From e8b21b2f290f83f7c20eed558d9dece0fef8b1de Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 9 Sep 2019 11:56:37 +0530
Subject: [PATCH] Avoid a rare error when calculating CFI

---
 src/pyj/read_book/cfi.pyj | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/pyj/read_book/cfi.pyj b/src/pyj/read_book/cfi.pyj
index 0fbc9c20ff..d913e78f5f 100644
--- a/src/pyj/read_book/cfi.pyj
+++ b/src/pyj/read_book/cfi.pyj
@@ -585,6 +585,8 @@ def at_point(ox, oy):  # {{{
     except Exception:
         cfi = None
 
+    if not p:
+        return None
 
     if cfi:
         if p.range is not None: