RightJoin / AutoRefresh

RightJoinWithDeferredLoadFixture.cs

using System;
using System.Reactive;
using System.Reactive.Concurrency;
using System.Collections.Generic;
using DynamicData.Binding;
using DynamicData.Kernel;
using FluentAssertions;
using Microsoft.Reactive.Testing;
using Xunit;

namespace DynamicData.Tests.Cache
{
    public record ProjectModel(Guid Id, string Title, Guid OwnerId);
    public record UserModel(Guid Id, string Name);

    public class RightJoinWithDeferredLoadFixture
    {
       
        private readonly SourceCache<ProjectModel, Guid> _projectsCache = new(static x => x.Id);
        private readonly SourceCache<UserModel, Guid> _usersCache = new(static x => x.Id);
        
        private readonly ObservableCollectionExtended<ProjectViewModel> _projects = new();
        private readonly ObservableCollectionExtended<ProjectViewModel> _selectedProjects = new();
        private readonly TestScheduler _scheduler = new();
        public RightJoinWithDeferredLoadFixture()
        {
            var shared = _usersCache.Connect()
                .RightJoin(
                    _projectsCache.Connect(),
                    static project => project.OwnerId,
                    static (user, project) => new ProjectViewModel(project, user))
                .RefCount();

            _ = shared
                .Bind(_projects)
                .Subscribe();

            _ = shared
                .AutoRefresh(static x => x.IsSelected, TimeSpan.FromMilliseconds(10), scheduler: _scheduler)
                .Filter(static x => x.IsEnabled && x.IsSelected)
                .Bind(_selectedProjects)
                .Subscribe();
        }

        [Fact]
        public void ThisWillNotFail()
        {
            _scheduler.Schedule(TimeSpan.FromSeconds(10), () => _projectsCache.AddOrUpdate(Api.Projects));
            _scheduler.Schedule(TimeSpan.FromSeconds(2), () => _usersCache.AddOrUpdate(Api.Users));
            
            _scheduler.AdvanceBy(TimeSpan.FromSeconds(2).Ticks);
            _scheduler.AdvanceBy(TimeSpan.FromSeconds(8).Ticks);

            _projects[0].IsSelected = true;
            _projects[2].IsSelected = true;
            _projects[3].IsSelected = true;

            _scheduler.AdvanceBy(TimeSpan.FromMilliseconds(10).Ticks);
            _selectedProjects.Count.Should().Be(3);

            _projects[2].IsSelected = false;
            _scheduler.AdvanceBy(TimeSpan.FromMilliseconds(10).Ticks);
            _selectedProjects.Count.Should().Be(2);

        }
    }

    public class ProjectViewModel : AbstractNotifyPropertyChanged
    {
        private bool _isSelected;
        public bool IsSelected
        {
            get => _isSelected;
            set => SetAndRaise(ref _isSelected, value);
        }

        public bool IsEnabled { get; set; } = true;

        public ProjectModel Model { get; }

        public Guid Id { get; set; } = Guid.Empty;

        public string Title { get; set; } = string.Empty;

        public Guid OwnerId { get; set; } = Guid.Empty;


        public string Username { get; set; } = string.Empty;

        public ProjectViewModel()
        {
            Model = new(Guid.Empty, string.Empty, Guid.Empty);
        }

        public ProjectViewModel(ProjectModel model, Optional<UserModel> optionalUser = default)
        {
            model = model ?? throw new ArgumentNullException(nameof(model));

            Model = model;

            Id = model.Id;
            Title = model.Title ?? string.Empty;
            OwnerId = model.OwnerId;

            Username = optionalUser.ValueOrDefault()?.Name ?? string.Empty;
        }


    }

    public static class Api
    {
        public static IReadOnlyCollection<ProjectModel> Projects { get; } = new[]
        {
            new ProjectModel(Guid.NewGuid(), "Project1", new Guid("243578cd-0739-4ddd-81d9-f43fccece753")),
            new ProjectModel(Guid.NewGuid(), "Project2", new Guid("243578cd-0739-4ddd-81d9-f43fccece753")),
            new ProjectModel(Guid.NewGuid(), "Project3", new Guid("243578cd-0739-4ddd-81d9-f43fccece753")),
            new ProjectModel(Guid.NewGuid(), "Project4", new Guid("243578cd-0739-4ddd-81d9-f43fccece753")),
            new ProjectModel(Guid.NewGuid(), "Project5", new Guid("3faef27b-7e0e-49a2-aa6c-29532411dc70")),
            new ProjectModel(Guid.NewGuid(), "Project6", new Guid("3faef27b-7e0e-49a2-aa6c-29532411dc70")),
            new ProjectModel(Guid.NewGuid(), "Project7", new Guid("3faef27b-7e0e-49a2-aa6c-29532411dc70")),
            new ProjectModel(Guid.NewGuid(), "Project8", new Guid("3faef27b-7e0e-49a2-aa6c-29532411dc70")),
        };

        public static IReadOnlyCollection<UserModel> Users { get; } = new[]
        {
            new UserModel(new Guid("243578cd-0739-4ddd-81d9-f43fccece753"), "User1"),
            new UserModel(new Guid("3faef27b-7e0e-49a2-aa6c-29532411dc70"), "User2"),
        };
    }
}