PopTest\Color\ColorTest::testRgbToCmyk PHP Method

    public function testRgbToCmyk()
    {
        $cmyk = Convert::toCmyk(new Rgb(0, 0, 0));
        $this->assertInstanceOf('Pop\\Color\\Space\\Cmyk', $cmyk);
        $this->assertEquals('0,0,0,100', (string) $cmyk);
    }