tests/test-glog-topological.t

copies: make _checkcopies handle simple renames in a rotated DAG

This introduces a distinction between "merge base" and
"topological common ancestor". During a regular merge, these two are
identical. Graft, however, performs a merge in a rotated DAG, where the
merge base will not be a common ancestor at all in the
original DAG.

To correctly find copies in case of a graft, we need to take both the
merge base and the topological CA into account, and track any renames
between them in reverse. Fortunately we can detect this in advance,
see comment in the code about "backwards".

This patch only supports finding non-divergent renames contained entirely
between the merge base and the topological CA. Further patches are coming
to support more complex cases.

(Pierre-Yves David was involved in the cleanup of this patch.)

This test file aims at test topological iteration and the various configuration it can has.

  $ cat >> $HGRCPATH << EOF
  > [ui]
  > logtemplate={rev}\n
  > EOF

On this simple example, all topological branch are displayed in turn until we
can finally display 0. this implies skipping from 8 to 3 and coming back to 7
later.

  $ hg init test01
  $ cd test01
  $ hg unbundle $TESTDIR/bundles/remote.hg
  adding changesets
  adding manifests
  adding file changes
  added 9 changesets with 7 changes to 4 files (+1 heads)
  (run 'hg heads' to see heads, 'hg merge' to merge)

  $ hg log -G
  o  8
  |
  | o  7
  | |
  | o  6
  | |
  | o  5
  | |
  | o  4
  | |
  o |  3
  | |
  o |  2
  | |
  o |  1
  |/
  o  0
  

(display all nodes)

  $ hg log -G -r 'sort(all(), topo)'
  o  8
  |
  o  3
  |
  o  2
  |
  o  1
  |
  | o  7
  | |
  | o  6
  | |
  | o  5
  | |
  | o  4
  |/
  o  0
  

(display nodes filtered by log options)

  $ hg log -G -r 'sort(all(), topo)' -k '.3'
  o  8
  |
  o  3
  |
  ~
  o  7
  |
  o  6
  |
  ~

(revset skipping nodes)

  $ hg log -G --rev 'sort(not (2+6), topo)'
  o  8
  |
  o  3
  :
  o  1
  |
  | o  7
  | :
  | o  5
  | |
  | o  4
  |/
  o  0
  

(begin) from the other branch

  $ hg log -G -r 'sort(all(), topo, topo.firstbranch=5)'
  o  7
  |
  o  6
  |
  o  5
  |
  o  4
  |
  | o  8
  | |
  | o  3
  | |
  | o  2
  | |
  | o  1
  |/
  o  0