public function testIsMutable()
{
$arguments = [$arg0 = new \stdClass()];
$definition = new SimpleMethodCall('foo', $arguments);
// Mutate before reading values
$arg0->foo = 'bar';
// Mutate retrieved values
$definition->getArguments()[0]->foz = 'baz';
$this->assertEquals([StdClassFactory::create(['foo' => 'bar', 'foz' => 'baz'])], $definition->getArguments());
}