public function testArraySeparateWithUndefinedIndexes()
 {
     $array = [1 => 'January', 2 => 'February', 3 => 'March', 4 => 'April'];
     $keys = [5, 6];
     $result = array_separate($array, $keys);
     assertThat($result, is(emptyArray()));
     assertThat(count($array), is(equalTo(4)));
 }
 /**
  * Separates attributes for PostMeta models from Gallery attributes.
  *
  * @param  array  $attributes
  * @return void
  */
 protected function filterMetaAttributes(array &$attributes)
 {
     static::$metaAttributes = array_separate($attributes, $this->metaKeys);
 }