with-file-temp-buffer: (FILENAME &rest BODY)

subr.el

(defmacro with-file-temp-buffer (filename &rest body)
  "Create a temporary buffer visiting FILENAME, and evaluate BODY there like
`progn'."
  (declare (indent 1) (debug t))
  (let* ((temp-buffer (make-symbol "temp-buffer")))
    `(let* ((truename (abbreviate-file-name (file-truename ,filename)))
            (number (nthcdr 10 (file-attributes truename)))
            (,temp-buffer (find-file-noselect-1
                           (create-file-buffer ,filename)
                           ,filename 'nowarn nil truename number)))
       (with-current-buffer ,temp-buffer
         (unwind-protect
             (progn ,@body)
           (and (buffer-name ,temp-buffer)
                (kill-buffer ,temp-buffer)))))))