Testing

Tests can run against a real database, or against SQLite, which needs no server.

SQLite in a temporary file

Use a SQLite database in the test temporary directory: each test gets its own, deleted after the test.

func TestUserRepository(t *testing.T) {
  t.Parallel()

  var (
    repository *UserRepository
    spans      *tracetest.InMemoryExporter
  )

  coretest.Start(t,
    core.New(sql.Module, sql.AsMigrations(migrations.FS), fx.Provide(NewUserRepository)),
    config.AsOptions(config.WithValues(map[string]any{
      "sql.driver": "sqlite",
      "sql.dsn":    filepath.Join(t.TempDir(), "test.db"),
    })),
    sql.Migrate(),
    fx.Populate(&repository, &spans),
  )

  user, err := repository.Create(t.Context(), "test_user")
  require.NoError(t, err)

  spantest.HasSpan(t, spans, spantest.WithName("INSERT"))
}

• sql.Migrate() applies the migrations before the test runs, like in production.
• Prefer a file over :memory:: an in-memory SQLite database exists per connection, and the pool opens several.
• SQL must then work with both databases: placeholders (? works in SQLite and MySQL, $1 in SQLite and PostgreSQL) and types differ. When they do not, test against the real database.

A real database

Set sql.driver and sql.dsn to a database started for the tests, for example with Testcontainers or a CI service, and skip the tests when it is not available:

dsn := os.Getenv("TEST_POSTGRES_DSN")
if dsn == "" {
  t.Skip("TEST_POSTGRES_DSN is not set")
}