view tests/test-mq-qdelete.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

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH

  $ hg init a
  $ cd a

  $ echo 'base' > base
  $ hg ci -Ambase -d '1 0'
  adding base

  $ hg qnew -d '1 0' pa
  $ hg qnew -d '1 0' pb
  $ hg qnew -d '1 0' pc

  $ hg qdel
  abort: qdelete requires at least one revision or patch name
  [255]

  $ hg qdel pc
  abort: cannot delete applied patch pc
  [255]

  $ hg qpop
  popping pc
  now at: pb

Delete the same patch twice in one command (issue2427)

  $ hg qdel pc pc

  $ hg qseries
  pa
  pb

  $ ls .hg/patches
  pa
  pb
  series
  status

  $ hg qpop
  popping pb
  now at: pa

  $ hg qdel -k 1

  $ ls .hg/patches
  pa
  pb
  series
  status

  $ hg qdel -r pa
  patch pa finalized without changeset message

  $ hg qapplied

  $ hg log --template '{rev} {desc}\n'
  1 [mq]: pa
  0 base

  $ hg qnew pd
  $ hg qnew pe
  $ hg qnew pf

  $ hg qdel -r pe
  abort: cannot delete revision 3 above applied patches
  [255]

  $ hg qdel -r qbase:pe
  patch pd finalized without changeset message
  patch pe finalized without changeset message

  $ hg qapplied
  pf

  $ hg log --template '{rev} {desc}\n'
  4 [mq]: pf
  3 [mq]: pe
  2 [mq]: pd
  1 [mq]: pa
  0 base

  $ cd ..

  $ hg init b
  $ cd b

  $ echo 'base' > base
  $ hg ci -Ambase -d '1 0'
  adding base

  $ hg qfinish
  abort: no revisions specified
  [255]

  $ hg qfinish -a
  no patches applied

  $ hg qnew -d '1 0' pa
  $ hg qnew -d '1 0' pb
  $ hg qnew pc # XXX fails to apply by /usr/bin/patch if we put a date

  $ hg qfinish 0
  abort: revision 0 is not managed
  [255]

  $ hg qfinish pb
  abort: cannot delete revision 2 above applied patches
  [255]

  $ hg qpop
  popping pc
  now at: pb

  $ hg qfinish -a pc
  abort: unknown revision 'pc'
  [10]

  $ hg qpush
  applying pc
  patch pc is empty
  now at: pc

  $ hg qfinish qbase:pb
  patch pa finalized without changeset message
  patch pb finalized without changeset message

  $ hg qapplied
  pc

  $ hg log --template '{rev} {desc}\n'
  3 imported patch pc
  2 [mq]: pb
  1 [mq]: pa
  0 base

  $ hg qfinish -a pc
  patch pc finalized without changeset message

  $ hg qapplied

  $ hg log --template '{rev} {desc}\n'
  3 imported patch pc
  2 [mq]: pb
  1 [mq]: pa
  0 base

  $ ls .hg/patches
  series
  status

qdel -k X && hg qimp -e X used to trigger spurious output with versioned queues

  $ hg init --mq
  $ hg qimport -r 3
  $ hg qpop
  popping imported_patch_pc
  patch queue now empty
  $ hg qdel -k imported_patch_pc
  $ hg qimp -e imported_patch_pc
  adding imported_patch_pc to series file
  $ hg qfinish -a
  no patches applied


resilience to inconsistency: qfinish -a with applied patches not in series

  $ hg qser
  imported_patch_pc
  $ hg qapplied
  $ hg qpush
  applying imported_patch_pc
  patch imported_patch_pc is empty
  now at: imported_patch_pc
  $ echo next >>  base
  $ hg qrefresh -d '1 0'
  $ echo > .hg/patches/series # remove 3.diff from series to confuse mq
  $ hg qfinish -a
  revision 47dfa8501675 refers to unknown patches: imported_patch_pc

more complex state 'both known and unknown patches

  $ echo hip >>  base
  $ hg qnew -f -d '1 0' -m 4 4.diff
  $ echo hop >>  base
  $ hg qnew -f -d '1 0' -m 5 5.diff
  $ echo > .hg/patches/series # remove 4.diff and 5.diff from series to confuse mq
  $ echo hup >>  base
  $ hg qnew -f -d '1 0' -m 6 6.diff
  $ echo pup > base
  $ hg qfinish -a
  warning: uncommitted changes in the working directory
  revision 2b1c98802260 refers to unknown patches: 5.diff
  revision 33a6861311c0 refers to unknown patches: 4.diff

  $ cd ..