The following shall have not only prospective but also retroactive effect:
(1) Article 315, whereby a descendant cannot be compelled, in a criminal case, to testify against his parents and ascendants;
(2) Articles 101 and 88, providing against collusion in cases of legal separation and annulment of marriage;
(3) Articles 283, 284, and 289, concerning the proof of illegitimate filiation;
(4) Article 838, authorizing the probate of a will on petition of the testator himself;
(5) Articles 1359 to 1369, relative to the reformation of instruments;
(6) Articles 476 to 481, regulating actions to quiet title;
(7) Articles 2029 to 2031, which are designed to promote compromises. (n)