(isearch-search): Refuse to match invisible text.

(isearch-range-invisible): New function.
(search-invisible): New user option.

1 files changed, 49 insertions, 12 deletions

diff --git a/lisp/isearch.el b/lisp/isearch.el
index 28fe63335d0..9e5ad7d4a2e 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -138,6 +138,10 @@ You might want to use something like \"[ \\t\\r\\n]+\" instead.")
 (defvar search-highlight nil
   "*Non-nil means incremental search highlights the current match.")
 
+(defvar search-invisible nil
+  "*Non-nil means incremental search can match text hidden by an overlay.
+\(This applies when using `noutline.el'.)")
+
 (defvar isearch-mode-hook nil
   "Function(s) to call after starting up an incremental search.")
 
@@ -1350,20 +1354,31 @@ If there is no completion possible, say so and continue searching."
             (isearch-no-upper-case-p isearch-string isearch-regexp)))
   (condition-case lossage
       (let ((inhibit-quit nil)
-            (case-fold-search isearch-case-fold-search))
+            (case-fold-search isearch-case-fold-search)
+            (retry t))
         (if isearch-regexp (setq isearch-invalid-regexp nil))
         (setq isearch-within-brackets nil)
-        (setq isearch-success
-              (funcall
-               (cond (isearch-word
-                      (if isearch-forward
-                          'word-search-forward 'word-search-backward))
-                     (isearch-regexp
-                      (if isearch-forward
-                          're-search-forward 're-search-backward))
-                     (t
-                      (if isearch-forward 'search-forward 'search-backward)))
-               isearch-string nil t))
+        (while retry
+          (setq isearch-success
+                (funcall
+                 (cond (isearch-word
+                        (if isearch-forward
+                            'word-search-forward 'word-search-backward))
+                       (isearch-regexp
+                        (if isearch-forward
+                            're-search-forward 're-search-backward))
+                       (t
+                        (if isearch-forward 'search-forward 'search-backward)))
+                 isearch-string nil t))
+          ;; Clear RETRY unless we matched some invisible text
+          ;; and we aren't supposed to do that.
+          (if (or search-invisible
+                  (not isearch-success)
+                  (bobp) (eobp)
+                  (= (match-beginning 0) (match-end 0))
+                  (not (isearch-range-invisible
+                        (match-beginning 0) (match-end 0))))
+              (setq retry nil)))
         (setq isearch-just-started nil)
         (if isearch-success
             (setq isearch-other-end
@@ -1391,6 +1406,28 @@ If there is no completion possible, say so and continue searching."
          (ding))
     (goto-char (nth 2 (car isearch-cmds)))))
 
+(defun isearch-range-invisible (beg end)
+  "Return t if all the bext from BEG to END is invisible."
+  (and (/= beg end)
+       ;; Check that invisibility runs up to END.
+       (save-excursion
+         (goto-char beg)
+         ;; 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)
+                     (let ((prop
+                            (get-char-property (point) 'invisible)))
+                       (if (eq buffer-invisibility-spec t)
+                           prop
+                         (or (memq prop buffer-invisibility-spec)
+                             (assq prop buffer-invisibility-spec)))))
+           (if (get-text-property (point) 'invisible)
+               (goto-char (next-single-property-change (point) 'invisible
+                                                       nil end))
+             (goto-char (next-overlay-change (point)))))
+         ;; See if invisibility reaches up thru END.
+         (>= (point) end))))
 
 
 ;;; Highlighting