Fix bug #19157 with incorrect hscroll during I-search.

 lisp/isearch.el (isearch-update): Don't assume
 pos-visible-in-window-p will return nil when point is hscrolled
 out of view.

2 files changed, 16 insertions, 3 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index c3a01dac664..26376afe239 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2014-11-24  Eli Zaretskii  <eliz@gnu.org>
+
+        * isearch.el (isearch-update): Don't assume
+        pos-visible-in-window-p will return nil when point is hscrolled
+        out of view.  (Bug#19157)
+
 2014-11-20  Andrey Kotlarski  <m00naticus@gmail.com>
 
         * net/eww.el (eww-browse-url): Optionally create new eww buffer.
diff --git a/lisp/isearch.el b/lisp/isearch.el
index f0ce7050e78..c3e473a2ba6 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -974,10 +974,17 @@ The last thing it does is to run `isearch-update-post-hook'."
                 (other-window 1))
               (goto-char found-point))
           ;; Keep same hscrolling as at the start of the search when possible
-          (let ((current-scroll (window-hscroll)))
+          (let ((current-scroll (window-hscroll))
+                visible-p)
             (set-window-hscroll (selected-window) isearch-start-hscroll)
-            (unless (pos-visible-in-window-p)
-              (set-window-hscroll (selected-window) current-scroll))))
+            (setq visible-p (pos-visible-in-window-p nil nil t))
+            (if (or (not visible-p)
+                    ;; When point is not visible because of hscroll,
+                    ;; pos-visible-in-window-p returns non-nil, but
+                    ;; the X coordinate it returns is 1 pixel beyond
+                    ;; the last visible one.
+                    (>= (car visible-p) (window-body-width nil t)))
+                (set-window-hscroll (selected-window) current-scroll))))
         (if isearch-other-end
             (if (< isearch-other-end (point)) ; isearch-forward?
                 (isearch-highlight isearch-other-end (point))