System.Linq.Expressions.Expression.ValidateOpAssignConversionLambda C# (CSharp) Method

        private static void ValidateOpAssignConversionLambda(LambdaExpression conversion, Expression left, MethodInfo method, ExpressionType nodeType)
        {
            Type delegateType = conversion.Type;
            Debug.Assert(typeof(System.MulticastDelegate).IsAssignableFrom(delegateType) && delegateType != typeof(System.MulticastDelegate));
            MethodInfo mi = delegateType.GetMethod("Invoke");
            ParameterInfo[] pms = mi.GetParametersCached();
            Debug.Assert(pms.Length == conversion.ParameterCount);
            if (pms.Length != 1)
            {
                throw Error.IncorrectNumberOfMethodCallArguments(conversion, nameof(conversion));
            }
            if (!TypeUtils.AreEquivalent(mi.ReturnType, left.Type))
            {
                throw Error.OperandTypesDoNotMatchParameters(nodeType, conversion.ToString());
            }
            if (method != null)
            {
                // The parameter type of conversion lambda must be the same as the return type of the overload method
                if (!TypeUtils.AreEquivalent(pms[0].ParameterType, method.ReturnType))
                {
                    throw Error.OverloadOperatorTypeDoesNotMatchConversionType(nodeType, conversion.ToString());
                }
            }
        }