diff --git a/.gitignore b/.gitignore
index 4c12bd0b08..7e900c8f9e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 outputroot/
+.nuget/
 ## Ignore Visual Studio temporary files, build results, and
 ## files generated by popular Visual Studio add-ons.
 
diff --git a/test/Microsoft.TemplateEngine.Mocks/MockInstallerFactory.cs b/test/Microsoft.TemplateEngine.Mocks/MockInstallerFactory.cs
index 667f5d0856..c82ae1fd65 100644
--- a/test/Microsoft.TemplateEngine.Mocks/MockInstallerFactory.cs
+++ b/test/Microsoft.TemplateEngine.Mocks/MockInstallerFactory.cs
@@ -9,7 +9,7 @@ namespace Microsoft.TemplateEngine.Mocks
 {
     public class MockInstallerFactory : IInstallerFactory
     {
-        private Guid _factoryId = new Guid("00000000-0000-0000-0000-000000000000");
+        private readonly Guid _factoryId = new Guid("00000000-0000-0000-0000-000000000000");
 
         public string Name => "MockInstallerFactory";
 
diff --git a/test/Microsoft.TemplateEngine.TestHelper/XunitLoggerProvider.cs b/test/Microsoft.TemplateEngine.TestHelper/XunitLoggerProvider.cs
index b7a78be1a1..7513fa2014 100644
--- a/test/Microsoft.TemplateEngine.TestHelper/XunitLoggerProvider.cs
+++ b/test/Microsoft.TemplateEngine.TestHelper/XunitLoggerProvider.cs
@@ -78,7 +78,7 @@ public void Log<TState>(
 
                 var firstLinePrefix = $"| [{timestamp}] {_category} {logLevel}: ";
                 var lines = formatter(state, exception).Split(NewLineChars, StringSplitOptions.RemoveEmptyEntries);
-                messageBuilder.AppendLine(firstLinePrefix + lines.FirstOrDefault() ?? string.Empty);
+                messageBuilder.AppendLine(firstLinePrefix + (lines.FirstOrDefault() ?? string.Empty));
 
                 var additionalLinePrefix = "|" + new string(' ', firstLinePrefix.Length - 1);
                 foreach (var line in lines.Skip(1))