From d6a874be9e8e3ad6d17869e64bd6c009c0376f9d Mon Sep 17 00:00:00 2001
From: Rolf Kristensen <snakefoot@users.noreply.github.com>
Date: Mon, 14 Nov 2022 20:11:56 +0100
Subject: [PATCH] NLogBeginScopeParser - CaptureScopeProperties with cached
 scopePropertyCount (#639)

---
 .../Logging/NLogBeginScopeParser.cs           | 63 +++++++++----------
 .../Logging/NLogLogger.cs                     |  1 -
 .../Logging/NLogMessageParameterList.cs       | 15 +++--
 3 files changed, 37 insertions(+), 42 deletions(-)

diff --git a/src/NLog.Extensions.Logging/Logging/NLogBeginScopeParser.cs b/src/NLog.Extensions.Logging/Logging/NLogBeginScopeParser.cs
index dea8500a..db2d72a7 100644
--- a/src/NLog.Extensions.Logging/Logging/NLogBeginScopeParser.cs
+++ b/src/NLog.Extensions.Logging/Logging/NLogBeginScopeParser.cs
@@ -52,17 +52,43 @@ private IDisposable CaptureScopeProperties(IReadOnlyList<KeyValuePair<string, ob
         {
             object scopeObject = scopePropertyList;
 
-            if (scopePropertyList.Count > 0)
+            var scopePropertyCount = scopePropertyList.Count;
+            if (scopePropertyCount > 0)
             {
-                if (NLogLogger.OriginalFormatPropertyName.Equals(scopePropertyList[scopePropertyList.Count - 1].Key))
+                if (NLogLogger.OriginalFormatPropertyName.Equals(scopePropertyList[scopePropertyCount - 1].Key))
                 {
-                    scopePropertyList = ExcludeOriginalFormatProperty(scopePropertyList);
+                    var firstProperty = scopePropertyList[0];
+                    if (scopePropertyCount == 2 && !string.IsNullOrEmpty(firstProperty.Key) && !NLogLogger.OriginalFormatPropertyName.Equals(firstProperty.Key))
+                    {
+                        scopePropertyList = new[] { firstProperty };
+                    }
+                    else if (scopePropertyCount <= 2)
+                    {
+                        scopePropertyList = Array.Empty<KeyValuePair<string, object>>();
+                    }
+                    else
+                    {
+                        var propertyList = new List<KeyValuePair<string, object>>(scopePropertyCount - 1);
+                        for (var i = 0; i < scopePropertyCount; ++i)
+                        {
+                            var property = scopePropertyList[i];
+                            if (string.IsNullOrEmpty(property.Key))
+                            {
+                                continue;
+                            }
+                            if (NLogLogger.OriginalFormatPropertyName.Equals(property.Key))
+                            {
+                                continue; // Handle BeginScope("Hello {World}", "Earth")
+                            }
+                            propertyList.Add(property);
+                        }
+                        scopePropertyList = propertyList;
+                    }
                 }
                 else
                 {
                     scopePropertyList = IncludeActivityIdsProperties(scopePropertyList);
                 }
-
             }
 
             return ScopeContext.PushNestedStateProperties(scopeObject, scopePropertyList);
@@ -138,35 +164,6 @@ IEnumerator IEnumerable.GetEnumerator()
         }
 #endif
 
-        private static IReadOnlyList<KeyValuePair<string, object>> ExcludeOriginalFormatProperty(IReadOnlyList<KeyValuePair<string, object>> scopePropertyList)
-        {
-            if (scopePropertyList.Count == 2 && !NLogLogger.OriginalFormatPropertyName.Equals(scopePropertyList[0].Key))
-            {
-                scopePropertyList = new[] { scopePropertyList[0] };
-            }
-            else if (scopePropertyList.Count <= 2)
-            {
-                scopePropertyList = Array.Empty<KeyValuePair<string, object>>();
-            }
-            else
-            {
-                var propertyList = new List<KeyValuePair<string, object>>(scopePropertyList.Count - 1);
-                for (var i = 0; i < scopePropertyList.Count; ++i)
-                {
-                    var property = scopePropertyList[i];
-                    if (i == scopePropertyList.Count - 1 && i > 0 && NLogLogger.OriginalFormatPropertyName.Equals(property.Key))
-                    {
-                        continue; // Handle BeginScope("Hello {World}", "Earth")
-                    }
-
-                    propertyList.Add(property);
-                }
-                scopePropertyList = propertyList;
-            }
-
-            return scopePropertyList;
-        }
-
         public static IDisposable CaptureScopeProperties(IEnumerable scopePropertyCollection, ExtractorDictionary stateExtractor)
         {
             List<KeyValuePair<string, object>> propertyList = null;
diff --git a/src/NLog.Extensions.Logging/Logging/NLogLogger.cs b/src/NLog.Extensions.Logging/Logging/NLogLogger.cs
index 70ba3424..9a3bf577 100644
--- a/src/NLog.Extensions.Logging/Logging/NLogLogger.cs
+++ b/src/NLog.Extensions.Logging/Logging/NLogLogger.cs
@@ -164,7 +164,6 @@ private static void CaptureLogEventInfoParameters(LogEventInfo logEvent, NLogMes
         }
 
         private static readonly object[] SingleItemArray = { null };
-        private static readonly IList<MessageTemplateParameter> EmptyParameterArray = Array.Empty<MessageTemplateParameter>();
 
         /// <summary>
         /// Are all parameters positional and correctly mapped?
diff --git a/src/NLog.Extensions.Logging/Logging/NLogMessageParameterList.cs b/src/NLog.Extensions.Logging/Logging/NLogMessageParameterList.cs
index 127c418b..eee5ce02 100644
--- a/src/NLog.Extensions.Logging/Logging/NLogMessageParameterList.cs
+++ b/src/NLog.Extensions.Logging/Logging/NLogMessageParameterList.cs
@@ -157,20 +157,20 @@ private static bool TryGetParameterName(IReadOnlyList<KeyValuePair<string, objec
         /// </summary>
         private static IReadOnlyList<KeyValuePair<string, object>> CreateValidParameterList(IReadOnlyList<KeyValuePair<string, object>> parameterList)
         {
-            var validParameterList = new List<KeyValuePair<string, object>>(parameterList.Count);
-            for (int i = 0; i < parameterList.Count; ++i)
+            var parameterCount = parameterList.Count;
+            var validParameterList = new List<KeyValuePair<string, object>>(parameterCount);
+
+            for (int i = 0; i < parameterCount; ++i)
             {
-                var paramPair = parameterList[i];
-                if (string.IsNullOrEmpty(paramPair.Key))
+                if (!TryGetParameterName(parameterList, i, out var parameterName))
                     continue;
 
-                if (NLogLogger.OriginalFormatPropertyName.Equals(paramPair.Key))
-                {
+                if (NLogLogger.OriginalFormatPropertyName.Equals(parameterName))
                     continue;
-                }
 
                 validParameterList.Add(parameterList[i]);
             }
+
             return validParameterList;
         }
 
@@ -201,7 +201,6 @@ private static CaptureType GetCaptureType(char firstChar)
                 return CaptureType.Normal;
         }
 
-
         public int Count => _parameterList.Count - (_originalMessageIndex.HasValue ? 1 : 0);
 
         public bool IsReadOnly => true;