Best way to Inject SeedData into Custom WebApplicationFactory

This is where I was going with this:

Ammended factory:

public class GenericWebApplicationFactory<TStartup, TContext, TSeed>
    : WebApplicationFactory<TStartup>
    where TStartup : class
    where TContext : DbContext
    where TSeed : class, ISeedDataClass
{
    protected override void ConfigureWebHost(IWebHostBuilder builder)
    {
        base.ConfigureWebHost(builder);
        builder.UseEnvironment("Development");
        builder.ConfigureServices(services =>
        {
            var serviceProvider = new ServiceCollection()
                .AddEntityFrameworkInMemoryDatabase()
                .BuildServiceProvider();

            services.AddSingleton<ISeedDataClass,TSeed >();

            services.AddDbContextPool<TContext>(options =>
            {
                options.UseInMemoryDatabase("InMemoryDbForTesting");
                options.UseInternalServiceProvider(serviceProvider);
                options.EnableSensitiveDataLogging();
            });

            var sp = services.BuildServiceProvider();
            using (var scope = sp.CreateScope())
            {
                var scopedServices = scope.ServiceProvider;
                var db = scopedServices.GetRequiredService<TContext>();
                var logger = scopedServices.GetRequiredService<ILogger<GenericWebApplicationFactory<TStartup, TContext, TSeed>>>();

                var seeder = scopedServices.GetRequiredService<ISeedDataClass>();

                db.Database.EnsureCreated();

                try
                {
                    seeder.InitializeDbForTests();
                }
                catch (Exception ex)
                {
                    logger.LogError(ex, $"An error occurred seeding the database with test messages. Error: {ex.Message}");
                }
            }
        });
    }
}

Ammended usage:

    _client = new GenericWebApplicationFactory<Startup, GatewayContext, SeedDataClass>().CreateClient();

With example seed class:

public interface ISeedDataClass
{
    void InitializeDbForTests();
}

public class SeedDataClass : ISeedDataClass
{
    private readonly GatewayContext _db;

    public SeedDataClass(GatewayContext db)
    {
        _db = db;
    }

    public void InitializeDbForTests()
    {
        _db.Users.AddRange(
            // add some users here
        );

        _db.SaveChanges(true);
    }
}

Now, I can seed the in memory database however I see fit, per project where it is employed and my GenericWebApplicationFactory can now be pushed into a helper lib/nuget package which be re-used in other projects.