tests/test-manifest.t

stringutil: emit multiple chunks when pretty printing

This avoids concatenating output inside pprintgen() itself. But
the real reason for this is it will make it easier to add
indentation, as we'll need to account for indentation when emitting
each individual object in a collection.

The verbosity of this code compared to the original is a bit
unfortunate. But I suppose this is the price to pay for having
nice things (streaming and indenting).

We could probably abstract the "print a collection" bits into a
generic function to avoid some duplication. But I'm not
overly inclined to do this.

Differential Revision: https://phab.mercurial-scm.org/D4398

Source bundle was generated with the following script:

# hg init
# echo a > a
# ln -s a l
# hg ci -Ama -d'0 0'
# mkdir b
# echo a > b/a
# chmod +x b/a
# hg ci -Amb -d'1 0'

  $ hg init
  $ hg unbundle "$TESTDIR/bundles/test-manifest.hg"
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 3 changes to 3 files
  new changesets b73562a03cfe:5bdc995175ba
  (run 'hg update' to get a working copy)

The next call is expected to return nothing:

  $ hg manifest

  $ hg co
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg manifest
  a
  b/a
  l

  $ hg files -vr .
           2   a
           2 x b/a
           1 l l
  $ hg files -r . -X b
  a
  l
  $ hg files -T '{path} {size} {flags}\n'
  a 2 
  b/a 2 x
  l 1 l
  $ hg files -T '{path} {node|shortest}\n' -r.
  a 5bdc
  b/a 5bdc
  l 5bdc

  $ hg manifest -v
  644   a
  755 * b/a
  644 @ l
  $ hg manifest -T '{path} {rev}\n'
  a 1
  b/a 1
  l 1

  $ hg manifest --debug
  b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644   a
  b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 755 * b/a
  047b75c6d7a3ef6a2243bd0e99f94f6ea6683597 644 @ l

  $ hg manifest -r 0
  a
  l

  $ hg manifest -r 1
  a
  b/a
  l

  $ hg manifest -r tip
  a
  b/a
  l

  $ hg manifest tip
  a
  b/a
  l

  $ hg manifest --all
  a
  b/a
  l

The next two calls are expected to abort:

  $ hg manifest -r 2
  abort: unknown revision '2'!
  [255]

  $ hg manifest -r tip tip
  abort: please specify just one revision
  [255]