tests/test-revlog-packentry.t

store: encode first period or space in filenames (issue1713)

- Mac OS X has problems with filenames starting with '._'
  (e.g. '.FOO' -> '._f_o_o' is now encoded as '~2e_f_o_o')

- Explorer of Windows Vista and Windows 7 strip leading spaces of
  path elements of filenames when copying trees

Above problems are avoided by encoding the first space (as '~20') or
period (as '~2e') of all path elements.

This introduces a new entry 'dotencode' in .hg/requires, that is,
a new repository filename layout (inside .hg/store).

Newly created repositories require 'dotencode' by default. Specifying

  [format]
  dotencode = False

in a config file will use the old format instead.

Prior Mercurial versions will abort with the message

   abort: requirement 'dotencode' not supported!

when trying to access a local repository that requires 'dotencode'.

New 'dotencode' repositories can be converted to the previous
repository format with

  hg --config format.dotencode=0 clone --pull repoA repoB

  $ hg init repo
  $ cd repo

  $ touch foo
  $ hg ci -Am 'add foo'
  adding foo

  $ hg up -C null
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

this should be stored as a delta against rev 0

  $ echo foo bar baz > foo
  $ hg ci -Am 'add foo again'
  adding foo
  created new head

  $ hg debugindex .hg/store/data/foo.i
     rev    offset  length   base linkrev nodeid       p1           p2
       0         0       0      0       0 b80de5d13875 000000000000 000000000000
       1         0      24      0       1 0376abec49b8 000000000000 000000000000