From cefd8fc50f1285ab4be2bd869503282b2a9fa5ae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Samy=20Pess=C3=A9?= <samypesse@gmail.com>
Date: Thu, 27 Aug 2015 15:04:28 +0200
Subject: [PATCH] Don't fail if hook returns nothing for "page" and
 "page:before"

---
 lib/book.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/book.js b/lib/book.js
index 2e0ab5811..b306c51ad 100644
--- a/lib/book.js
+++ b/lib/book.js
@@ -512,7 +512,7 @@ Book.prototype.parsePage = function(filename, options) {
     var interpolate = function(fn) {
         return Q(fn(page))
         .then(function(_page) {
-            page = _page;
+            page = _page || page;
         });
     };