view tests/test-convert-bzr-merges.t @ 49000:dd6b67d5c256 stable

rust: fix unsound `OwningDirstateMap`

As per the previous patch, `OwningDirstateMap` is unsound. Self-referential
structs are difficult to implement correctly in Rust since the compiler is
free to move structs around as much as it wants to. They are also very rarely
needed in practice, so the state-of-the-art on how they should be done within
the Rust rules is still a bit new.

The crate `ouroboros` is an attempt at providing a safe way (in the Rust sense)
of declaring self-referential structs. It is getting a lot attention and was
improved very quickly when soundness issues were found in the past: rather than
relying on our own (limited) review circle, we might as well use the de-facto
common crate to fix this problem. This will give us a much better chance of
finding issues should any new ones be discovered as well as the benefit of
fewer `unsafe` APIs of our own.

I was starting to think about how I would present a safe API to the old struct
but soon realized that the callback-based approach was already done in
`ouroboros`, along with a lot more care towards refusing incorrect structs.

In short: we don't return a mutable reference to the `DirstateMap` anymore, we
expect users of its API to pass a `FnOnce` that takes the map as an argument.
This allows our `OwningDirstateMap` to control the input and output lifetimes
of the code that modifies it to prevent such issues.

Changing to `ouroboros` meant changing every API with it, but it is relatively
low churn in the end. It correctly identified the example buggy modification of
`copy_map_insert` outlined in the previous patch as violating the borrow rules.

Differential Revision: https://phab.mercurial-scm.org/D12429

#require bzr

N.B. bzr 1.13 has a bug that breaks this test.  If you see this
test fail, check your bzr version.  Upgrading to bzr 1.13.1
should fix it.

  $ . "$TESTDIR/bzr-definitions"

test multiple merges at once

  $ mkdir test-multimerge
  $ cd test-multimerge
  $ brz init -q source
  $ cd source
  $ echo content > file
  $ echo text > rename_me
  $ brz add -q file rename_me
  $ brz commit -q -m 'Initial add' '--commit-time=2009-10-10 08:00:00 +0100'
  $ cd ..
  $ brz branch -q source source-branch1
  $ cd source-branch1
  $ echo morecontent >> file
  $ echo evenmorecontent > file-branch1
  $ brz add -q file-branch1
  $ brz commit -q -m 'Added branch1 file' '--commit-time=2009-10-10 08:00:01 +0100'
  $ cd ../source
  $ sleep 1
  $ echo content > file-parent
  $ brz add -q file-parent
  $ brz commit -q -m 'Added parent file' '--commit-time=2009-10-10 08:00:02 +0100'
  $ cd ..
  $ brz branch -q source source-branch2
  $ cd source-branch2
  $ echo somecontent > file-branch2
  $ brz add -q file-branch2
  $ brz mv -q rename_me renamed
  $ echo change > renamed
  $ brz commit -q -m 'Added brach2 file' '--commit-time=2009-10-10 08:00:03 +0100'
  $ sleep 1
  $ cd ../source
  $ brz merge -q ../source-branch1
  $ brz merge -q --force ../source-branch2
  $ brz commit -q -m 'Merged branches' '--commit-time=2009-10-10 08:00:04 +0100'
  $ cd ..

BUG: file-branch2 should not be added in rev 4, and the rename_me -> renamed
move should be recorded in the fixup merge.
  $ hg convert --datesort --config convert.bzr.saverev=False source source-hg
  initializing destination source-hg repository
  scanning source...
  sorting...
  converting...
  4 Initial add
  3 Added branch1 file
  2 Added parent file
  1 Added brach2 file
  0 Merged branches
  warning: can't find ancestor for 'renamed' copied from 'rename_me'!
  $ glog -R source-hg
  o    5@source "(octopus merge fixup)" files+: [], files-: [], files: [renamed]
  |\
  | o    4@source "Merged branches" files+: [file-branch2 renamed], files-: [rename_me], files: []
  | |\
  o---+  3@source-branch2 "Added brach2 file" files+: [file-branch2 renamed], files-: [rename_me], files: []
   / /
  | o  2@source "Added parent file" files+: [file-parent], files-: [], files: []
  | |
  o |  1@source-branch1 "Added branch1 file" files+: [file-branch1], files-: [], files: [file]
  |/
  o  0@source "Initial add" files+: [file rename_me], files-: [], files: []
  
  $ manifest source-hg tip
  % manifest of tip
  644   file
  644   file-branch1
  644   file-branch2
  644   file-parent
  644   renamed

  $ hg convert source-hg hg2hg
  initializing destination hg2hg repository
  scanning source...
  sorting...
  converting...
  5 Initial add
  4 Added branch1 file
  3 Added parent file
  2 Added brach2 file
  1 Merged branches
  0 (octopus merge fixup)

BUG: The manifest entries should be the same for matching revisions, and
nothing should be outgoing

  $ hg -R source-hg manifest --debug -r tip | grep renamed
  67109fdebf6c556eb0a9d5696dd98c8420520405 644   renamed
  $ hg -R hg2hg manifest --debug -r tip | grep renamed
  27c968376d7c3afd095ecb9c7697919b933448c8 644   renamed
  $ hg -R source-hg manifest --debug -r 'tip^' | grep renamed
  27c968376d7c3afd095ecb9c7697919b933448c8 644   renamed
  $ hg -R hg2hg manifest --debug -r 'tip^' | grep renamed
  27c968376d7c3afd095ecb9c7697919b933448c8 644   renamed

BUG: The revisions found should be the same in both repos

  $ hg --cwd source-hg log -r 'file("renamed")' -G -Tcompact
  o    5[tip]:4,3   6652429c300a   2009-10-10 08:00 +0100   foo
  |\     (octopus merge fixup)
  | |
  | o    4:2,1   e0ae8af3503a   2009-10-10 08:00 +0100   foo
  | |\     Merged branches
  | ~ ~
  o  3   138bed2e14be   2009-10-10 08:00 +0100   foo
  |    Added brach2 file
  ~
  $ hg --cwd hg2hg log -r 'file("renamed")' -G -Tcompact
  o    4:2,1   e0ae8af3503a   2009-10-10 08:00 +0100   foo
  |\     Merged branches
  ~ ~
  o  3   138bed2e14be   2009-10-10 08:00 +0100   foo
  |    Added brach2 file
  ~

BUG(?): The move seems to be recorded in rev 4, so it should probably show up
there.  It's not recorded as a move in rev 5, even in source-hg.

