func TestRollbackOnContextCanceled(t *testing.T) {
	dsn := dockertest.RunTestPostgreSQL(t) // or simply load from the env

	db, err := sql.Open("pgx/v5", dsn)
	require.NoError(t, err)
	t.Cleanup(func() { _ = db.Close() })
	require.EventuallyWithT(t, func(collect *assert.CollectT) {
		assert.NoError(collect, db.PingContext(t.Context()))
	}, 10*time.Second, 100*time.Millisecond)

	ctx, cancel := context.WithCancel(t.Context())
	t.Cleanup(cancel)

	tx, err := db.BeginTx(ctx, nil)
	require.NoError(t, err)

	_, err = tx.ExecContext(ctx, "SELECT 1")
	require.NoError(t, err)

	cancel()
	time.Sleep(1 * time.Nanosecond) // give the database/sql auto-rollback some time to kick in

	// this races now with the database/sql auto-rollback on context cancellation
	// https://github.com/golang/go/blob/07840ceeed4afd10324a552e8c87a8ee363aa24a/src/database/sql/sql.go#L2211-L2226
	// depending on the outcome, we either get sql.ErrTxDone or "conn closed"
	require.NoError(t, tx.Rollback())
}