copies: add test that makes both the merging csets dirty and run w/o error

This series of patches is to cover a case in fullcopytracing algorithms
where both the merging csets are not descendant of merge base.

In this algorithm we call a merging cset "dirty" if that cset is not the
descendant of merge base. That said, added test in this patch cover case
when both the merging csets are "dirty".

Actually this case of "both dirty" was encountered by Pulkit when he was
working on content-divergence where it is possible that both the csets
are not descendant of merging base.
For reference you can look into: https://phab.mercurial-scm.org/D3896

As this test run fine without any error and correctly traced the copies, I
added this test to make sure that it doesn't break even after I will modify
some code in next patches to fix an error. Next patch adds the tests where
this algorithm throws an error for the same case of "both dirty".

Differential Revision: https://phab.mercurial-scm.org/D5961

tests/test-copies.t

@@ -1,493 +1,554
 #testcases filelog compatibility
 
   $ cat >> $HGRCPATH << EOF
   > [alias]
   > l = log -G -T '{rev} {desc}\n{files}\n'
   > EOF
 
 #if compatibility
   $ cat >> $HGRCPATH << EOF
   > [experimental]
   > copies.read-from = compatibility
   > EOF
 #endif
 
   $ REPONUM=0
   $ newrepo() {
   >     cd $TESTTMP
   >     REPONUM=`expr $REPONUM + 1`
   >     hg init repo-$REPONUM
   >     cd repo-$REPONUM
   > }
 
 Simple rename case
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg mv x y
   $ hg debugp1copies
   x -> y
   $ hg debugp2copies
   $ hg ci -m 'rename x to y'
   $ hg l
   @  1 rename x to y
   |  x y
   o  0 add x
      x
   $ hg debugp1copies -r 1
   x -> y
   $ hg debugpathcopies 0 1
   x -> y
   $ hg debugpathcopies 1 0
   y -> x
 Test filtering copies by path. We do filtering by destination.
   $ hg debugpathcopies 0 1 x
   $ hg debugpathcopies 1 0 x
   y -> x
   $ hg debugpathcopies 0 1 y
   x -> y
   $ hg debugpathcopies 1 0 y
 
 Copy a file onto another file
   $ newrepo
   $ echo x > x
   $ echo y > y
   $ hg ci -Aqm 'add x and y'
   $ hg cp -f x y
   $ hg debugp1copies
   x -> y
   $ hg debugp2copies
   $ hg ci -m 'copy x onto y'
   $ hg l
   @  1 copy x onto y
   |  y
   o  0 add x and y
      x y
   $ hg debugp1copies -r 1
   x -> y
 Incorrectly doesn't show the rename
   $ hg debugpathcopies 0 1
 
 Copy a file onto another file with same content. If metadata is stored in changeset, this does not
 produce a new filelog entry. The changeset's "files" entry should still list the file.
   $ newrepo
   $ echo x > x
   $ echo x > x2
   $ hg ci -Aqm 'add x and x2 with same content'
   $ hg cp -f x x2
   $ hg ci -m 'copy x onto x2'
   $ hg l
   @  1 copy x onto x2
   |  x2
   o  0 add x and x2 with same content
      x x2
   $ hg debugp1copies -r 1
   x -> x2
 Incorrectly doesn't show the rename
   $ hg debugpathcopies 0 1
 
 Copy a file, then delete destination, then copy again. This does not create a new filelog entry.
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg cp x y
   $ hg ci -m 'copy x to y'
   $ hg rm y
   $ hg ci -m 'remove y'
   $ hg cp -f x y
   $ hg ci -m 'copy x onto y (again)'
   $ hg l
   @  3 copy x onto y (again)
   |  y
   o  2 remove y
   |  y
   o  1 copy x to y
   |  y
   o  0 add x
      x
   $ hg debugp1copies -r 3
   x -> y
   $ hg debugpathcopies 0 3
   x -> y
 
