Workaround for Emacs bug #8721.

The emacs bug is that isearch cannot search through invisible text
when the 'invisible' property is a list.

The patch adds `notmuch-isearch-range-invisible' function which
is the same as `isearch-range-invisible' but with fixed Emacs bug
 #8721.  Advice added for `isearch-range-invisible' which calls
`notmuch-isearch-range-invisible' instead of the original
`isearch-range-invisible' when in `notmuch-show-mode'.

diff --git a/emacs/notmuch-wash.el b/emacs/notmuch-wash.el
index 6760f3e743c3a578dbba46758d682292a1a55784..cf5e9111e7f430fedecaf30a7d984d7bb4e11490 100644 (file)
--- a/emacs/notmuch-wash.el
+++ b/emacs/notmuch-wash.el
@@ -319,4 +319,71 @@ for error."
 
 ;;
 
+;; Temporary workaround for Emacs bug #8721
+;; http://debbugs.gnu.org/cgi/bugreport.cgi?bug=8721
+
+(defun notmuch-isearch-range-invisible (beg end)
+  "Same as `isearch-range-invisible' but with fixed Emacs bug #8721."
+  (when (/= beg end)
+    ;; Check that invisibility runs up to END.
+    (save-excursion
+      (goto-char beg)
+      (let (;; can-be-opened keeps track if we can open some overlays.
+           (can-be-opened (eq search-invisible 'open))
+           ;; the list of overlays that could be opened
+           (crt-overlays nil))
+       (when (and can-be-opened isearch-hide-immediately)
+         (isearch-close-unnecessary-overlays beg end))
+       ;; If the following character is currently invisible,
+       ;; skip all characters with that same `invisible' property value.
+       ;; Do that over and over.
+       (while (and (< (point) end) (invisible-p (point)))
+         (if (invisible-p (get-text-property (point) 'invisible))
+             (progn
+               (goto-char (next-single-property-change (point) 'invisible
+                                                       nil end))
+               ;; if text is hidden by an `invisible' text property
+               ;; we cannot open it at all.
+               (setq can-be-opened nil))
+           (when can-be-opened
+             (let ((overlays (overlays-at (point)))
+                   ov-list
+                   o
+                   invis-prop)
+               (while overlays
+                 (setq o (car overlays)
+                       invis-prop (overlay-get o 'invisible))
+                 (if (invisible-p invis-prop)
+                     (if (overlay-get o 'isearch-open-invisible)
+                         (setq ov-list (cons o ov-list))
+                       ;; We found one overlay that cannot be
+                       ;; opened, that means the whole chunk
+                       ;; cannot be opened.
+                       (setq can-be-opened nil)))
+                 (setq overlays (cdr overlays)))
+               (if can-be-opened
+                   ;; It makes sense to append to the open
+                   ;; overlays list only if we know that this is
+                   ;; t.
+                   (setq crt-overlays (append ov-list crt-overlays)))))
+           (goto-char (next-overlay-change (point)))))
+       ;; See if invisibility reaches up thru END.
+       (if (>= (point) end)
+           (if (and can-be-opened (consp crt-overlays))
+               (progn
+                 (setq isearch-opened-overlays
+                       (append isearch-opened-overlays crt-overlays))
+                 (mapc 'isearch-open-overlay-temporary crt-overlays)
+                 nil)
+             (setq isearch-hidden t)))))))
+
+(defadvice isearch-range-invisible (around notmuch-isearch-range-invisible-advice activate)
+  "Call `notmuch-isearch-range-invisible' instead of the original
+`isearch-range-invisible' when in `notmuch-show-mode' mode."
+  (if (eq major-mode 'notmuch-show-mode)
+      (setq ad-return-value (notmuch-isearch-range-invisible beg end))
+    ad-do-it))
+
+;;
+
 (provide 'notmuch-wash)