view tests/test-remotefilelog-push-pull.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 no-windows

  $ . "$TESTDIR/remotefilelog-library.sh"

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > server=True
  > EOF
  $ echo x > x
  $ hg commit -qAm x

  $ cd ..

  $ hgcloneshallow ssh://user@dummy/master shallow -q
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
  $ hgcloneshallow ssh://user@dummy/master shallow2 -q

We should see the remotefilelog capability here, which advertises that
the server supports our custom getfiles method.

  $ cd master
  $ echo 'hello' | hg -R . serve --stdio | grep capa | identifyrflcaps
  exp-remotefilelog-ssh-getfiles-1
  x_rfl_getfile
  x_rfl_getflogheads
  $ echo 'capabilities' | hg -R . serve --stdio | identifyrflcaps ; echo
  exp-remotefilelog-ssh-getfiles-1
  x_rfl_getfile
  x_rfl_getflogheads
  
# pull to shallow from full

  $ echo y > y
  $ hg commit -qAm y

  $ cd ../shallow
  $ hg pull
  pulling from ssh://user@dummy/master
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files
  new changesets d34c38483be9
  (run 'hg update' to get a working copy)

  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)

  $ cat y
  y

  $ cd ..

# pull from shallow to shallow (local)

  $ cd shallow
  $ echo z > z
  $ hg commit -qAm z
  $ echo x >> x
  $ echo y >> y
  $ hg commit -qAm xxyy
  $ cd ../shallow2
  $ clearcache
  $ hg pull ../shallow
  pulling from ../shallow
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 4 changes to 3 files
  new changesets d34c38483be9:d7373980d475 (2 drafts)
  (run 'hg update' to get a working copy)
  2 files fetched over 2 fetches - (2 misses, 0.00% hit ratio) over *s (glob)

# pull from shallow to shallow (ssh)

  $ hg strip -r 1
  saved backup bundle to $TESTTMP/shallow2/.hg/strip-backup/d34c38483be9-89d325c9-backup.hg (glob)
  $ hg pull ssh://user@dummy/$TESTTMP/shallow --config remotefilelog.cachepath=${CACHEDIR}2
  pulling from ssh://user@dummy/$TESTTMP/shallow
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 4 changes to 3 files
  new changesets d34c38483be9:d7373980d475 (2 drafts)
  (run 'hg update' to get a working copy)
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)

  $ hg up
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat z
  z

  $ hg -R ../shallow strip -qr 3
  $ hg strip -qr 3
  $ cd ..

# push from shallow to shallow

  $ cd shallow
  $ echo a > a
  $ hg commit -qAm a
  $ hg push ssh://user@dummy/$TESTTMP/shallow2
  pushing to ssh://user@dummy/$TESTTMP/shallow2
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 1 changes to 1 files

  $ cd ../shallow2
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat a
  a

# verify files are read-only

  $ ls -l .hg/store/data
  total * (glob)
  drwxrwxr-x* 11f6ad8ec52a2984abaafd7c3b516503785c2072 (glob)
  drwxrwxr-x* 395df8f7c51f007019cb30201c49e884b46b92fa (glob)
  drwxrwxr-x* 86f7e437faa5a7fce15d1ddcb9eaeaea377667b8 (glob)
  drwxrwxr-x* 95cb0bfd2977c761298d9624e4b4d4c72a39974a (glob)
  $ ls -l .hg/store/data/395df8f7c51f007019cb30201c49e884b46b92fa
  total * (glob)
  -r--r--r--* 69a1b67522704ec122181c0890bd16e9d3e7516a (glob)
  -r--r--r--* 69a1b67522704ec122181c0890bd16e9d3e7516a_old (glob)
  $ cd ..

# push from shallow to full

  $ cd shallow
  $ hg push
  pushing to ssh://user@dummy/master
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 2 changesets with 2 changes to 2 files

  $ cd ../master
  $ hg log -l 1 --style compact
  3[tip]   1489bbbc46f0   1970-01-01 00:00 +0000   test
    a
  
  $ hg up
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat a
  a

# push public commits

  $ cd ../shallow
  $ echo p > p
  $ hg commit -qAm p
  $ hg phase -f -p -r .
  $ echo d > d
  $ hg commit -qAm d

  $ cd ../shallow2
  $ hg pull ../shallow
  pulling from ../shallow
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets 3a2e32c04641:cedeb4167c1f (1 drafts)
  2 local changesets published (?)
  (run 'hg update' to get a working copy)

  $ cd ..

# Test pushing from shallow to shallow with multiple manifests introducing the
# same filenode. Test this by constructing two separate histories of file 'c'
# that share a file node and verifying that the history works after pushing.

  $ hg init multimf-master
  $ hgcloneshallow ssh://user@dummy/multimf-master multimf-shallow -q
  $ hgcloneshallow ssh://user@dummy/multimf-master multimf-shallow2 -q
  $ cd multimf-shallow
  $ echo a > a
  $ hg commit -qAm a
  $ echo b > b
  $ hg commit -qAm b
  $ echo c > c
  $ hg commit -qAm c1
  $ hg up -q 0
  $ echo c > c
  $ hg commit -qAm c2
  $ echo cc > c
  $ hg commit -qAm c22
  $ hg log -G -T '{rev} {desc}\n'
  @  4 c22
  |
  o  3 c2
  |
  | o  2 c1
  | |
  | o  1 b
  |/
  o  0 a
  

  $ cd ../multimf-shallow2
- initial commit to prevent hg pull from being a clone
  $ echo z > z && hg commit -qAm z
  $ hg pull -f ssh://user@dummy/$TESTTMP/multimf-shallow
  pulling from ssh://user@dummy/$TESTTMP/multimf-shallow
  searching for changes
  warning: repository is unrelated
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 5 changesets with 4 changes to 3 files (+2 heads)
  new changesets cb9a9f314b8b:d8f06a4c6d38 (5 drafts)
  (run 'hg heads' to see heads, 'hg merge' to merge)

  $ hg up -q 5
  $ hg log -f -T '{rev}\n' c
  5
  4