anchor.diff:    (setf (d (optional-import-message m)) 120)
   
     ;; repeated fields
  -  (let ((field-info *repeated-field-info*))
  -    (loop for (field . values) in field-info do
  -      (let ((accessor (field-function "" field))
  -            (v0 (first values))
  -            (v1 (second values)))
  -        (vector-push-extend v0 (funcall accessor m))
  -        (vector-push-extend v1 (funcall accessor m)))))
  +  (set-repeated-fields m *repeated-field-info*)
     (let ((v0 (make-instance 'test-all-types-repeated-group))
           (v1 (make-instance 'test-all-types-repeated-group)))
       (setf (a v0) 217)
  
positive.code:   (let ((package (find-package 'protobuf-unittest)))
      (fdefinition `(setf ,(find-symbol (symbol-name field) package)))))
  
  (defun expect-all-fields-set (m)
    ;; optional and default fields
    (let ((field-info (append *optional-field-info* *default-field-info*)))
  
negative.code:     (is (= (d (aref v 0)) 220))
      (is (= (d (aref v 1)) 320))))
  
  (defun read-message (class-name file-name)
    (let ((message (make-instance class-name)))
      (with-open-file (input file-name :direction :input :element-type 'unsigned-byte)
        (let* ((size (file-length input))
               (buffer (make-array size :element-type '(unsigned-byte 8))))
          (read-sequence buffer input)
          (pb:merge-from-array message buffer 0 size)))
      message))
  
  (deftest test-parse-from-file ()
    (let ((message (read-message 'test-all-types +golden-file-name+)))
      (expect-all-fields-set message)))
  
  (defvar *packed-field-info*
    ;; The values here must match those in *unpacked-field-info*.
    `((packed-int32 601 701) (packed-int64 602 702)
      (packed-uint32 603 703) (packed-uint64 604 704)
      (packed-sint32 605 705) (packed-sint64 606 706)
  