Fixed race condition in GetTypeInfo method

It was observed that a new ConvertTypeInfo instance was created twice for two threads simultaneously, adding the same type name to the assembly, which caused an ArgumentException "Duplicate type name within an assembly". This is the normal pattern when using a ConcurrentDictionary.

To resolve this, it is ensured that the new instance (emitting that type) is only created once. A normal Dictionary and locks are used now.

Author: ygoe

DeepConvert/DeepConvert.cs

@@ -848,8 +848,7 @@ private static DateTime ConvertNumeric(double num, DateNumericKind numericKind,
 
 		#endregion Helper methods
 
-		private static readonly ConcurrentDictionary<Type, ConvertTypeInfo> typeInfos =
-			new ConcurrentDictionary<Type, ConvertTypeInfo>();
+		private static readonly Dictionary<Type, ConvertTypeInfo> typeInfos = new Dictionary<Type, ConvertTypeInfo>();
 
 		/// <summary>
 		/// Returns an object of the specified type whose properties have the values from equally
@@ -906,7 +905,15 @@ public static Dictionary<string, object> ConvertToDictionary(object obj)
 		/// <returns>The <see cref="ConvertTypeInfo"/> instance to access the type properties.</returns>
 		private static ConvertTypeInfo GetTypeInfo(Type type)
 		{
-			return typeInfos.GetOrAdd(type, t => new ConvertTypeInfo(t));
+			lock (typeInfos)
+			{
+				if (!typeInfos.TryGetValue(type, out var convertTypeInfo))
+				{
+					convertTypeInfo = new ConvertTypeInfo(type);
+					typeInfos.Add(type, convertTypeInfo);
+				}
+				return convertTypeInfo;
+			}
 		}
 	}
 }

DeepConvert/DeepConvert.csproj

@@ -4,7 +4,7 @@
 		<TargetFrameworks>netstandard2.0;net45</TargetFrameworks>
 		<RootNamespace>Unclassified.Util</RootNamespace>
 		<AssemblyName>Unclassified.DeepConvert</AssemblyName>
-		<Version>1.4.0</Version>
+		<Version>1.4.1</Version>
 		<GenerateDocumentationFile>true</GenerateDocumentationFile>
 
 		<GeneratePackageOnBuild>true</GeneratePackageOnBuild>