 Rename file in a loop: x->y->z->x
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg mv x y
   $ hg debugp1copies
   x -> y
   $ hg debugp2copies
   $ hg ci -m 'rename x to y'
   $ hg mv y z
   $ hg ci -m 'rename y to z'
   $ hg mv z x
   $ hg ci -m 'rename z to x'
   $ hg l
   @  3 rename z to x
   |  x z
   o  2 rename y to z
   |  y z
   o  1 rename x to y
   |  x y
   o  0 add x
      x
   $ hg debugpathcopies 0 3
 
 Copy x to y, then remove y, then add back y. With copy metadata in the changeset, this could easily
 end up reporting y as copied from x (if we don't unmark it as a copy when it's removed).
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg mv x y
   $ hg ci -m 'rename x to y'
   $ hg rm y
   $ hg ci -qm 'remove y'
   $ echo x > y
   $ hg ci -Aqm 'add back y'
   $ hg l
   @  3 add back y
   |  y
   o  2 remove y
   |  y
   o  1 rename x to y
   |  x y
   o  0 add x
      x
   $ hg debugp1copies -r 3
   $ hg debugpathcopies 0 3
 
 Copy x to z, then remove z, then copy x2 (same content as x) to z. With copy metadata in the
 changeset, the two copies here will have the same filelog entry, so ctx['z'].introrev() might point
 to the first commit that added the file. We should still report the copy as being from x2.
   $ newrepo
   $ echo x > x
   $ echo x > x2
   $ hg ci -Aqm 'add x and x2 with same content'
   $ hg cp x z
   $ hg ci -qm 'copy x to z'
   $ hg rm z
   $ hg ci -m 'remove z'
   $ hg cp x2 z
   $ hg ci -m 'copy x2 to z'
   $ hg l
   @  3 copy x2 to z
   |  z
   o  2 remove z
   |  z
   o  1 copy x to z
   |  z
   o  0 add x and x2 with same content
      x x2
   $ hg debugp1copies -r 3
   x2 -> z
   $ hg debugpathcopies 0 3
   x2 -> z
 
 Create x and y, then rename them both to the same name, but on different sides of a fork
   $ newrepo
   $ echo x > x
   $ echo y > y
   $ hg ci -Aqm 'add x and y'
   $ hg mv x z
   $ hg ci -qm 'rename x to z'
   $ hg co -q 0
   $ hg mv y z
   $ hg ci -qm 'rename y to z'
   $ hg l
   @  2 rename y to z
   |  y z
   | o  1 rename x to z
   |/   x z
   o  0 add x and y
      x y
   $ hg debugpathcopies 1 2
   z -> x
   y -> z
 
 Fork renames x to y on one side and removes x on the other
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg mv x y
   $ hg ci -m 'rename x to y'
   $ hg co -q 0
   $ hg rm x
   $ hg ci -m 'remove x'
   created new head
   $ hg l
   @  2 remove x
   |  x
   | o  1 rename x to y
   |/   x y
   o  0 add x
      x
   $ hg debugpathcopies 1 2
 
 Copies via null revision (there shouldn't be any)
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg cp x y
   $ hg ci -m 'copy x to y'
   $ hg co -q null
   $ echo x > x
   $ hg ci -Aqm 'add x (again)'
   $ hg l
   @  2 add x (again)
      x
   o  1 copy x to y
   |  y
   o  0 add x
      x
   $ hg debugpathcopies 1 2
   $ hg debugpathcopies 2 1
 
 Merge rename from other branch
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg mv x y
   $ hg ci -m 'rename x to y'
   $ hg co -q 0
   $ echo z > z
   $ hg ci -Aqm 'add z'
   $ hg merge -q 1
   $ hg debugp1copies
   $ hg debugp2copies
   $ hg ci -m 'merge rename from p2'
   $ hg l
   @    3 merge rename from p2
   |\   x
   | o  2 add z
   | |  z
   o |  1 rename x to y
   |/   x y
   o  0 add x
      x
 Perhaps we should indicate the rename here, but `hg status` is documented to be weird during
 merges, so...
   $ hg debugp1copies -r 3
   $ hg debugp2copies -r 3
   $ hg debugpathcopies 0 3
   x -> y
   $ hg debugpathcopies 1 2
   y -> x
   $ hg debugpathcopies 1 3
   $ hg debugpathcopies 2 3
   x -> y
 
