From 2c927b1ca5ae8991bfc21b8a8d852f07f060ef20 Mon Sep 17 00:00:00 2001
From: Max Kalyabin <maksim@kalyabin.ru>
Date: Fri, 11 Dec 2020 01:10:01 +0300
Subject: [PATCH] fixes #1655 issue (#1656)

Resolve problem with incorrectly defined hyperlinks
---
 src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php b/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
index 9e6aeaf7..106fd44e 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
@@ -41,7 +41,7 @@ class Hyperlinks
         foreach (Coordinate::extractAllCellReferencesInRange($hyperlink['ref']) as $cellReference) {
             $cell = $worksheet->getCell($cellReference);
             if (isset($linkRel['id'])) {
-                $hyperlinkUrl = $this->hyperlinks[(string) $linkRel['id']];
+                $hyperlinkUrl = $this->hyperlinks[(string) $linkRel['id']] ?? null;
                 if (isset($hyperlink['location'])) {
                     $hyperlinkUrl .= '#' . (string) $hyperlink['location'];
                 }