ListDecorator.php
index 46efb202b..53da6a0a0 100644
--- a/model/ListDecorator.php
+++ b/model/ListDecorator.php
@@ -7,7 +7,7 @@
  * @package    sapphire
  * @subpackage model
  */
-abstract class SS_ListDecorator extends ViewableData implements SS_List, SS_Filterable, SS_Limitable {
+abstract class SS_ListDecorator extends ViewableData implements SS_List, SS_Sortable, SS_Filterable, SS_Limitable {
 
 	protected $list;
 
diff --git a/model/Sortable.php b/model/Sortable.php
new file mode 100644
index 000000000..e916f3529
--- /dev/null
+++ b/model/Sortable.php
@@ -0,0 +1,29 @@
+<?php
+
+/**
+ * Additional interface for {@link SS_List} classes that are sortable.
+ * 
+ * @see SS_List, SS_Filterable, SS_Limitable
+ */
+interface SS_Sortable {
+
+	/**
+	 * Returns TRUE if the list can be sorted by a field.
+	 *
+	 * @param  string $by
+	 * @return bool
+	 */
+	public function canSortBy($by);
+
+	/**
+	 * Sorts this list by one or more fields. You can either pass in a single
+	 * field name and direction, or a map of field names to sort directions.
+	 *
+	 * @example $list->sort('Name'); // default ASC sorting
+	 * @example $list->sort('Name DESC'); // DESC sorting
+	 * @example $list->sort('Name', 'ASC');
+	 * @example $list->sort(array('Name'=>'ASC,'Age'=>'DESC'));
+	 */
+	public function sort();
+	
+}
\ No newline at end of file