[PATCH 1/5] emacs: hello: add helper functions for saved-searches

[Mark Walters]

Add helper functions to for saved searches to ease the transition to
the new plist form while maintaining backwards compatibility. They
will be used in the next patch.
---
 emacs/notmuch-hello.el |   39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/emacs/notmuch-hello.el b/emacs/notmuch-hello.el
index e325cd3..0b9ed16 100644
--- a/emacs/notmuch-hello.el
+++ b/emacs/notmuch-hello.el
@@ -269,6 +269,45 @@ (defun notmuch-hello-search (&optional search)
       (add-to-history 'notmuch-search-history search)))
   (notmuch-search search notmuch-search-oldest-first))
 
+(defun notmuch-saved-search-get (saved-search field)
+  "Get FIELD from SAVED-SEARCH.
+
+In the new style saved-search (a plist) this is just plist-get
+but, for backwards compatibility, this deals with the two
+old-style forms: cons cells (NAME . QUERY) and lists (NAME QUERY
+COUNT-QUERY)."
+  (cond
+   ((plist-get saved-search :name)
+    (plist-get saved-search field))
+   ;; It is not a plist so it is an old-style entry.
+   ((consp (cdr saved-search)) ;; It is a list (NAME QUERY COUNT-QUERY)
+    (case field
+      (:name (car saved-search))
+      (:query (second saved-search))
+      (:count-query (third saved-search))
+      (t nil)))
+   (t  ;; It is a cons-cell (NAME . QUERY)
+    (case field
+      (:name (car saved-search))
+      (:query (cdr saved-search))
+      (t nil)))))
+
+(defun notmuch-hello-saved-search-to-plist (saved-search)
+  "Convert a saved-search variable into plist form.
+
+The new style saved search is just a plist, but for backwards
+compatatibility we use this function to give them in
+plist-form. In all cases a new copy is returned so it is safe to
+modify the returned value."
+  (if (and (listp (cdr saved-search)) (plist-member saved-search :name))
+      (copy-seq saved-search)
+    (let ((fields (list :name :query :count-query))
+	  (plist-search))
+      (dolist (field fields plist-search)
+	(let ((string (notmuch-saved-search-get saved-search field)))
+	  (when string
+	    (setq plist-search (append plist-search (list field string)))))))))
+
 (defun notmuch-hello-add-saved-search (widget)
   (interactive)
   (let ((search (widget-value
-- 
1.7.10.4