diff --git a/Sharp7.Rx.Tests/Sharp7.Rx.Tests.csproj b/Sharp7.Rx.Tests/Sharp7.Rx.Tests.csproj
index d1de65b..2c16b68 100644
--- a/Sharp7.Rx.Tests/Sharp7.Rx.Tests.csproj
+++ b/Sharp7.Rx.Tests/Sharp7.Rx.Tests.csproj
@@ -6,6 +6,12 @@
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
     <AnalysisLevel>latest-Recommended</AnalysisLevel>
+
+    <!--
+       CA1859: Change type of field 'xxx' from interface to type for performance reasons
+       CA1852: Type 'ReadFromBuffer' can be sealed
+    -->
+    <NoWarn>$(NoWarn);CA1859;CA1852</NoWarn>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/Sharp7.Rx.Tests/VariableNameParserTests.cs b/Sharp7.Rx.Tests/VariableNameParserTests.cs
index 4ecf1c5..c3e0405 100644
--- a/Sharp7.Rx.Tests/VariableNameParserTests.cs
+++ b/Sharp7.Rx.Tests/VariableNameParserTests.cs
@@ -42,7 +42,7 @@ internal class VariableNameParserTests
     public void Invalid(string? input)
     {
         var parser = new VariableNameParser();
-        Should.Throw<InvalidS7AddressException>(() => parser.Parse(input));
+        Should.Throw<InvalidS7AddressException>(() => parser.Parse(input!));
     }
 
     public static IEnumerable<TestCase> ValidTestCases()