Optional callback for Arr::sort() (#21337)

src/Illuminate/Support/Arr.php

@@ -550,10 +550,10 @@ public static function shuffle($array)
      * Sort the array using the given callback or "dot" notation.
      *
      * @param  array  $array
-     * @param  callable|string  $callback
+     * @param  callable|string|null  $callback
      * @return array
      */
-    public static function sort($array, $callback)
+    public static function sort($array, $callback = null)
     {
         return Collection::make($array)->sortBy($callback)->all();
     }

src/Illuminate/Support/helpers.php

@@ -282,10 +282,10 @@ function array_set(&$array, $key, $value)
      * Sort the array by the given callback or attribute name.
      *
      * @param  array  $array
-     * @param  callable|string  $callback
+     * @param  callable|string|null  $callback
      * @return array
      */
-    function array_sort($array, $callback)
+    function array_sort($array, $callback = null)
     {
         return Arr::sort($array, $callback);
     }

tests/Support/SupportArrTest.php

@@ -510,6 +510,9 @@ public function testSort()
             ['name' => 'Desk'],
         ];
 
+        $sorted = array_values(Arr::sort($unsorted));
+        $this->assertEquals($expected, $sorted);
+
         // sort with closure
         $sortedWithClosure = array_values(Arr::sort($unsorted, function ($value) {
             return $value['name'];