What is the legal test for bringing a defendant before a magistrate within 48 hours of their arrest?

In People v. Ross (1965) 236 Cal.App.2d 364, 367-368, 46 Cal.Rptr. 41, defendants were arrested in the early morning hours on a Friday and arraigned in the afternoon of Monday. The court held that "defendants were taken before a magistrate and arraigned on the afternoon of the next regular court session on the second legal business day following the day of their arrest. Excluding Saturday and Sunday, the 48-hour statutory minimum would have expired at 3:30 a.m. on Tuesday, May 12, 1964; thus, defendants were brought before a magistrate 'within two days after [their] arrest, excluding Sundays and holidays.' " Although the court used "48-hour" language, the defendants were arraigned well within the statutory time regardless of how the court explained its calculation. The additional comment of the court--that the time expired the next day--was unnecessary to the decision.