tests/test-narrow-acl.t

revlog: make the index always return the same tuple

It is simpler to manage the diferrence in on disk format in the internal index
code itself and lets the rest of the code always handle the same object.

This will become even more important when the data we store will be entirely
different (for example the changelog does not need the "linkrev" field.

We start with item reading, we will deal with item writing in the next
changesets.

Differential Revision: https://phab.mercurial-scm.org/D10568

Make a narrow clone then archive it
  $ . "$TESTDIR/narrow-library.sh"

  $ hg init master
  $ cd master

  $ for x in `$TESTDIR/seq.py 3`; do
  >   echo $x > "f$x"
  >   hg add "f$x"
  >   hg commit -m "Add $x"
  > done
  $ cat >> .hg/hgrc << EOF
  > [narrowacl]
  > default.includes=f1 f2
  > EOF
  $ hg serve -a localhost -p $HGPORT1 -d --pid-file=hg.pid
  $ cat hg.pid >> "$DAEMON_PIDS"

  $ cd ..
  $ hg clone http://localhost:$HGPORT1 narrowclone1
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 2 changes to 2 files
  new changesets * (glob)
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

The clone directory should only contain f1 and f2
  $ ls -A -1 narrowclone1 | sort
  .hg
  f1
  f2

Requirements should contain narrowhg
  $ cat narrowclone1/.hg/requires | grep narrowhg
  narrowhg-experimental

NarrowHG should track f1 and f2
  $ hg -R narrowclone1 tracked
  I path:f1
  I path:f2