That is not true.
Since 1802 until 1966, the law only allowed the inscription of names from some of the usual saints' lists plus some very well known historical names:
"... les noms en usage dans les différents calendriers, et ceux des personnages connus dans l'histoire ancienne pourront seuls être reçus, comme prénoms, sur les registres de l’état civil destinés à constater la naissance des enfants; et il est interdit aux officiers publics d'en admettre aucun autre dans leurs actes."
Most of the accepted names were publied every year in the post calendar (just like a lot of Spanish calendars publish the saint or the saints of the day).
In 1966 regional names (that is, Occitan, Catalan, Breton, Basque, Alsatian, Corse... names), compound names and mythological names were allowed and some nicknames and variants. But there were not a
list of preapproved names.
In 1981 the law was changed (and remarked that there was not any list of preapproved names) and any name was allowed if it appeared in some calender or list and it was not ridicule.
Finally, since 1993, any name (even made up) is allowed. If the name is ridicule (the name itself or in combination with the surname or the surnames), the judge can ban the name.
But the existence of a preapproved name list is a myth because of a misunderstanding of the historical facts and it has been reported (also wrongly) for Spain, Germany and Italy.