Brought Sort back into the repo

Decided that having a bunch of external dependencies would end up being more
trouble than it's worth

src/Sort.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * Sorting Utility Collection
+ *
+ * Licensed under The MIT License
+ * Redistribution of these files must retain the above copyright notice.
+ *
+ * @copyright Copyright 2007-2014, Josh Sherman
+ * @license   http://www.opensource.org/licenses/mit-license.html
+ * @link      http://picklesphp.com
+ * @package   Pickles
+ */
+
+namespace Pickles;
+
+/**
+ * Sort Class
+ *
+ * I got tired of writing separate usort functions to sort by different array
+ * keys in the array, this class solves that.
+ */
+class Sort
+{
+    /**
+     * Ascending
+     *
+     * Variable to utilize ascending sort
+     *
+     * @var integer
+     */
+    const ASC = 'ASC';
+
+    /**
+     * Descending
+     *
+     * Variable to utilize descending sort
+     *
+     * @var integer
+     */
+    const DESC = 'DESC';
+
+    /**
+     * Sort By
+     *
+     * Sorts an array by the specified column, optionally in either direction.
+     *
+     * @param string $field field to sort by
+     * @param array $array array to sort
+     * @param string $direction optional direction to sort
+     * @retun boolean true because sorting is done by reference
+     */
+    public static function by($field, &$array, $direction = Sort::ASC)
+    {
+        usort($array, create_function('$a, $b', '
+            $a = $a["' . $field . '"];
+            $b = $b["' . $field . '"];
+
+            if ($a == $b)
+            {
+                return 0;
+            }
+
+            return ($a ' . ($direction == Sort::DESC ? '>' : '<') .' $b) ? -1 : 1;
+        '));
+
+        return true;
+    }
+}
+

tests/Pickles/SortTest.php

@@ -0,0 +1,61 @@
+<?php
+
+class SortTest extends PHPUnit_Framework_TestCase
+{
+    public function testByNameASC()
+    {
+        $shuffled = [
+            ['name' => 'epsilon'],
+            ['name' => 'gamma'],
+            ['name' => 'alpha'],
+            ['name' => 'delta'],
+            ['name' => 'beta'],
+        ];
+
+        $sorted = [
+            ['name' => 'alpha'],
+            ['name' => 'beta'],
+            ['name' => 'delta'],
+            ['name' => 'epsilon'],
+            ['name' => 'gamma'],
+        ];
+
+        Pickles\Sort::by('name', $shuffled);
+
+        $this->assertEquals($sorted, $shuffled);
+    }
+
+    public function testByNameDESC()
+    {
+        $shuffled = [
+            ['name' => 'epsilon'],
+            ['name' => 'gamma'],
+            ['name' => 'alpha'],
+            ['name' => 'delta'],
+            ['name' => 'beta'],
+        ];
+
+        $sorted = [
+            ['name' => 'gamma'],
+            ['name' => 'epsilon'],
+            ['name' => 'delta'],
+            ['name' => 'beta'],
+            ['name' => 'alpha'],
+        ];
+
+        Pickles\Sort::by('name', $shuffled, Pickles\Sort::DESC);
+
+        $this->assertEquals($sorted, $shuffled);
+    }
+
+    public function testMissingField()
+    {
+        $shuffled = [['foo' => 'bar', 'bar' => 'foo']];
+        $sorted   = [['foo' => 'bar', 'bar' => 'foo']];
+
+        Pickles\Sort::by('name', $shuffled);
+
+        $this->assertEquals($sorted, $shuffled);
+    }
+}
+