Optimize implicit operator lookup in ExpressionPromoter

Agent-Logs-Url: https://github.com/zzzprojects/System.Linq.Dynamic.Core/sessions/82ed2f4e-0c76-407c-a330-d4043e96162f

Co-authored-by: StefH <249938+StefH@users.noreply.github.com>

Author: Copilot

src/System.Linq.Dynamic.Core/Parser/ExpressionPromoter.cs

@@ -140,12 +140,20 @@ public ExpressionPromoter(ParsingConfig config)
         // Look for op_Implicit on the source type or the target type.
         var implicitOperator =
             returnType.GetMethods(BindingFlags.Public | BindingFlags.Static)
-                .Where(m => m.Name == "op_Implicit" && m.ReturnType == type)
-                .FirstOrDefault(m => m.GetParameters().FirstOrDefault()?.ParameterType == returnType)
+                .FirstOrDefault(m =>
+                {
+                    if (m.Name != "op_Implicit" || m.ReturnType != type) return false;
+                    var parameters = m.GetParameters();
+                    return parameters.Length == 1 && parameters[0].ParameterType == returnType;
+                })
             ??
             type.GetMethods(BindingFlags.Public | BindingFlags.Static)
-                .Where(m => m.Name == "op_Implicit" && m.ReturnType == type)
-                .FirstOrDefault(m => m.GetParameters().FirstOrDefault()?.ParameterType == returnType);
+                .FirstOrDefault(m =>
+                {
+                    if (m.Name != "op_Implicit" || m.ReturnType != type) return false;
+                    var parameters = m.GetParameters();
+                    return parameters.Length == 1 && parameters[0].ParameterType == returnType;
+                });
 
         if (implicitOperator != null)
         {

test/System.Linq.Dynamic.Core.Tests/DynamicExpressionParserTests.cs

@@ -1556,7 +1556,7 @@ public void DynamicExpressionParser_ParseLambda_With_Implicit_Operator_In_Method
         var expression = $"{nameof(MyMethodsWithImplicitOperatorSupport)}.{nameof(MyMethodsWithImplicitOperatorSupport.UsesMyStructWithImplicitOperator)}(\"Foo\")";
 
         // Act
-        var parser = new ExpressionParser([], expression, [], ParsingConfig.Default);
+        var parser = new ExpressionParser(parameters: [], expression, values: [], ParsingConfig.Default);
         var parsedExpression = parser.Parse(typeof(string));
         var lambda = Expression.Lambda<Func<string>>(parsedExpression);
         var method = lambda.Compile();