public function test_extend()
{
$array1 = ['foo' => ['a' => 'b', 'bar' => [1, 2, 3]]];
$array2 = ['foo' => ['x' => 'y', 'bar' => [5]]];
$config1 = new Config($array1);
$config2 = new Config($array2);
$config1->extend($config2);
$this->assertEquals(['foo' => ['a' => 'b', 'x' => 'y', 'bar' => [5]]], $config1->toArray());
}
