Some question about code line count when sign GPL paper

[tumashu]

* Case 1

** I have a function in my package.
(defun test1 ()
  (let ((a 1)
        (b 2)
        (c 3)
        (d 4)
        (e 5))
    (print "test1")))


** Contributer add another new function which is very similar test1. 

(defun test2 ()            
  (let ((a 1)
        (b 2)
        (c 3)
        (d 4)
        (e 5))
    (print "test2")))  ;; the only different line from test1


should I count this countribution 7 lines or 1 line?

* Case2

If I can't let a contributer to sign GPL paper, How should I do:

1. just rewrite or revert his code and do not need to wash repo history?
2. remove his commit, by wash repo history?