tests/test-bundle-phases.t

filelog: wrap revlog instead of inheriting it (API)

The revlog base class exposes a ton of methods. Inheriting the
revlog class for filelog will make it difficult to expose a
clean interface. There will be abstraction violations.

This commit breaks the inheritance of revlog by the filelog
class. Filelog instances now contain a reference to a revlog
instance. Various properties and methods are now proxied to
that instance.

There is precedence for doing this: manifestlog does something
similar. Although, manifestlog has a cleaner interface than
filelog. We'll get there with filelog...

The new filelog class exposes a handful of extra properties and
methods that aren't part of the declared filelog interface.
Every extra item was added in order to get a test to pass. The
set of tests that failed without these extra proxies has
significant overlap with the set of tests that don't work with
the simple store repo. There should be no surprise there.

Hopefully the hardest part about this commit to review are the
changes to bundlerepo and unionrepo. Both repository types
define a custom revlog or revlog-like class and then have a
custom filelog that inherits from both filelog and their custom
revlog. This code has been changed so the filelog types don't
inherit from revlog. Instead, they replace the revlog instance
on the created filelog. This is super hacky. I plan to fix this
in a future commit by parameterizing filelog.__init__.

Because Python function call overhead is a thing, this change
could impact performance by introducing a nearly empty proxy
function for various methods and properties. I would gladly
measure the performance impact of it, but I'm not sure what
operations have tight loops over filelog attribute lookups
or function calls. I know some of the DAG traversal code can
be sensitive about the performance of e.g. parentrevs(). However,
many of these functions are implemented on the revlog class and
therefore have direct access to self.parentrevs() and aren't
going through a proxy.

.. api::

   filelog.filelog is now a standalone class and doesn't inherit
   from revlog. Instead, it wraps a revlog instance at self._revlog.
   This change was made in an attempt to formalize storage APIs and
   prevent revlog implementation details leaking through to callers.

Differential Revision: https://phab.mercurial-scm.org/D3154

  $ cat >> $HGRCPATH <<EOF
  > [experimental]
  > bundle-phases=yes
  > [extensions]
  > strip=
  > drawdag=$TESTDIR/drawdag.py
  > EOF

Set up repo with linear history
  $ hg init linear
  $ cd linear
  $ hg debugdrawdag <<'EOF'
  > E
  > |
  > D
  > |
  > C
  > |
  > B
  > |
  > A
  > EOF
  $ hg phase --public A
  $ hg phase --force --secret D
  $ hg log -G -T '{desc} {phase}\n'
  o  E secret
  |
  o  D secret
  |
  o  C draft
  |
  o  B draft
  |
  o  A public
  
Phases are restored when unbundling
  $ hg bundle --base B -r E bundle
  3 changesets found
  $ hg debugbundle bundle
  Stream params: {Compression: BZ}
  changegroup -- {nbchanges: 3, targetphase: 2, version: 02}
      26805aba1e600a82e93661149f2313866a221a7b
      f585351a92f85104bff7c284233c338b10eb1df7
      9bc730a19041f9ec7cb33c626e811aa233efb18c
  cache:rev-branch-cache -- {}
  phase-heads -- {}
      26805aba1e600a82e93661149f2313866a221a7b draft
  $ hg strip --no-backup C
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{desc} {phase}\n'
  o  E secret
  |
  o  D secret
  |
  o  C draft
  |
  o  B draft
  |
  o  A public
  
Root revision's phase is preserved
  $ hg bundle -a bundle
  5 changesets found
  $ hg strip --no-backup A
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{desc} {phase}\n'
  o  E secret
  |
  o  D secret
  |
  o  C draft
  |
  o  B draft
  |
  o  A public
  
Completely public history can be restored
  $ hg phase --public E
  $ hg bundle -a bundle
  5 changesets found
  $ hg strip --no-backup A
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{desc} {phase}\n'
  o  E public
  |
  o  D public
  |
  o  C public
  |
  o  B public
  |
  o  A public
  
Direct transition from public to secret can be restored
  $ hg phase --secret --force D
  $ hg bundle -a bundle
  5 changesets found
  $ hg strip --no-backup A
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{desc} {phase}\n'
  o  E secret
  |
  o  D secret
  |
  o  C public
  |
  o  B public
  |
  o  A public
  
Revisions within bundle preserve their phase even if parent changes its phase
  $ hg phase --draft --force B
  $ hg bundle --base B -r E bundle
  3 changesets found
  $ hg strip --no-backup C
  $ hg phase --public B
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{desc} {phase}\n'
  o  E secret
  |
  o  D secret
  |
  o  C draft
  |
  o  B public
  |
  o  A public
  
