(comint-read-input-ring): Use ring-insert-at-beginning.

Insert most recent string first and only as many as we need.
Don't visit the file, just read it.

1 files changed, 17 insertions, 14 deletions

diff --git a/lisp/comint.el b/lisp/comint.el
index 286536574a8..010889678ff 100644
--- a/lisp/comint.el
+++ b/lisp/comint.el
@@ -616,27 +616,30 @@ See also `comint-input-ignoredups' and `comint-write-input-ring'."
              (message "Cannot read history file %s"
                       comint-input-ring-file-name)))
         (t
-         (let ((history-buf (get-file-buffer comint-input-ring-file-name))
+         (let ((history-buf (get-buffer-create " *temp*"))
+               (file comint-input-ring-file-name)
+               (count 0)
                (ring (make-ring comint-input-ring-size)))
-           (save-excursion
-             (set-buffer (or history-buf
-                             (find-file-noselect comint-input-ring-file-name)))
-             ;; Save restriction in case file is already visited...
-             ;; Watch for those date stamps in history files!
-             (save-excursion
-               (save-restriction
+           (unwind-protect
+               (save-excursion
+                 (set-buffer history-buf)
                  (widen)
-                 (goto-char (point-min))
-                 (while (re-search-forward "^[ \t]*\\([^#\n].*\\)[ \t]*$" nil t)
+                 (erase-buffer)
+                 (insert-file-contents file)
+                 ;; Save restriction in case file is already visited...
+                 ;; Watch for those date stamps in history files!
+                 (goto-char (point-max))
+                 (while (and (< count comint-input-ring-size)
+                             (re-search-backward "^[ \t]*\\([^#\n].*\\)[ \t]*$"
+                                                 nil t))
                    (let ((history (buffer-substring (match-beginning 1)
                                                     (match-end 1))))
                      (if (or (null comint-input-ignoredups)
                              (ring-empty-p ring)
                              (not (string-equal (ring-ref ring 0) history)))
-                         (ring-insert ring history)))))
-               ;; Kill buffer unless already visited.
-               (if (null history-buf)
-                   (kill-buffer nil))))
+                         (ring-insert-at-beginning ring history)))
+                   (setq count (1+ count))))
+             (kill-buffer history-buf))
            (setq comint-input-ring ring
                  comint-input-ring-index nil)))))