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Focal length, aperture and distance to subject all affect depth of field. We know from your post the focal length is 50 mm and aperture is f/1.2. At 10 feet, depth of field is .86 feet or just over 10 inches. At 5 feet, depth of field is .21 feet or just over 2 1/2 inches. I suppose the good news is your 7D has an APS-C sensor so you are apt to be further away from your subject than if you had a full frame body.
Time to get out your tripod and tape measure. Mount the camera a couple of feet from the floor, level. Stretch out the tape measure in front of it. Stand a book beside the tape measure to act as a target. Set the aperture to f/1.2. Take shots focusing on the book as you move the book from a couple of feet from the camera, a foot at a time, to about fifteen feet. Look at the tape measure in your photos, to see the depth of field. Let us know what you discover.