rcrowe\Hippy\Message::setBackgroundColor PHP Method

    public function setBackgroundColor($color)
    {
        // throw exception here if not a valid color
        $this->background_color = $color;
    }

 public function testSet()
 {
     $message = new Message(false, 'random');
     $this->assertEquals($message->getBackgroundColor(), 'random');
     $message = new Message(false, 'red');
     $message->setBackgroundColor('random');
     $this->assertEquals($message->getBackgroundColor(), 'random');
 }