Small fixes

src/Serilog.Extensions.Logging/Extensions/Logging/LoggerProviderCollection.cs

@@ -26,7 +26,7 @@ namespace Serilog.Extensions.Logging
     /// </summary>
     public class LoggerProviderCollection : IDisposable
     {
-        volatile ILoggerProvider[] _providers = new ILoggerProvider[0];
+        volatile ILoggerProvider[] _providers = Array.Empty<ILoggerProvider>();
 
         /// <summary>
         /// Add <paramref name="provider"/> to the collection.
@@ -36,16 +36,16 @@ public void AddProvider(ILoggerProvider provider)
         {
             if (provider == null) throw new ArgumentNullException(nameof(provider));
 
-            var existing = _providers;
-            var added = existing.Concat(new[] {provider}).ToArray();
+            ILoggerProvider[] existing, added;
 
-#pragma warning disable 420 // ref to a volatile field
-            while (Interlocked.CompareExchange(ref _providers, added, existing) != existing)
-#pragma warning restore 420
+            do
             {
                 existing = _providers;
                 added = existing.Concat(new[] { provider }).ToArray();
             }
+#pragma warning disable 420 // ref to a volatile field
+            while (Interlocked.CompareExchange(ref _providers, added, existing) != existing);
+#pragma warning restore 420
         }
 
         /// <summary>

src/Serilog.Extensions.Logging/Extensions/Logging/SerilogLoggerProvider.cs

@@ -69,8 +69,7 @@ public void Enrich(LogEvent logEvent, ILogEventPropertyFactory propertyFactory)
             List<LogEventPropertyValue> scopeItems = null;
             for (var scope = CurrentScope; scope != null; scope = scope.Parent)
             {
-                LogEventPropertyValue scopeItem;
-                scope.EnrichAndCreateScopeItem(logEvent, propertyFactory, out scopeItem);
+                scope.EnrichAndCreateScopeItem(logEvent, propertyFactory, out LogEventPropertyValue scopeItem);
 
                 if (scopeItem != null)
                 {

src/Serilog.Extensions.Logging/Extensions/Logging/SerilogLoggerScope.cs

@@ -57,8 +57,7 @@ public void EnrichAndCreateScopeItem(LogEvent logEvent, ILogEventPropertyFactory
                 return;
             }
 
-            var stateProperties = _state as IEnumerable<KeyValuePair<string, object>>;
-            if (stateProperties != null)
+            if (_state is IEnumerable<KeyValuePair<string, object>> stateProperties)
             {
                 scopeItem = null; // Unless it's `FormattedLogValues`, these are treated as property bags rather than scope items.
 
@@ -78,7 +77,7 @@ public void EnrichAndCreateScopeItem(LogEvent logEvent, ILogEventPropertyFactory
                         key = key.Substring(1);
                         destructureObject = true;
                     }
-                    
+
                     var property = propertyFactory.CreateProperty(key, stateProperty.Value, destructureObject);
                     logEvent.AddPropertyIfAbsent(property);
                 }

src/Serilog.Extensions.Logging/SerilogLoggerFactoryExtensions.cs

@@ -20,7 +20,7 @@ public static class SerilogLoggerFactoryExtensions
         /// <param name="dispose">When true, dispose <paramref name="logger"/> when the framework disposes the provider. If the
         /// logger is not specified but <paramref name="dispose"/> is true, the <see cref="Log.CloseAndFlush()"/> method will be
         /// called on the static <see cref="Log"/> class instead.</param>
-        /// <returns>The logger factory.</returns>
+        /// <returns>Reference to the supplied <paramref name="factory"/>.</returns>
         public static ILoggerFactory AddSerilog(
             this ILoggerFactory factory,
             ILogger logger = null,

src/Serilog.Extensions.Logging/SerilogLoggingBuilderExtensions.cs

@@ -32,7 +32,7 @@ public static class SerilogLoggingBuilderExtensions
         /// <param name="dispose">When true, dispose <paramref name="logger"/> when the framework disposes the provider. If the
         /// logger is not specified but <paramref name="dispose"/> is true, the <see cref="Log.CloseAndFlush()"/> method will be
         /// called on the static <see cref="Log"/> class instead.</param>
-        /// <returns>The logger factory.</returns>
+        /// <returns>Reference to the supplied <paramref name="builder"/>.</returns>
         public static ILoggingBuilder AddSerilog(this ILoggingBuilder builder, ILogger logger = null, bool dispose = false)
         {
             if (builder == null) throw new ArgumentNullException(nameof(builder));