I am using CustomWebApplicationFactory to overide DbContextFactory to use an SQLite DB in integration test –

public class CustomWebApplicationFactory<TStartup> 
: WebApplicationFactory<TStartup> where TStartup : class
{
protected override void ConfigureWebHost(IWebHostBuilder builder)
{
    builder.ConfigureServices(services =>
    {
        // Remove the app's ApplicationDbContext registration.
        removeService(services, typeof(DbContextOptions<PimsDbContext>));
        removeService(services, typeof(IDbContextFactory<PimsDbContext>));

        // Use in-memory SQLite database for testing.
        // Create single connection for all DbContext instances, as a new SQLite in-memory database is created for each connection.
        services.AddSingleton<DbConnection>(container =>
        {
            var connection = new SqliteConnection("DataSource=:memory:");
            connection.Open();
            Console.WriteLine($"Connection address dbcontextfactory: {connection.GetHashCode()}");
            return connection;
        });

        // Override DB context in Program.cs with SQLite in-memory database
        services.AddDbContextFactory<PimsDbContext>((container, options) =>
        {
            var connection = container.GetRequiredService<DbConnection>();
            options.UseSqlite(connection);
        }, ServiceLifetime.Singleton);

        services.AddScoped(typeof(IGenericRepository<>), typeof(GenericRepository<>));
        // Build the service provider.
        var sp = services.BuildServiceProvider();

        var dbContextFactory = sp.GetRequiredService<IDbContextFactory<PimsDbContext>>();
        var db = dbContextFactory.CreateDbContext();

        // Ensure the database is created.
        db.Database.EnsureCreated();

        SeedData(db);
    });
}

But when I run the test, I observed that application is using a different instance of DbContextFactory than the one injected in ConfigureServices, due to which the seeded data is not present in that Dbcontext while running the test.

Test –

public class ControllerIntegrationTest
{
    private CustomWebApplicationFactory<Program> _factory;
    private HttpClient _client;
    
    [SetUp]
    public void SetUp()
    {
        _factory = new CustomWebApplicationFactory<Program>();
        _client = _factory.CreateClient();
    }

    //... Test methods calling controller endpoint

}

Any idea why application is not using the same singleton DbContextFactory?