From bcf619955b11d84c18d759e77299640fcfcce06d Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 30 Oct 2014 09:27:48 +0530
Subject: [PATCH] E-book viewer: Clear history when reloading the book, to
 avoid errors, since the locations pointed to by the history may no longer be
 valid anyway

---
 src/calibre/gui2/viewer/main.py | 1 +
 src/calibre/gui2/viewer/ui.py   | 7 ++++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/calibre/gui2/viewer/main.py b/src/calibre/gui2/viewer/main.py
index 31b7aef20f..cd19c2c28a 100644
--- a/src/calibre/gui2/viewer/main.py
+++ b/src/calibre/gui2/viewer/main.py
@@ -955,6 +955,7 @@ class EbookViewer(MainWindow):
                 reopen_at = self.current_page_bookmark
             except Exception:
                 reopen_at = None
+            self.history.clear()
             self.load_ebook(self.iterator.pathtoebook, reopen_at=reopen_at)
             return
 
diff --git a/src/calibre/gui2/viewer/ui.py b/src/calibre/gui2/viewer/ui.py
index 0066f25411..9683dd9f07 100644
--- a/src/calibre/gui2/viewer/ui.py
+++ b/src/calibre/gui2/viewer/ui.py
@@ -106,14 +106,15 @@ class History(list):  # {{{
         self.action_back = action_back
         self.action_forward = action_forward
         super(History, self).__init__(self)
+        self.clear()
+
+    def clear(self):
+        del self[:]
         self.insert_pos = 0
         self.back_pos = None
         self.forward_pos = None
         self.set_actions()
 
-    def clear(self):
-        del self[:]
-
     def set_actions(self):
         if self.action_back is not None:
             self.action_back.setDisabled(self.back_pos is None)