view tests/test-sparse-profiles.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

test sparse

  $ hg init myrepo
  $ cd myrepo
  $ cat > .hg/hgrc <<EOF
  > [extensions]
  > sparse=
  > purge=
  > strip=
  > rebase=
  > EOF

Config file without [section] is rejected

  $ cat > bad.sparse <<EOF
  > *.html
  > EOF

  $ hg debugsparse --import-rules bad.sparse
  abort: sparse config entry outside of section: *.html
  (add an [include] or [exclude] line to declare the entry type)
  [255]
  $ rm bad.sparse

  $ echo a > index.html
  $ echo x > data.py
  $ echo z > readme.txt
  $ cat > webpage.sparse <<EOF
  > # frontend sparse profile
  > [include]
  > *.html
  > EOF
  $ cat > backend.sparse <<EOF
  > # backend sparse profile
  > [include]
  > *.py
  > EOF
  $ hg ci -Aqm 'initial'

  $ hg debugsparse --include '*.sparse'

Verify enabling a single profile works

  $ hg debugsparse --enable-profile webpage.sparse
  $ ls -A
  .hg
  backend.sparse
  index.html
  webpage.sparse

Verify enabling two profiles works

  $ hg debugsparse --enable-profile backend.sparse
  $ ls -A
  .hg
  backend.sparse
  data.py
  index.html
  webpage.sparse

Verify disabling a profile works

  $ hg debugsparse --disable-profile webpage.sparse
  $ ls -A
  .hg
  backend.sparse
  data.py
  webpage.sparse

Verify that a profile is updated across multiple commits

  $ cat > webpage.sparse <<EOF
  > # frontend sparse profile
  > [include]
  > *.html
  > EOF
  $ cat > backend.sparse <<EOF
  > # backend sparse profile
  > [include]
  > *.py
  > *.txt
  > EOF

  $ echo foo >> data.py

  $ hg ci -m 'edit profile'
  $ ls -A
  .hg
  backend.sparse
  data.py
  readme.txt
  webpage.sparse

  $ hg up -q 0
  $ ls -A
  .hg
  backend.sparse
  data.py
  webpage.sparse

  $ hg up -q 1
  $ ls -A
  .hg
  backend.sparse
  data.py
  readme.txt
  webpage.sparse

Introduce a conflicting .hgsparse change

  $ hg up -q 0
  $ cat > backend.sparse <<EOF
  > # Different backend sparse profile
  > [include]
  > *.html
  > EOF
  $ echo bar >> data.py

  $ hg ci -qAm "edit profile other"
  $ ls -A
  .hg
  backend.sparse
  index.html
  webpage.sparse

Verify conflicting merge pulls in the conflicting changes

  $ hg merge 1
  temporarily included 2 file(s) in the sparse checkout for merging
  merging backend.sparse
  warning: conflicts while merging backend.sparse! (edit, then use 'hg resolve --mark')
  merging data.py
  warning: conflicts while merging data.py! (edit, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 2 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
  [1]

  $ rm *.orig
  $ ls -A
  .hg
  backend.sparse
  data.py
  index.html
  webpage.sparse

Verify resolving the merge removes the temporarily unioned files

  $ cat > backend.sparse <<EOF
  > # backend sparse profile
  > [include]
  > *.html
  > *.txt
  > EOF
  $ hg resolve -m backend.sparse

  $ cat > data.py <<EOF
  > x
  > foo
  > bar
  > EOF
  $ hg resolve -m data.py
  (no more unresolved files)

  $ hg ci -qAm "merge profiles"
  $ ls -A
  .hg
  backend.sparse
  index.html
  readme.txt
  webpage.sparse

  $ hg cat -r . data.py
  x
  foo
  bar

Verify stripping refreshes dirstate

  $ hg strip -q -r .
  $ ls -A
  .hg
  backend.sparse
  index.html
  webpage.sparse

Verify rebase conflicts pulls in the conflicting changes

  $ hg up -q 1
  $ ls -A
  .hg
  backend.sparse
  data.py
  readme.txt
  webpage.sparse

  $ hg rebase -d 2
  rebasing 1:a2b1de640a62 "edit profile"
  temporarily included 2 file(s) in the sparse checkout for merging
  merging backend.sparse
  warning: conflicts while merging backend.sparse! (edit, then use 'hg resolve --mark')
  merging data.py
  warning: conflicts while merging data.py! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]
  $ rm *.orig
  $ ls -A
  .hg
  backend.sparse
  data.py
  index.html
  webpage.sparse

Verify resolving conflict removes the temporary files

  $ cat > backend.sparse <<EOF
  > [include]
  > *.html
  > *.txt
  > EOF
  $ hg resolve -m backend.sparse

  $ cat > data.py <<EOF
  > x
  > foo
  > bar
  > EOF
  $ hg resolve -m data.py
  (no more unresolved files)
  continue: hg rebase --continue

  $ hg rebase -q --continue
  $ ls -A
  .hg
  backend.sparse
  index.html
  readme.txt
  webpage.sparse

  $ hg cat -r . data.py
  x
  foo
  bar

Test checking out a commit that does not contain the sparse profile. The
warning message can be suppressed by setting missingwarning = false in
[sparse] section of your config:

  $ hg debugsparse --reset
  $ hg rm *.sparse
  $ hg commit -m "delete profiles"
  $ hg up -q ".^"
  $ hg debugsparse --enable-profile backend.sparse
  $ ls -A
  .hg
  index.html
  readme.txt
  $ hg up tip | grep warning
  warning: sparse profile 'backend.sparse' not found in rev bfcb76de99cc - ignoring it
  [1]
  $ ls -A
  .hg
  data.py
  index.html
  readme.txt
  $ hg debugsparse --disable-profile backend.sparse | grep warning
  warning: sparse profile 'backend.sparse' not found in rev bfcb76de99cc - ignoring it
  [1]
  $ cat >> .hg/hgrc <<EOF
  > [sparse]
  > missingwarning = false
  > EOF
  $ hg debugsparse --enable-profile backend.sparse

  $ cd ..

#if unix-permissions

Test file permissions changing across a sparse profile change
  $ hg init sparseperm
  $ cd sparseperm
  $ cat > .hg/hgrc <<EOF
  > [extensions]
  > sparse=
  > EOF
  $ touch a b
  $ cat > .hgsparse <<EOF
  > [include]
  > a
  > EOF
  $ hg commit -Aqm 'initial'
  $ chmod a+x b
  $ hg commit -qm 'make executable'
  $ cat >> .hgsparse <<EOF
  > b
  > EOF
  $ hg commit -qm 'update profile'
  $ hg up -q 0
  $ hg debugsparse --enable-profile .hgsparse
  $ hg up -q 2
  $ ls -l b
  -rwxr-xr-x* b (glob)

#endif