eShopOnWeb/tests/FunctionalTests/Web/WebTestFixture.cs

using System;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc.Testing;
using Microsoft.EntityFrameworkCore;
using Microsoft.eShopWeb.Infrastructure.Data;
using Microsoft.eShopWeb.Infrastructure.Identity;
using Microsoft.eShopWeb.Web.Interfaces;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;

namespace Microsoft.eShopWeb.FunctionalTests.Web;

public class TestApplication : WebApplicationFactory<IBasketViewModelService>
{
    private readonly string _environment = "Development";

    protected override IHost CreateHost(IHostBuilder builder)
    {
        builder.UseEnvironment(_environment);

        // Add mock/test services to the builder here
        builder.ConfigureServices(services =>
        {
            var descriptors = services.Where(d =>
                                                d.ServiceType == typeof(DbContextOptions<CatalogContext>) ||
                                                d.ServiceType == typeof(DbContextOptions<AppIdentityDbContext>))
                                            .ToList();

            foreach (var descriptor in descriptors)
            {
                services.Remove(descriptor);
            }

            services.AddScoped(sp =>
            {
                // Replace SQLite with in-memory database for tests
                return new DbContextOptionsBuilder<CatalogContext>()
                .UseInMemoryDatabase("InMemoryDbForTesting")
                .UseApplicationServiceProvider(sp)
                .Options;
            });
            services.AddScoped(sp =>
            {
                // Replace SQLite with in-memory database for tests
                return new DbContextOptionsBuilder<AppIdentityDbContext>()
                .UseInMemoryDatabase("Identity")
                .UseApplicationServiceProvider(sp)
                .Options;
            });
        });

        return base.CreateHost(builder);
    }
}