view tests/test-bookflow.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

initialize
  $ make_changes() {
  >     d=`pwd`
  >     [ ! -z $1 ] && cd $1
  >     echo "test `basename \`pwd\``" >> test
  >     hg commit -Am"${2:-test}"
  >     r=$?
  >     cd $d
  >     return $r
  > }
  $ ls -1a
  .
  ..
  $ hg init a
  $ cd a
  $ echo 'test' > test; hg commit -Am'test'
  adding test

clone to b

  $ mkdir ../b
  $ cd ../b
  $ hg clone ../a .
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo "[extensions]" >> .hg/hgrc
  $ echo "bookflow=" >> .hg/hgrc
  $ hg branch X
  abort: creating named branches is disabled and you should use bookmarks
  (see 'hg help bookflow')
  [255]
  $ hg bookmark X
  $ hg bookmarks
  * X                         0:* (glob)
  $ hg bookmark X
  abort: bookmark X already exists, to move use the --rev option
  [255]
  $ make_changes
  $ hg push ../a -q

  $ hg bookmarks
   \* X                         1:* (glob)

change a
  $ cd ../a
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo 'test' >> test; hg commit -Am'test'


pull in b
  $ cd ../b
  $ hg pull -u
  pulling from $TESTTMP/a
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets * (glob)
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (leaving bookmark X)
  $ hg status
  $ hg bookmarks
     X                         1:* (glob)

check protection of @ bookmark
  $ hg bookmark @
  $ hg bookmarks
   \* @                         2:* (glob)
     X                         1:* (glob)
  $ make_changes
  abort: cannot commit, bookmark @ is protected
  [255]

  $ hg status
  M test
  $ hg bookmarks
   \* @                         2:* (glob)
     X                         1:* (glob)

  $ hg --config bookflow.protect= commit  -Am"Updated test"

  $ hg bookmarks
   \* @                         3:* (glob)
     X                         1:* (glob)

check requirement for an active bookmark
  $ hg bookmark -i
  $ hg bookmarks
     @                         3:* (glob)
     X                         1:* (glob)
  $ make_changes
  abort: cannot commit without an active bookmark
  [255]
  $ hg revert test
  $ rm test.orig
  $ hg status


make the bookmark move by updating it on a, and then pulling
# add a commit to a
  $ cd ../a
  $ hg bookmark X
  $ hg bookmarks
   \* X                         2:* (glob)
  $ make_changes
  $ hg bookmarks
   * X                         3:81af7977fdb9

# go back to b, and check out X
  $ cd ../b
  $ hg up X
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark X)
  $ hg bookmarks
     @                         3:* (glob)
   \* X                         1:* (glob)

# pull, this should move the bookmark forward, because it was changed remotely
  $ hg pull -u | grep "updating to active bookmark X"
  updating to active bookmark X

  $ hg bookmarks
     @                         3:* (glob)
   * X                         4:81af7977fdb9

the bookmark should not move if it diverged from remote
  $ hg -R ../a status
  $ hg -R ../b status
  $ make_changes ../a
  $ make_changes ../b
  $ hg -R ../a status
  $ hg -R ../b status
  $ hg -R ../a bookmarks
   * X                         4:238292f60a57
  $ hg -R ../b bookmarks
     @                         3:* (glob)
   * X                         5:096f7e86892d
  $ cd ../b
  $ # make sure we cannot push after bookmarks diverged
  $ hg push -B X | grep abort
  abort: push creates new remote head * with bookmark 'X' (glob)
  (pull and merge or see 'hg help push' for details about pushing new heads)
  [1]
  $ hg pull -u | grep divergent
  divergent bookmark X stored as X@default
  1 other divergent bookmarks for "X"
  $ hg bookmarks
     @                         3:* (glob)
   * X                         5:096f7e86892d
     X@default                 6:238292f60a57
  $ hg id -in
  096f7e86892d 5
  $ make_changes
  $ hg status
  $ hg bookmarks
     @                         3:* (glob)
   * X                         7:227f941aeb07
     X@default                 6:238292f60a57