 Copy file from either side in a merge
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg co -q null
   $ echo y > y
   $ hg ci -Aqm 'add y'
   $ hg merge -q 0
   $ hg cp y z
   $ hg debugp1copies
   y -> z
   $ hg debugp2copies
   $ hg ci -m 'copy file from p1 in merge'
   $ hg co -q 1
   $ hg merge -q 0
   $ hg cp x z
   $ hg debugp1copies
   $ hg debugp2copies
   x -> z
   $ hg ci -qm 'copy file from p2 in merge'
   $ hg l
   @    3 copy file from p2 in merge
   |\   z
   +---o  2 copy file from p1 in merge
   | |/   z
   | o  1 add y
   |    y
   o  0 add x
      x
   $ hg debugp1copies -r 2
   y -> z
   $ hg debugp2copies -r 2
   $ hg debugpathcopies 1 2
   y -> z
   $ hg debugpathcopies 0 2
   $ hg debugp1copies -r 3
   $ hg debugp2copies -r 3
   x -> z
   $ hg debugpathcopies 1 3
   $ hg debugpathcopies 0 3
   x -> z
 
 Copy file that exists on both sides of the merge, same content on both sides
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x on branch 1'
   $ hg co -q null
   $ echo x > x
   $ hg ci -Aqm 'add x on branch 2'
   $ hg merge -q 0
   $ hg cp x z
   $ hg debugp1copies
   x -> z
   $ hg debugp2copies
   $ hg ci -qm 'merge'
   $ hg l
   @    2 merge
   |\   z
   | o  1 add x on branch 2
   |    x
   o  0 add x on branch 1
      x
   $ hg debugp1copies -r 2
   x -> z
   $ hg debugp2copies -r 2
 It's a little weird that it shows up on both sides
   $ hg debugpathcopies 1 2
   x -> z
   $ hg debugpathcopies 0 2
   x -> z (filelog !)
 
 Copy file that exists on both sides of the merge, different content
   $ newrepo
   $ echo branch1 > x
   $ hg ci -Aqm 'add x on branch 1'
   $ hg co -q null
   $ echo branch2 > x
   $ hg ci -Aqm 'add x on branch 2'
   $ hg merge -q 0
   warning: conflicts while merging x! (edit, then use 'hg resolve --mark')
   [1]
   $ echo resolved > x
   $ hg resolve -m x
   (no more unresolved files)
   $ hg cp x z
   $ hg debugp1copies
   x -> z
   $ hg debugp2copies
   $ hg ci -qm 'merge'
   $ hg l
   @    2 merge
   |\   x z
   | o  1 add x on branch 2
   |    x
   o  0 add x on branch 1
      x
   $ hg debugp1copies -r 2
   $ hg debugp2copies -r 2
   x -> z
   $ hg debugpathcopies 1 2
   $ hg debugpathcopies 0 2
   x -> z
 
 Copy x->y on one side of merge and copy x->z on the other side. Pathcopies from one parent
 of the merge to the merge should include the copy from the other side.
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg cp x y
   $ hg ci -qm 'copy x to y'
   $ hg co -q 0
   $ hg cp x z
   $ hg ci -qm 'copy x to z'
   $ hg merge -q 1
   $ hg ci -m 'merge copy x->y and copy x->z'
   $ hg l
   @    3 merge copy x->y and copy x->z
   |\
   | o  2 copy x to z
   | |  z
   o |  1 copy x to y
   |/   y
   o  0 add x
      x
   $ hg debugp1copies -r 3
   $ hg debugp2copies -r 3
   $ hg debugpathcopies 2 3
   x -> y
   $ hg debugpathcopies 1 3
   x -> z
 
