From 333885bfe7b8005c78746cb053e6b5054230fa92 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?G=C3=A9rald=20Barr=C3=A9?= <git@meziantou.net>
Date: Mon, 26 Feb 2024 00:06:04 -0500
Subject: [PATCH 1/2] Fix NullReferenceException in ChangeDeclarations

---
 src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs b/src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs
index 42ecbe4..5b4dee8 100644
--- a/src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs
+++ b/src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs
@@ -377,6 +377,9 @@ private void RemovePropertyByName(String propertyName)
 
         private void ChangeDeclarations(IEnumerable<ICssProperty> decls, Predicate<ICssProperty> defaultSkip, Func<ICssProperty, ICssProperty, Boolean> removeExisting)
         {
+            if (decls == null)
+                return;
+
             var declarations = new List<ICssProperty>();
 
             foreach (var newdecl in decls)

From b36924dbd11fd78595f3f0622bed557109540947 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?G=C3=A9rald=20Barr=C3=A9?=
 <meziantou@users.noreply.github.com>
Date: Mon, 26 Feb 2024 09:17:19 -0500
Subject: [PATCH 2/2] review

---
 src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs b/src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs
index 5b4dee8..11f937e 100644
--- a/src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs
+++ b/src/AngleSharp.Css/Dom/Internal/CssStyleDeclaration.cs
@@ -377,8 +377,10 @@ private void RemovePropertyByName(String propertyName)
 
         private void ChangeDeclarations(IEnumerable<ICssProperty> decls, Predicate<ICssProperty> defaultSkip, Func<ICssProperty, ICssProperty, Boolean> removeExisting)
         {
-            if (decls == null)
+            if (decls is null)
+            {
                 return;
+            }
 
             var declarations = new List<ICssProperty>();