using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Runtime.Serialization.Formatters;

using System.IO;

using System.Data;

using System.ComponentModel.DataAnnotations;

using System.Globalization;

using System.Reflection;

using System.Collections.ObjectModel;

​

using System.Text.Json;

using System.Text.Json.Serialization;

using System.Text.Json.Serialization.Metadata;

using System.Text.Json.Nodes;

​

using NUnit.Framework; // Throws NUnit.Framework.AssertionException

​

//https://stackoverflow.com/questions/78759504/do-not-serialize-empty-collections-and-handle-accordingly-in-deserialization?noredirect=1

​

using Json.Path;

​

#nullable enable

​

    class TestClass

    {

        public static void Test()

        {

            TestSingle();

            Console.WriteLine();

            TestMultiple();

​

            Console.WriteLine("All tests passed");

        }   

        static void TestSingle()

        {

            var jsonArray = JsonSerializer.SerializeToNode(new int[] { 1, 2, 3, 4} )!.AsArray();

​

            var path = JsonPath.Parse("$[0:-1]");

            var results = path.Evaluate(jsonArray);

​

            var newArray = JsonSerializer.SerializeToNode(results.Matches.Select(m => m.Value))!.AsArray(); // [1,2,3]

​

            Assert.That(new int [] { 1, 2, 3 }.SequenceEqual(newArray.Deserialize<int []>()!)); // PASSES

            Assert.That(newArray.Count == Math.Max(0, jsonArray.Count - 1)); // PASSES

​

            Console.WriteLine("Original array: {0}", JsonSerializer.Serialize(jsonArray, new JsonSerializerOptions { WriteIndented = false }));

            Console.WriteLine("Filtered array: {0}\n", JsonSerializer.Serialize(newArray));

        }

​

        static void TestMultiple()

        {

            var max = 100;

            for (var i = 0; i < max; i++)

            {

                var jsonArray = JsonSerializer.SerializeToNode(Enumerable.Range(1, i))!.AsArray();

                var path = JsonPath.Parse("$[0:-1]");

                var results = path.Evaluate(jsonArray);

​

                var newArray = JsonSerializer.SerializeToNode(results.Matches.Select(m => m.Value))!.AsArray();

​

                Assert.That(Enumerable.Range(1, Math.Max(0, i-1)).SequenceEqual(newArray.Deserialize<int []>()!)); // PASSES

                Assert.That(newArray.Count == Math.Max(0, jsonArray.Count - 1)); // PASSES

                if (i < 6)

                {

                    Console.WriteLine("Original array: {0}", JsonSerializer.Serialize(jsonArray, new JsonSerializerOptions { WriteIndented = false }));

                    Console.WriteLine("Filtered array: {0}\n", JsonSerializer.Serialize(newArray));

                }

            }

        }

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: {0} ({1}), {2}", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , Environment.Version, Environment.OSVersion);

            Console.WriteLine("System.Text.Json version: " + typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​