Exception thrown when trying to deserialize a Feature, FeatureCollection, or Geometry with unrecognized properties during a partial read

[airbreather]

Fix incoming after I'm done with work for the day...

Repro

Found when deserializing objects from a chunked stream, but it's easy enough to reproduce with everything in-memory.

Program.cs

using System.Text;
using System.Text.Json;

using NetTopologySuite.Features;
using NetTopologySuite.Geometries;
using NetTopologySuite.IO.Converters;

JsonSerializerOptions options = new() { Converters = { new GeoJsonConverterFactory() } };

(Type NtsType, string Json)[] fails =
[
    (typeof(FeatureCollection[]), """
    { "type": "FeatureCollection", "_other": { } }
    """),

    (typeof(IFeature[]), """
    { "type": "Feature", "_other": { } }
    """),

    (typeof(Point[]), """
    { "type": "Point", "_other": { }, "coordinates": null }
    """),
];

for (int i = 0; i < fails.Length; i++)
{
    byte[] payload = Encoding.UTF8.GetBytes(fails[i].Json);
    using OneByOneStream s = new();
    s.WriteByte((byte)'[');
    s.Write(payload);
    for (int j = 0; j < 500; j++)
    {
        s.WriteByte((byte)',');
        s.Write(payload);
    }

    s.WriteByte((byte)']');
    s.Position = 0;
    try
    {
        _ = JsonSerializer.Deserialize(s, fails[i].NtsType, options);
        Console.Error.WriteLine("No error!");
    }
    catch (JsonException ex)
    {
        Console.Error.WriteLine($"{fails[i].Json}:");
        Console.Error.WriteLine($"{new string(' ', (int)ex.BytePositionInLine!.Value)}^");
        Console.Error.WriteLine($"    {ex.Message}");
        Console.Error.WriteLine($"    ->    {ex.InnerException?.Message}");
        Console.Error.WriteLine();
    }
}

internal sealed class OneByOneStream : MemoryStream
{
    public override int Read(Span<byte> buffer) => base.Read(buffer[..Math.Min(buffer.Length, 1)]);
    public override int Read(byte[] buffer, int offset, int count) => base.Read(buffer, offset, Math.Min(count, 1));
}

ConsoleApp0.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="NetTopologySuite.IO.GeoJSON4STJ" Version="4.0.0" />
  </ItemGroup>

</Project>

Sample output

{ "type": "FeatureCollection", "_other": { } }:
                                           ^
    The JSON value could not be converted to NetTopologySuite.Features.FeatureCollection. Path: $[0] | LineNumber: 0 | BytePositionInLine: 43.
    ->    Cannot skip tokens on partial JSON. Either get the whole payload and create a Utf8JsonReader instance where isFinalBlock is true or call TrySkip.

{ "type": "Feature", "_other": { } }:
                                 ^
    The JSON value could not be converted to NetTopologySuite.Features.IFeature. Path: $[0] | LineNumber: 0 | BytePositionInLine: 33.
    ->    Cannot skip tokens on partial JSON. Either get the whole payload and create a Utf8JsonReader instance where isFinalBlock is true or call TrySkip.

{ "type": "Point", "_other": { }, "coordinates": null }:
                               ^
    The JSON value could not be converted to NetTopologySuite.Geometries.Point. Path: $[0] | LineNumber: 0 | BytePositionInLine: 31.
    ->    Cannot skip tokens on partial JSON. Either get the whole payload and create a Utf8JsonReader instance where isFinalBlock is true or call TrySkip.

[espenrl]

Perhaps these are relevant

• In JsonConverter, .Skip() throws, but .TrySkip() never returns false during DeserializeAsync dotnet/runtime#39795
• Custom converters don't have to handle partial data dotnet/docs#19654
• https://github.com/dotnet/docs/pull/21991/files