view tests/test-fileset-generated.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

  $ hg init

Set up history and working copy

  $ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 1
  $ hg addremove -q --similarity 0
  $ hg commit -m first

  $ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 2
  $ hg addremove -q --similarity 0
  $ hg commit -m second

  $ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 wc
  $ hg addremove -q --similarity 0
  $ hg forget *_*_*-untracked
  $ rm *_*_missing-*

Test status

  $ hg st -A 'set:modified()'
  M content1_content1_content3-tracked
  M content1_content2_content1-tracked
  M content1_content2_content3-tracked
  M missing_content2_content3-tracked

  $ hg st -A 'set:added()'
  A content1_missing_content1-tracked
  A content1_missing_content3-tracked
  A missing_missing_content3-tracked

  $ hg st -A 'set:removed()'
  R content1_content1_content1-untracked
  R content1_content1_content3-untracked
  R content1_content1_missing-untracked
  R content1_content2_content1-untracked
  R content1_content2_content2-untracked
  R content1_content2_content3-untracked
  R content1_content2_missing-untracked
  R missing_content2_content2-untracked
  R missing_content2_content3-untracked
  R missing_content2_missing-untracked

  $ hg st -A 'set:deleted()'
  ! content1_content1_missing-tracked
  ! content1_content2_missing-tracked
  ! content1_missing_missing-tracked
  ! missing_content2_missing-tracked
  ! missing_missing_missing-tracked

  $ hg st -A 'set:missing()'
  ! content1_content1_missing-tracked
  ! content1_content2_missing-tracked
  ! content1_missing_missing-tracked
  ! missing_content2_missing-tracked
  ! missing_missing_missing-tracked

  $ hg st -A 'set:unknown()'
  ? content1_missing_content1-untracked
  ? content1_missing_content3-untracked
  ? missing_missing_content3-untracked

  $ hg st -A 'set:clean()'
  C content1_content1_content1-tracked
  C content1_content2_content2-tracked
  C missing_content2_content2-tracked

Test log

  $ hg log -T '{rev}\n' --stat 'set:modified()'
  1
   content1_content2_content1-tracked |  2 +-
   content1_content2_content3-tracked |  2 +-
   missing_content2_content3-tracked  |  1 +
   3 files changed, 3 insertions(+), 2 deletions(-)
  
  0
   content1_content1_content3-tracked |  1 +
   content1_content2_content1-tracked |  1 +
   content1_content2_content3-tracked |  1 +
   3 files changed, 3 insertions(+), 0 deletions(-)
  
Largefiles doesn't crash
  $ hg log -T '{rev}\n' --stat 'set:modified()' --config extensions.largefiles=
  The fsmonitor extension is incompatible with the largefiles extension and has been disabled. (fsmonitor !)
  1
   content1_content2_content1-tracked |  2 +-
   content1_content2_content3-tracked |  2 +-
   missing_content2_content3-tracked  |  1 +
   3 files changed, 3 insertions(+), 2 deletions(-)
  
  0
   content1_content1_content3-tracked |  1 +
   content1_content2_content1-tracked |  1 +
   content1_content2_content3-tracked |  1 +
   3 files changed, 3 insertions(+), 0 deletions(-)
  
  $ hg log -T '{rev}\n' --stat 'set:added()'
  1
   content1_missing_content1-tracked |  1 -
   content1_missing_content3-tracked |  1 -
   2 files changed, 0 insertions(+), 2 deletions(-)
  
  0
   content1_missing_content1-tracked |  1 +
   content1_missing_content3-tracked |  1 +
   2 files changed, 2 insertions(+), 0 deletions(-)
  
  $ hg log -T '{rev}\n' --stat 'set:removed()'
  1
   content1_content2_content1-untracked |  2 +-
   content1_content2_content2-untracked |  2 +-
   content1_content2_content3-untracked |  2 +-
   content1_content2_missing-untracked  |  2 +-
   missing_content2_content2-untracked  |  1 +
   missing_content2_content3-untracked  |  1 +
   missing_content2_missing-untracked   |  1 +
   7 files changed, 7 insertions(+), 4 deletions(-)
  
  0
   content1_content1_content1-untracked |  1 +
   content1_content1_content3-untracked |  1 +
   content1_content1_missing-untracked  |  1 +
   content1_content2_content1-untracked |  1 +
   content1_content2_content2-untracked |  1 +
   content1_content2_content3-untracked |  1 +
   content1_content2_missing-untracked  |  1 +
   7 files changed, 7 insertions(+), 0 deletions(-)
  
  $ hg log -T '{rev}\n' --stat 'set:deleted()'
  1
   content1_content2_missing-tracked |  2 +-
   content1_missing_missing-tracked  |  1 -
   missing_content2_missing-tracked  |  1 +
   3 files changed, 2 insertions(+), 2 deletions(-)
  
  0
   content1_content1_missing-tracked |  1 +
   content1_content2_missing-tracked |  1 +
   content1_missing_missing-tracked  |  1 +
   3 files changed, 3 insertions(+), 0 deletions(-)
  
  $ hg log -T '{rev}\n' --stat 'set:unknown()'
  1
   content1_missing_content1-untracked |  1 -
   content1_missing_content3-untracked |  1 -
   2 files changed, 0 insertions(+), 2 deletions(-)
  
  0
   content1_missing_content1-untracked |  1 +
   content1_missing_content3-untracked |  1 +
   2 files changed, 2 insertions(+), 0 deletions(-)
  
  $ hg log -T '{rev}\n' --stat 'set:clean()'
  1
   content1_content2_content2-tracked |  2 +-
   missing_content2_content2-tracked  |  1 +
   2 files changed, 2 insertions(+), 1 deletions(-)
  
  0
   content1_content1_content1-tracked |  1 +
   content1_content2_content2-tracked |  1 +
   2 files changed, 2 insertions(+), 0 deletions(-)
  
Test revert

  $ hg revert 'set:modified()'
  reverting content1_content1_content3-tracked
  reverting content1_content2_content1-tracked
  reverting content1_content2_content3-tracked
  reverting missing_content2_content3-tracked

  $ hg revert 'set:added()'
  forgetting content1_missing_content1-tracked
  forgetting content1_missing_content3-tracked
  forgetting missing_missing_content3-tracked

  $ hg revert 'set:removed()'
  undeleting content1_content1_content1-untracked
  undeleting content1_content1_content3-untracked
  undeleting content1_content1_missing-untracked
  undeleting content1_content2_content1-untracked
  undeleting content1_content2_content2-untracked
  undeleting content1_content2_content3-untracked
  undeleting content1_content2_missing-untracked
  undeleting missing_content2_content2-untracked
  undeleting missing_content2_content3-untracked
  undeleting missing_content2_missing-untracked

  $ hg revert 'set:deleted()'
  forgetting content1_missing_missing-tracked
  forgetting missing_missing_missing-tracked
  reverting content1_content1_missing-tracked
  reverting content1_content2_missing-tracked
  reverting missing_content2_missing-tracked

  $ hg revert 'set:unknown()'

  $ hg revert 'set:clean()'