NameBuilder concurrency issue fix

Author: AlexUstinov

Orm/Xtensive.Orm/Orm/Providers/NameBuilder.cs

@@ -5,6 +5,7 @@
 // Created:    2007.08.27
 
 using System;
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
@@ -19,6 +20,7 @@
 using Xtensive.Orm.Weaving;
 using Xtensive.Reflection;
 using FieldInfo = Xtensive.Orm.Model.FieldInfo;
+using Module = System.Reflection.Module;
 using TypeInfo = Xtensive.Orm.Model.TypeInfo;
 
 namespace Xtensive.Orm.Providers
@@ -36,8 +38,11 @@ public sealed class NameBuilder
     private const string ReferenceForeignKeyFormat = "FK_{0}_{1}_{2}";
     private const string HierarchyForeignKeyFormat = "FK_{0}_{1}";
 
-    private readonly Dictionary<Pair<Type, string>, string> fieldNameCache = new Dictionary<Pair<Type, string>, string>();
-    private readonly object _lock = new object();
+    private readonly ConcurrentDictionary<PropertyInfo, string> fieldNameCache =
+      new ConcurrentDictionary<PropertyInfo, string>();
+    private static readonly Func<PropertyInfo, string> _fieldNameCacheValueFactory =
+      field => field.GetAttribute<OverrideFieldNameAttribute>()?.Name ?? field.Name;
+
     private readonly int maxIdentifierLength;
     private readonly NamingConvention namingConvention;
     private readonly bool isMultidatabase;
@@ -182,38 +187,14 @@ public string BuildFieldName(FieldDef field)
     }
 
     private string BuildFieldNameInternal(PropertyInfo propertyInfo)
-    {
-      var key = new Pair<Type, string>(propertyInfo.ReflectedType, propertyInfo.Name);
-
-      lock (fieldNameCache) {
-        string result;
-        if (fieldNameCache.TryGetValue(key, out result))
-          return result;
-        var attribute = propertyInfo.GetAttribute<OverrideFieldNameAttribute>();
-        if (attribute!=null) {
-          result = attribute.Name;
-          fieldNameCache.Add(key, result);
-          return result;
-        }
-      }
-
-      return propertyInfo.Name;
-    }
+      => fieldNameCache.GetOrAdd(propertyInfo, _fieldNameCacheValueFactory);
 
     /// <summary>
     /// Builds the name of the field.
     /// </summary>
     /// <param name="propertyInfo">The property info.</param>
     public string BuildFieldName(PropertyInfo propertyInfo)
-    {
-      lock (fieldNameCache) {
-        var key = new Pair<Type, string>(propertyInfo.ReflectedType, propertyInfo.Name);
-        string result;
-        return fieldNameCache.TryGetValue(key, out result)
-          ? result
-          : propertyInfo.Name;
-      }
-    }
+      => fieldNameCache.TryGetValue(propertyInfo, out string result) ? result : propertyInfo.Name;
 
     /// <summary>
     /// Builds the name of the explicitly implemented field.