diff mercurial/copies.py @ 44162:baf3fe2977cc

copies: move early return in mergecopies() earlier

It wasn't obvious that the early return happened only when there are
no copies. That is the case, however, because if `fullcopy` is empty,
then so is `copies1` and `copies2`, and then so is `inversecopies1`
and `inversecopies2`, and then so is `allsources`, and then so is
`copy`, `diverge` and `renamedelete`.

By moving the early return earlier, we also avoid calculating the set
of added files from the base to each side.

Differential Revision: https://phab.mercurial-scm.org/D7975

--- a/mercurial/copies.py	Fri Jan 24 07:00:45 2020 -0800
+++ b/mercurial/copies.py	Wed Jan 22 15:20:12 2020 -0800
@@ -563,6 +563,9 @@
     copies1 = pathcopies(base, c1)
     copies2 = pathcopies(base, c2)
 
+    if not (copies1 or copies2):
+        return {}, {}, {}, {}, {}
+
     inversecopies1 = {}
     inversecopies2 = {}
     for dst, src in copies1.items():
@@ -632,8 +635,6 @@
 
     fullcopy = copies1.copy()
     fullcopy.update(copies2)
-    if not fullcopy:
-        return copy, {}, diverge, renamedelete, {}
 
     if repo.ui.debugflag:
         repo.ui.debug(