911         # use linkrev to find the first changeset where self appeared

   911         # use linkrev to find the first changeset where self appeared

   912         base = self

   912         base = self

   913         introrev = self.introrev()

   913         introrev = self.introrev()

   914         if self.rev() != introrev:

   914         if self.rev() != introrev:

   915             base = self.filectx(self.filenode(), changeid=introrev)

   915             base = self.filectx(self.filenode(), changeid=introrev)

   916 

   918 

   917         # This algorithm would prefer to be recursive, but Python is a

   919         # This algorithm would prefer to be recursive, but Python is a

   918         # bit recursion-hostile. Instead we do an iterative

   920         # bit recursion-hostile. Instead we do an iterative

   919         # depth-first search.

   921         # depth-first search.

   920 

   922