+ (let ((tag-list (notmuch-tag-completions search-terms)))
+ (completing-read prompt tag-list nil nil nil 'notmuch-select-tag-history)))
+
+(defun notmuch-read-tag-changes (&optional initial-input &rest search-terms)
+ (let* ((all-tag-list (notmuch-tag-completions))
+ (add-tag-list (mapcar (apply-partially 'concat "+") all-tag-list))
+ (remove-tag-list (mapcar (apply-partially 'concat "-")
+ (if (null search-terms)
+ all-tag-list
+ (notmuch-tag-completions search-terms))))
+ (tag-list (append add-tag-list remove-tag-list))
+ (crm-separator " ")
+ ;; By default, space is bound to "complete word" function.
+ ;; Re-bind it to insert a space instead. Note that <tab>
+ ;; still does the completion.
+ (crm-local-completion-map
+ (let ((map (make-sparse-keymap)))
+ (set-keymap-parent map crm-local-completion-map)
+ (define-key map " " 'self-insert-command)
+ map)))
+ (delete "" (completing-read-multiple "Tags (+add -drop): "
+ tag-list nil nil initial-input
+ 'notmuch-read-tag-changes-history))))
+
+(defun notmuch-update-tags (tags tag-changes)
+ "Return a copy of TAGS with additions and removals from TAG-CHANGES.
+
+TAG-CHANGES must be a list of tags names, each prefixed with
+either a \"+\" to indicate the tag should be added to TAGS if not
+present or a \"-\" to indicate that the tag should be removed
+from TAGS if present."
+ (let ((result-tags (copy-sequence tags)))
+ (dolist (tag-change tag-changes)
+ (let ((op (string-to-char tag-change))
+ (tag (unless (string= tag-change "") (substring tag-change 1))))
+ (case op
+ (?+ (unless (member tag result-tags)
+ (push tag result-tags)))
+ (?- (setq result-tags (delete tag result-tags)))
+ (otherwise
+ (error "Changed tag must be of the form `+this_tag' or `-that_tag'")))))
+ (sort result-tags 'string<)))