From 1769c68234b3544230dc5e2fc38f75eb42b54d94 Mon Sep 17 00:00:00 2001
From: Gunnsteinn Hall <ghall@GHFoxy-Mac-mini.local>
Date: Fri, 21 Jul 2017 14:18:35 +0000
Subject: [PATCH] Add type check for Size in trailer.  Fixes #77

---
 pdf/core/parser.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pdf/core/parser.go b/pdf/core/parser.go
index 777328c6..baa14921 100644
--- a/pdf/core/parser.go
+++ b/pdf/core/parser.go
@@ -804,8 +804,8 @@ func (this *PdfParser) parseXrefStream(xstm *PdfObjectInteger) (*PdfObjectDictio
 
 	trailerDict := xs.PdfObjectDictionary
 
-	sizeObj := xs.PdfObjectDictionary.Get("Size").(*PdfObjectInteger)
-	if sizeObj == nil {
+	sizeObj, ok := xs.PdfObjectDictionary.Get("Size").(*PdfObjectInteger)
+	if !ok {
 		common.Log.Debug("ERROR: Missing size from xref stm")
 		return nil, errors.New("Missing Size from xref stm")
 	}