D6420: copies: don't filter out copy targets created on other side of merge commit

[martinvonz (Martin von Zweigbergk)]

Closed by commit rHG35d674a3d5db: copies: don't filter out copy targets created on other side of merge commit (authored by martinvonz).
This revision was automatically updated to reflect the committed changes.
This revision was not accepted when it landed; it landed in state "Needs Review".

REPOSITORY
  rHG Mercurial

CHANGES SINCE LAST UPDATE
  https://phab.mercurial-scm.org/D6420?vs=15218&id=15544

CHANGES SINCE LAST ACTION
  https://phab.mercurial-scm.org/D6420/new/

REVISION DETAIL
  https://phab.mercurial-scm.org/D6420

AFFECTED FILES
  mercurial/copies.py
  tests/test-copies.t

CHANGE DETAILS

diff --git a/tests/test-copies.t b/tests/test-copies.t
--- a/tests/test-copies.t
+++ b/tests/test-copies.t
@@ -452,8 +452,9 @@
   y -> z
   $ hg debugpathcopies 1 3
 
-Create x and y, then rename x to z on one side of merge, and rename y to z and modify z on the
-other side.
+Create x and y, then rename x to z on one side of merge, and rename y to z and
+modify z on the other side. When storing copies in the changeset, we don't
+filter out copies whose target was created on the other side of the merge.
   $ newrepo
   $ echo x > x
   $ echo y > y
@@ -494,12 +495,16 @@
   o  0 add x and y
      x y
   $ hg debugpathcopies 1 4
+  y -> z (no-filelog !)
   $ hg debugpathcopies 2 4
+  x -> z (no-filelog !)
   $ hg debugpathcopies 0 4
   x -> z (filelog !)
   y -> z (compatibility !)
   $ hg debugpathcopies 1 5
+  y -> z (no-filelog !)
   $ hg debugpathcopies 2 5
+  x -> z (no-filelog !)
   $ hg debugpathcopies 0 5
   x -> z
 
diff --git a/mercurial/copies.py b/mercurial/copies.py
--- a/mercurial/copies.py
+++ b/mercurial/copies.py
@@ -276,27 +276,22 @@
             # We are tracing copies from both parents
             r, i2, copies2 = heapq.heappop(work)
             copies = {}
-            ctx = repo[r]
-            p1man, p2man = ctx.p1().manifest(), ctx.p2().manifest()
             allcopies = set(copies1) | set(copies2)
             # TODO: perhaps this filtering should be done as long as ctx
             # is merge, whether or not we're tracing from both parent.
             for dst in allcopies:
                 if not match(dst):
                     continue
-                if dst not in copies2:
-                    # Copied on p1 side: mark as copy from p1 side if it didn't
-                    # already exist on p2 side
-                    if dst not in p2man:
-                        copies[dst] = copies1[dst]
-                elif dst not in copies1:
-                    # Copied on p2 side: mark as copy from p2 side if it didn't
-                    # already exist on p1 side
-                    if dst not in p1man:
-                        copies[dst] = copies2[dst]
+                # Unlike when copies are stored in the filelog, we consider
+                # it a copy even if the destination already existed on the
+                # other branch. It's simply too expensive to check if the
+                # file existed in the manifest.
+                if dst in copies1:
+                    # If it was copied on the p1 side, mark it as copied from
+                    # that side, even if it was also copied on the p2 side.
+                    copies[dst] = copies1[dst]
                 else:
-                    # Copied on both sides: mark as copy from p1 side
-                    copies[dst] = copies1[dst]
+                    copies[dst] = copies2[dst]
         else:
             copies = copies1
         if r == b.rev():



To: martinvonz, #hg-reviewers
Cc: mercurial-devel