178             ca = c.ancestor(c2)

   178             ca = c.ancestor(c2)

   179             if not ca: # unrelated?

   179             if not ca: # unrelated?

   180                 continue

   180                 continue

   181             # named changed on only one side?

   181             # named changed on only one side?

   182             if ca.path() == c.path() or ca.path() == c2.path():

   182             if ca.path() == c.path() or ca.path() == c2.path():

   184                     continue

   184                     continue

   185                 copy[c.path()] = of

   185                 copy[c.path()] = of

   186 

   186 

   187     if not repo.ui.configbool("merge", "followcopies", True):

   187     if not repo.ui.configbool("merge", "followcopies", True):

   188         return {}, {}

   188         return {}, {}

   278 

   278 

   279     return copy, diverge

   279     return copy, diverge

   280 

   280 

   281 def symmetricdifference(repo, rev1, rev2):

   281 def symmetricdifference(repo, rev1, rev2):

   282     """symmetric difference of the sets of ancestors of rev1 and rev2

   282     """symmetric difference of the sets of ancestors of rev1 and rev2

   284     I.e. revisions that are ancestors of rev1 or rev2, but not both.

   284     I.e. revisions that are ancestors of rev1 or rev2, but not both.

   285     """

   285     """

   286     # basic idea:

   286     # basic idea:

   287     # - mark rev1 and rev2 with different colors

   287     # - mark rev1 and rev2 with different colors

   288     # - walk the graph in topological order with the help of a heap;

   288     # - walk the graph in topological order with the help of a heap;