From c10085c99e08828d042ef46808a8d6953ba5bd3d Mon Sep 17 00:00:00 2001
From: Alexandre Saelens <alexandre.saelens@dna.co.nz>
Date: Tue, 23 Jan 2024 13:22:47 +1300
Subject: [PATCH] FIX: Make sureHtmlDiff::compareHTML is not passed null values

---
 src/VersionFeed.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/VersionFeed.php b/src/VersionFeed.php
index ad7e1bc..9c7fb2c 100644
--- a/src/VersionFeed.php
+++ b/src/VersionFeed.php
@@ -94,7 +94,7 @@ class VersionFeed extends SiteTreeExtension
             if (isset($previous)) {
                 // Produce the diff fields for use in the template.
                 if ($version->Title != $previous->Title) {
-                    $diffTitle = HtmlDiff::compareHTML($version->Title, $previous->Title);
+                    $diffTitle = HtmlDiff::compareHTML($version->Title ?? '', $previous->Title ?? '');
 
                     $version->DiffTitle = DBField::create_field('HTMLText', null);
                     $version->DiffTitle->setValue(
@@ -107,7 +107,7 @@ class VersionFeed extends SiteTreeExtension
                 }
 
                 if ($version->Content != $previous->Content) {
-                    $diffContent = HtmlDiff::compareHTML($version->Content, $previous->Content);
+                    $diffContent = HtmlDiff::compareHTML($version->Content ?? '', $previous->Content ?? '');
 
                     $version->DiffContent = DBField::create_field('HTMLText', null);
                     $version->DiffContent->setValue('<div>'.$diffContent.'</div>');