Add setIfExists() to Arr

src/Illuminate/Collections/Arr.php

@@ -796,6 +796,23 @@ public static function set(&$array, $key, $value)
         return $array;
     }
 
+    /**
+     * Set an array item to a given value using "dot" notation only if the array key exists
+     *
+     * @param  array  $array
+     * @param  string|int|null  $key
+     * @param  mixed  $value
+     * @return array
+     */
+    public static function setIfExists(&$array, $key, $value)
+    {
+        if (! static::exists($array, $key))) {
+            return $array;
+        }
+
+        return static::set($array, $key, $value);
+    }
+
     /**
      * Shuffle the given array and return the result.
      *

tests/Support/SupportArrTest.php

@@ -1040,6 +1040,19 @@ public function testSet()
         $this->assertEquals([1 => 'hAz'], Arr::set($array, 1, 'hAz'));
     }
 
+    public function testSetIfExists()
+    {
+        // key does not exist, nothing is set
+        $array = ['products' => ['desk' => ['price' => 100]]];
+        Arr::setIfExists($array, 'products.desk.currency', 'USD');
+        $this->assertEquals(['products' => ['desk' => ['price' => 100]]], $array);
+
+        // key exists
+        $array = ['products' => ['desk' => ['price' => 100]]];
+        Arr::setIfExists($array, 'products.desk.price', 200);
+        $this->assertEquals(['products' => ['desk' => ['price' => 200]]], $array);
+    }
+
     public function testShuffleProducesDifferentShuffles()
     {
         $input = range('a', 'z');