  $ hg -R source-hg up -q tip
  $ hg -R hg2hg up -q tip
  $ hg --cwd source-hg log -r 'follow("renamed")' -G -Tcompact
  @    5[tip]:4,3   6652429c300a   2009-10-10 08:00 +0100   foo
  |\     (octopus merge fixup)
  | :
  o :  3   138bed2e14be   2009-10-10 08:00 +0100   foo
  :/     Added brach2 file
  :
  o  0   18b86f5df51b   2009-10-10 08:00 +0100   foo
       Initial add
  
  $ hg --cwd hg2hg log -r 'follow("renamed")' -G -Tcompact
  o  3   138bed2e14be   2009-10-10 08:00 +0100   foo
  :    Added brach2 file
  :
  o  0   18b86f5df51b   2009-10-10 08:00 +0100   foo
       Initial add
  

  $ hg -R hg2hg out source-hg -T compact
  comparing with source-hg
  searching for changes
  5[tip]:4,3   3be2299ccd31   2009-10-10 08:00 +0100   foo
    (octopus merge fixup)
  

  $ glog -R hg2hg
  @    5@source "(octopus merge fixup)" files+: [], files-: [], files: []
  |\
  | o    4@source "Merged branches" files+: [file-branch2 renamed], files-: [rename_me], files: []
  | |\
  o---+  3@source-branch2 "Added brach2 file" files+: [file-branch2 renamed], files-: [rename_me], files: []
   / /
  | o  2@source "Added parent file" files+: [file-parent], files-: [], files: []
  | |
  o |  1@source-branch1 "Added branch1 file" files+: [file-branch1], files-: [], files: [file]
  |/
  o  0@source "Initial add" files+: [file rename_me], files-: [], files: []
  

  $ hg -R source-hg log --debug -r tip
  changeset:   5:6652429c300ab66fdeaf2e730945676a00b53231
  branch:      source
  tag:         tip
  phase:       draft
  parent:      4:e0ae8af3503af9bbffb0b29268a02744cc61a561
  parent:      3:138bed2e14be415a2692b02e41405b2864f758b4
  manifest:    5:1eabd5f5d4b985784cf2c45c717ff053eca14b0d
  user:        Foo Bar <[e-mail]>
  date:        Sat Oct 10 08:00:04 2009 +0100
  files:       renamed
  extra:       branch=source
  description:
  (octopus merge fixup)
  
  
  $ hg -R hg2hg log --debug -r tip
  changeset:   5:3be2299ccd315ff9aab2b49bdb0d14e3244435e8
  branch:      source
  tag:         tip
  phase:       draft
  parent:      4:e0ae8af3503af9bbffb0b29268a02744cc61a561
  parent:      3:138bed2e14be415a2692b02e41405b2864f758b4
  manifest:    4:3ece3c7f2cc6df15b3cbbf3273c69869fc7c3ab0
  user:        Foo Bar <[e-mail]>
  date:        Sat Oct 10 08:00:04 2009 +0100
  extra:       branch=source
  description:
  (octopus merge fixup)
  
  
  $ hg -R source-hg manifest --debug -r tip
  cdf31ed9242b209cd94697112160e2c5b37a667d 644   file
  5108144f585149b29779d7c7e51d61dd22303ffe 644   file-branch1
  80753c4a9ac3806858405b96b24a907b309e3616 644   file-branch2
  7108421418404a937c684d2479a34a24d2ce4757 644   file-parent
  67109fdebf6c556eb0a9d5696dd98c8420520405 644   renamed
  $ hg -R source-hg manifest --debug -r 'tip^'
  cdf31ed9242b209cd94697112160e2c5b37a667d 644   file
  5108144f585149b29779d7c7e51d61dd22303ffe 644   file-branch1
  80753c4a9ac3806858405b96b24a907b309e3616 644   file-branch2
  7108421418404a937c684d2479a34a24d2ce4757 644   file-parent
  27c968376d7c3afd095ecb9c7697919b933448c8 644   renamed

  $ hg -R hg2hg manifest --debug -r tip
  cdf31ed9242b209cd94697112160e2c5b37a667d 644   file
  5108144f585149b29779d7c7e51d61dd22303ffe 644   file-branch1
  80753c4a9ac3806858405b96b24a907b309e3616 644   file-branch2
  7108421418404a937c684d2479a34a24d2ce4757 644   file-parent
  27c968376d7c3afd095ecb9c7697919b933448c8 644   renamed
  $ hg -R hg2hg manifest --debug -r 'tip^'
  cdf31ed9242b209cd94697112160e2c5b37a667d 644   file
  5108144f585149b29779d7c7e51d61dd22303ffe 644   file-branch1
  80753c4a9ac3806858405b96b24a907b309e3616 644   file-branch2
  7108421418404a937c684d2479a34a24d2ce4757 644   file-parent
  27c968376d7c3afd095ecb9c7697919b933448c8 644   renamed

  $ cd ..