tests/test-generaldelta.t

baseset: drop custom __sub__ method

This add method is enforcing non-laziness, disabling multiple optimisations.

Benchmarks do not spot any significant difference but real usecase may. This
will also be important for further improvements to addset later in this series.

Check whether size of generaldelta revlog is not bigger than its
regular equivalent. Test would fail if generaldelta was naive
implementation of parentdelta: third manifest revision would be fully
inserted due to big distance from its paren revision (zero).

  $ hg init repo
  $ cd repo
  $ echo foo > foo
  $ echo bar > bar
  $ hg commit -q -Am boo
  $ hg clone --pull . ../gdrepo -q --config format.generaldelta=yes
  $ for r in 1 2 3; do
  >   echo $r > foo
  >   hg commit -q -m $r
  >   hg up -q -r 0
  >   hg pull . -q -r $r -R ../gdrepo
  > done

  $ cd ..
  >>> import os
  >>> regsize = os.stat("repo/.hg/store/00manifest.i").st_size
  >>> gdsize = os.stat("gdrepo/.hg/store/00manifest.i").st_size
  >>> if regsize < gdsize:
  ...     print 'generaldata increased size of manifest'