view tests/test-revlog-v2.t @ 35012:d80380ba8e7d

changegroup: use any node, not min(), in treemanifest's generatemanifests

This is fixing quadratic behavior, which is probably not noticeable in the
common case, but if a very large directory gets added here, it can get pretty
bad. This was noticed because we had some pushes that spent >25s in changegroup
generation calling min() here, according to profiling.

The original reasoning for min() being used in 829d369fc5a8 was that, at that
point in the series, we were adding almost everything to tmfnodes during the
first iteration through the loop , so we needed to avoid sending child
directories before parents. Later changes made it so that the child directories
were added only when we visited the parent directory (not all of them on the
first iteration), so this is no longer necessary - there won't be any child
directories in tmfnodes before the parents have been sent.

This does mean that the manifests are now exchanged unordered, whereas
previously we would essentially do [a, b, b/c, b/c/d, e], we now can send a, b,
and e in any order; b/c must still follow b, and b/c/d must still follow b/c.

Differential Revision: https://phab.mercurial-scm.org/D1351

A repo with unknown revlogv2 requirement string cannot be opened

  $ hg init invalidreq
  $ cd invalidreq
  $ echo exp-revlogv2.unknown >> .hg/requires
  $ hg log
  abort: repository requires features unknown to this Mercurial: exp-revlogv2.unknown!
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]
  $ cd ..

Can create and open repo with revlog v2 requirement

  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > revlogv2 = enable-unstable-format-and-corrupt-my-data
  > EOF

  $ hg init empty-repo
  $ cd empty-repo
  $ cat .hg/requires
  dotencode
  exp-revlogv2.0
  fncache
  store

  $ hg log

Unknown flags to revlog are rejected

  >>> with open('.hg/store/00changelog.i', 'wb') as fh:
  ...     fh.write('\x00\x04\xde\xad')

  $ hg log
  abort: unknown flags (0x04) in version 57005 revlog 00changelog.i!
  [255]

  $ cd ..

Writing a simple revlog v2 works

  $ hg init simple
  $ cd simple
  $ touch foo
  $ hg -q commit -A -m initial

  $ hg log
  changeset:   0:96ee1d7354c4
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     initial
  
Header written as expected (changelog always disables generaldelta)

  $ f --hexdump --bytes 4 .hg/store/00changelog.i
  .hg/store/00changelog.i:
  0000: 00 01 de ad                                     |....|

  $ f --hexdump --bytes 4 .hg/store/data/foo.i
  .hg/store/data/foo.i:
  0000: 00 03 de ad                                     |....|