Fix MethodFinder.cs

Author: StefH

src/System.Linq.Dynamic.Core/Parser/SupportedMethods/MethodFinder.cs

@@ -104,9 +104,17 @@ public int FindBestMethodBasedOnArguments(IEnumerable<MethodBase> methods, ref E
 
             if (applicable.Length == 1)
             {
-                MethodData md = applicable[0];
-                method = ((MethodInfo)md.MethodBase).GetBaseDefinition();
-                args = md.Args;
+                var methodData = applicable[0];
+                if (methodData.MethodBase is MethodInfo methodInfo)
+                {
+                    method = methodInfo.GetBaseDefinition();
+                }
+                else
+                {
+                    method = methodData.MethodBase;
+                }
+
+                args = methodData.Args;
             }
             else
             {

test/System.Linq.Dynamic.Core.Tests/System.Linq.Dynamic.Core.Tests.csproj

@@ -5,6 +5,7 @@
         <AssemblyName>System.Linq.Dynamic.Core.Tests</AssemblyName>
         <DebugType>full</DebugType>
         <SignAssembly>True</SignAssembly>
+        <LangVersion>10</LangVersion>
         <AssemblyOriginatorKeyFile>../../src/System.Linq.Dynamic.Core/System.Linq.Dynamic.Core.snk</AssemblyOriginatorKeyFile>
         <ProjectGuid>{912FBF24-3CAE-4A50-B5EA-E525B9FAEC80}</ProjectGuid>
     </PropertyGroup>