 Copy x to y on one side of merge, create y and rename to z on the other side. Pathcopies from the
 first side should not include the y->z rename since y didn't exist in the merge base.
   $ newrepo
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg cp x y
   $ hg ci -qm 'copy x to y'
   $ hg co -q 0
   $ echo y > y
   $ hg ci -Aqm 'add y'
   $ hg mv y z
   $ hg ci -m 'rename y to z'
   $ hg merge -q 1
   $ hg ci -m 'merge'
   $ hg l
   @    4 merge
   |\
   | o  3 rename y to z
   | |  y z
   | o  2 add y
   | |  y
   o |  1 copy x to y
   |/   y
   o  0 add x
      x
   $ hg debugp1copies -r 3
   y -> z
   $ hg debugp2copies -r 3
   $ hg debugpathcopies 2 3
   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.
   $ newrepo
   $ echo x > x
   $ echo y > y
   $ hg ci -Aqm 'add x and y'
   $ hg mv x z
   $ hg ci -qm 'rename x to z'
   $ hg co -q 0
   $ hg mv y z
   $ hg ci -qm 'rename y to z'
   $ echo z >> z
   $ hg ci -m 'modify z'
   $ hg merge -q 1
   warning: conflicts while merging z! (edit, then use 'hg resolve --mark')
   [1]
   $ echo z > z
   $ hg resolve -qm z
   $ hg ci -m 'merge 1 into 3'
 Try merging the other direction too
   $ hg co -q 1
   $ hg merge -q 3
   warning: conflicts while merging z! (edit, then use 'hg resolve --mark')
   [1]
   $ echo z > z
   $ hg resolve -qm z
   $ hg ci -m 'merge 3 into 1'
   created new head
   $ hg l
   @    5 merge 3 into 1
   |\   y z
   +---o  4 merge 1 into 3
   | |/   x z
   | o  3 modify z
   | |  z
   | o  2 rename y to z
   | |  y z
   o |  1 rename x to z
   |/   x z
   o  0 add x and y
      x y
   $ hg debugpathcopies 1 4
   $ hg debugpathcopies 2 4
   $ hg debugpathcopies 0 4
   x -> z (filelog !)
   y -> z (compatibility !)
   $ hg debugpathcopies 1 5
   $ hg debugpathcopies 2 5
   $ hg debugpathcopies 0 5
   x -> z
 
+
+Test for a case in fullcopytracing algorithm where both the merging csets are
+"dirty"; where a dirty cset means that cset is descendant of merge base. This
+test reflect that for this particular case this algorithm correctly find the copies:
+
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > evolution.createmarkers=True
+  > evolution.allowunstable=True
+  > EOF
+
+  $ newrepo
+  $ echo a > a
+  $ hg add a
+  $ hg ci -m "added a"
+  $ echo b > b
+  $ hg add b
+  $ hg ci -m "added b"
+
+  $ hg mv b b1
+  $ hg ci -m "rename b to b1"
+
+  $ hg up ".^"
+  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  $ echo d > d
+  $ hg add d
+  $ hg ci -m "added d"
+  created new head
+
+  $ echo baba >> b
+  $ hg ci --amend -m "added d, modified b"
+
+  $ hg l --hidden
+  @  4 added d, modified b
+  |  b d
+  | x  3 added d
+  |/   d
+  | o  2 rename b to b1
+  |/   b b1
+  o  1 added b
+  |  b
+  o  0 added a
+     a
+
+Grafting revision 4 on top of revision 2, showing that it respect the rename:
+
+  $ hg up 2 -q
+  $ hg graft -r 4 --base 3 --hidden
+  grafting 4:af28412ec03c "added d, modified b" (tip)
+  merging b1 and b to b1
+
+  $ hg l -l1 -p
+  @  5 added d, modified b
+  |  b1
+  ~  diff -r 5a4825cc2926 -r 94a2f1a0e8e2 b1
+     --- a/b1	Thu Jan 01 00:00:00 1970 +0000
+     +++ b/b1	Thu Jan 01 00:00:00 1970 +0000
+     @@ -1,1 +1,2 @@
+      b
+     +baba
+