+ (if (and grp (not (string= "" grp))
+ (gnus-methods-equal-p gnus-command-method
+ (nnmail-cache-primary-mail-backend)))
+ (let ((regexp (if (consp nnmail-cache-ignore-groups)
+ (mapconcat 'identity nnmail-cache-ignore-groups
+ "\\|")
+ nnmail-cache-ignore-groups)))
+ (unless (and regexp (string-match regexp grp))
+ (insert id "\t" grp "\n")))
+ (insert id "\n")))))
+
+(defun nnmail-cache-primary-mail-backend ()
+ (let ((be-list (cons gnus-select-method gnus-secondary-select-methods))
+ (be nil)
+ (res nil))
+ (while (and (null res) be-list)
+ (setq be (car be-list))
+ (setq be-list (cdr be-list))
+ (when (and (gnus-method-option-p be 'respool)
+ (eval (intern (format "%s-get-new-mail" (car be)))))
+ (setq res be)))
+ res))
+
+;; Fetch the group name corresponding to the message id stored in the
+;; cache.
+(defun nnmail-cache-fetch-group (id)
+ (when (and nnmail-treat-duplicates nnmail-cache-buffer)
+ (save-excursion
+ (set-buffer nnmail-cache-buffer)
+ (goto-char (point-max))
+ (when (search-backward id nil t)
+ (beginning-of-line)
+ (skip-chars-forward "^\n\r\t")
+ (unless (looking-at "[\r\n]")
+ (forward-char 1)
+ (buffer-substring (point)
+ (progn (end-of-line) (point))))))))
+
+;; Function for nnmail-split-fancy: look up all references in the
+;; cache and if a match is found, return that group.
+(defun nnmail-split-fancy-with-parent ()
+ "Split this message into the same group as its parent.
+This function can be used as an entry in `nnmail-split-fancy', for
+example like this: (: nnmail-split-fancy)
+For a message to be split, it looks for the parent message in the
+References or In-Reply-To header and then looks in the message id
+cache file (given by the variable `nnmail-message-id-cache-file') to
+see which group that message was put in. This group is returned.
+
+See the Info node `(gnus)Fancy Mail Splitting' for more details."
+ (let* ((refstr (or (message-fetch-field "references")
+ (message-fetch-field "in-reply-to")))
+ (references nil)
+ (res nil)
+ (regexp (if (consp nnmail-split-fancy-with-parent-ignore-groups)
+ (mapconcat
+ (lambda (x) (format "\\(%s\\)" x))
+ nnmail-split-fancy-with-parent-ignore-groups
+ "\\|")
+ nnmail-split-fancy-with-parent-ignore-groups)))
+ (when refstr
+ (setq references (nreverse (gnus-split-references refstr)))
+ (unless (gnus-buffer-live-p nnmail-cache-buffer)
+ (nnmail-cache-open))
+ (mapcar (lambda (x)
+ (setq res (or (nnmail-cache-fetch-group x) res))
+ (when (or (member res '("delayed" "drafts" "queue"))
+ (and regexp res (string-match regexp res)))
+ (setq res nil)))
+ references)
+ res)))