now merge with the remote bookmark
  $ hg merge X@default --tool :local -q
  $ hg status
  M test
  $ hg commit -m"Merged with X@default"
  $ hg bookmarks
     @                         3:* (glob)
   * X                         8:26fed9bb3219
  $ hg push -B X | grep bookmark
  pushing to $TESTTMP/a (?)
  updating bookmark X
  $ cd ../a
  $ hg up -q
  $ hg bookmarks
   * X                         7:26fed9bb3219

test hg pull when there is more than one descendant
  $ cd ../a
  $ hg bookmark Z
  $ hg bookmark Y
  $ make_changes . YY
  $ hg up Z -q
  $ make_changes . ZZ
  created new head
  $ hg bookmarks
     X                         7:26fed9bb3219
     Y                         8:131e663dbd2a
   * Z                         9:b74a4149df25
  $ hg log -r 'p1(Y)' -r 'p1(Z)' -T '{rev}\n' # prove that Y and Z share the same parent
  7
  $ hg log -r 'Y%Z' -T '{rev}\n'  # revs in Y but not in Z
  8
  $ hg log -r 'Z%Y' -T '{rev}\n'  # revs in Z but not in Y
  9
  $ cd ../b
  $ hg pull -uq
  $ hg id
  b74a4149df25 tip Z
  $ hg bookmarks | grep \*  # no active bookmark
  [1]


test shelving
  $ cd ../a
  $ echo anotherfile > anotherfile # this change should not conflict
  $ hg add anotherfile
  $ hg commit -m"Change in a"
  $ cd ../b
  $ hg up Z | grep Z
  (activating bookmark Z)
  $ hg book | grep \* # make sure active bookmark
   \* Z                         10:* (glob)
  $ echo "test b" >> test
  $ hg diff --stat
   test |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)
  $ hg shelve
  shelved as Z
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg pull -uq
  $ hg unshelve
  unshelving change 'Z'
  rebasing shelved changes
  $ hg diff --stat
   test |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)


make the bookmark move by updating it on a, and then pulling with a local change
# add a commit to a
  $ cd ../a
  $ hg up -C X |fgrep  "activating bookmark X"
  (activating bookmark X)
# go back to b, and check out X
  $ cd ../b
  $ hg up -C X |fgrep  "activating bookmark X"
  (activating bookmark X)
# update and push from a
  $ make_changes ../a
  created new head
  $ echo "more" >> test
  $ hg pull -u 2>&1 | fgrep -v TESTTMP| fgrep -v "searching for changes" | fgrep -v adding
  pulling from $TESTTMP/a
  updating bookmark X
  added 1 changesets with 0 changes to 0 files (+1 heads)
  new changesets * (glob)
  updating to active bookmark X
  merging test
  warning: conflicts while merging test! (edit, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges
  $ hg update -Cq
  $ rm test.orig

make sure that commits aren't possible if working directory is not pointing to active bookmark
  $ hg -R ../a status
  $ hg -R ../b status
  $ hg -R ../a id -i
  36a6e592ec06
  $ hg -R ../a book | grep X
   \* X                         \d+:36a6e592ec06 (re)
  $ hg -R ../b id -i
  36a6e592ec06
  $ hg -R ../b book | grep X
   \* X                         \d+:36a6e592ec06 (re)
  $ make_changes ../a
  $ hg -R ../a book | grep X
   \* X                         \d+:f73a71c992b8 (re)
  $ cd ../b
  $ hg pull  2>&1 | grep -v add | grep -v pulling | grep -v searching | grep -v changeset
  updating bookmark X
  (run 'hg update' to get a working copy)
  working directory out of sync with active bookmark, run 'hg up X'
  $ hg id -i # we're still on the old commit
  36a6e592ec06
  $ hg book | grep X # while the bookmark moved
   \* X                         \d+:f73a71c992b8 (re)
  $ make_changes
  abort: cannot commit, working directory out of sync with active bookmark
  (run 'hg up X')
  [255]
  $ hg up -Cq -r .  # cleanup local changes
  $ hg status
  $ hg id -i # we're still on the old commit
  36a6e592ec06
  $ hg up X -q
  $ hg id -i # now we're on X
  f73a71c992b8
  $ hg book | grep X
   \* X                         \d+:f73a71c992b8 (re)