tests/test-rebase-brute-force.t

test-revlog: update the patch used to test delta againts nullrev

We need to be careful to not create invalid delta for changelog. Changelog is
special because it does not use any delta in practice and don't use general
delta in its format.

Using the new patch will help use to test more cases.

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > drawdag=$TESTDIR/drawdag.py
  > bruterebase=$TESTDIR/bruterebase.py
  > [experimental]
  > evolution.createmarkers=True
  > evolution.allowunstable=True
  > EOF
  $ init() {
  >   N=`expr ${N:-0} + 1`
  >   cd $TESTTMP && hg init repo$N && cd repo$N
  >   hg debugdrawdag
  > }

Source looks like "N"

  $ init <<'EOS'
  > C D
  > |\|
  > A B Z
  > EOS

  $ hg debugbruterebase 'all()-Z' Z
     A: A':Z
     B: B':Z
    AB: A':Z B':Z
     C: ABORT: cannot rebase 3:a35c07e8a2a4 without moving at least one of its parents
    AC: A':Z C':A'B
    BC: B':Z C':B'A
   ABC: A':Z B':Z C':A'B'
     D: D':Z
    AD: A':Z D':Z
    BD: B':Z D':B'
   ABD: A':Z B':Z D':B'
    CD: ABORT: cannot rebase 3:a35c07e8a2a4 without moving at least one of its parents
   ACD: A':Z C':A'B D':Z
   BCD: B':Z C':B'A D':B'
  ABCD: A':Z B':Z C':A'B' D':B'

Moving backwards

  $ init <<'EOS'
  > C
  > |\
  > A B
  > |
  > Z
  > EOS
  $ hg debugbruterebase 'all()-Z' Z
    B: B':Z
    A: 
   BA: B':Z
    C: ABORT: cannot rebase 3:b8d7149b562b without moving at least one of its parents
   BC: B':Z C':B'A
   AC: 
  BAC: B':Z C':B'A