It kinda depends. You could be "bulking" and gaining pounds of muscle and eating cake every meal and gaining pounds of fat too; opposed to gaining muscle and little fat on a good diet. I go be my lifts when i decide to cut.
Like A few months ago i set my goals to clean 265 and squat 450. And when i got there i started my cut. The goal of a bulk is to put on muscle. If you set goals in you lifts you know you've gained muscle when you reach them.