Phase of ancestors of stripped node get advanced to accommodate child
  $ hg bundle --base B -r E bundle
  3 changesets found
  $ hg strip --no-backup C
  $ hg phase --force --secret B
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{desc} {phase}\n'
  o  E secret
  |
  o  D secret
  |
  o  C draft
  |
  o  B draft
  |
  o  A public
  
Unbundling advances phases of changesets even if they were already in the repo.
To test that, create a bundle of everything in draft phase and then unbundle
to see that secret becomes draft, but public remains public.
  $ hg phase --draft --force A
  $ hg phase --draft E
  $ hg bundle -a bundle
  5 changesets found
  $ hg phase --public A
  $ hg phase --secret --force E
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{desc} {phase}\n'
  o  E draft
  |
  o  D draft
  |
  o  C draft
  |
  o  B draft
  |
  o  A public
  
Unbundling change in the middle of a stack does not affect later changes
  $ hg strip --no-backup E
  $ hg phase --secret --force D
  $ hg log -G -T '{desc} {phase}\n'
  o  D secret
  |
  o  C draft
  |
  o  B draft
  |
  o  A public
  
  $ hg bundle --base A -r B bundle
  1 changesets found
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{desc} {phase}\n'
  o  D secret
  |
  o  C draft
  |
  o  B draft
  |
  o  A public
  

  $ cd ..

Set up repo with non-linear history
  $ hg init non-linear
  $ cd non-linear
  $ hg debugdrawdag <<'EOF'
  > D E
  > |\|
  > B C
  > |/
  > A
  > EOF
  $ hg phase --public C
  $ hg phase --force --secret B
  $ hg log -G -T '{node|short} {desc} {phase}\n'
  o  03ca77807e91 E draft
  |
  | o  4e4f9194f9f1 D secret
  |/|
  o |  dc0947a82db8 C public
  | |
  | o  112478962961 B secret
  |/
  o  426bada5c675 A public
  

Restore bundle of entire repo
  $ hg bundle -a bundle
  5 changesets found
  $ hg debugbundle bundle
  Stream params: {Compression: BZ}
  changegroup -- {nbchanges: 5, targetphase: 2, version: 02}
      426bada5c67598ca65036d57d9e4b64b0c1ce7a0
      112478962961147124edd43549aedd1a335e44bf
      dc0947a82db884575bb76ea10ac97b08536bfa03
      4e4f9194f9f181c57f62e823e8bdfa46ab9e4ff4
      03ca77807e919db8807c3749086dc36fb478cac0
  cache:rev-branch-cache -- {}
  phase-heads -- {}
      dc0947a82db884575bb76ea10ac97b08536bfa03 public
      03ca77807e919db8807c3749086dc36fb478cac0 draft
  $ hg strip --no-backup A
  $ hg unbundle -q bundle
  $ rm bundle
  $ hg log -G -T '{node|short} {desc} {phase}\n'
  o  03ca77807e91 E draft
  |
  | o  4e4f9194f9f1 D secret
  |/|
  o |  dc0947a82db8 C public
  | |
  | o  112478962961 B secret
  |/
  o  426bada5c675 A public
  

  $ hg bundle --base 'A + C' -r D bundle
  2 changesets found
  $ hg debugbundle bundle
  Stream params: {Compression: BZ}
  changegroup -- {nbchanges: 2, targetphase: 2, version: 02}
      112478962961147124edd43549aedd1a335e44bf
      4e4f9194f9f181c57f62e823e8bdfa46ab9e4ff4
  cache:rev-branch-cache -- {}
  phase-heads -- {}
  $ rm bundle

  $ hg bundle --base A -r D bundle
  3 changesets found
  $ hg debugbundle bundle
  Stream params: {Compression: BZ}
  changegroup -- {nbchanges: 3, targetphase: 2, version: 02}
      112478962961147124edd43549aedd1a335e44bf
      dc0947a82db884575bb76ea10ac97b08536bfa03
      4e4f9194f9f181c57f62e823e8bdfa46ab9e4ff4
  cache:rev-branch-cache -- {}
  phase-heads -- {}
      dc0947a82db884575bb76ea10ac97b08536bfa03 public
  $ rm bundle

  $ hg bundle --base 'B + C' -r 'D + E' bundle
  2 changesets found
  $ hg debugbundle bundle
  Stream params: {Compression: BZ}
  changegroup -- {nbchanges: 2, targetphase: 2, version: 02}
      4e4f9194f9f181c57f62e823e8bdfa46ab9e4ff4
      03ca77807e919db8807c3749086dc36fb478cac0
  cache:rev-branch-cache -- {}
  phase-heads -- {}
      03ca77807e919db8807c3749086dc36fb478cac0 draft
  $ rm bundle