The Chida ("Shem Hagedolim Hakhadash") states that Vidal Hatzarfati
"had a Yikhus till Rabbenu Tam, the son of the daughter of Rashi.
And I heard that the Rabbi Eliyahu was 15th generation >from Rabbeinu
Yet the Chida does not trace the intervening generations. Therefore
the statement in the Jewish Encyclopedia that the Chida "traced ...
to a line of French rabbis descended >from Rashi" is inaccurate. He
refers to a tradition without providing details of "a line."
Furthermore there were a number of families called Tsarfati, since
it indicated origins in France. The Treves family, descended from
Rashi also had members who used the appellative "Tsarfati." The
Trabot family was also known as Tsarfati, and although intermarried
with Treves, did not claim Rashi descent. See Yosef Grin's
"Mishpakhat Trabot". Grin disputes the claim that Treves and
Trabot were variant forms of the same name.
from the Chida's comment no doubt there are Tsarfati families whichhold a tradition of Rashi descent, but I would appreciate further
Petah Tikvah, Israel