public function testReturnsNullWhenMergingNonArray()
{
$t = new TreeInterpreter();
$this->assertNull($t->visit(array('type' => 'flatten', 'children' => array(array('type' => 'literal', 'value' => 1), array('type' => 'literal', 'value' => 1))), array(), array('runtime' => new AstRuntime())));
}
