view tests/test-encoding.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 character encoding

  $ hg init t
  $ cd t

we need a repo with some legacy latin-1 changesets

  $ hg unbundle "$TESTDIR/bundles/legacy-encoding.hg"
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 1 files
  new changesets 1e78a93102a3:0e5b7e3f9c4a (2 drafts)
  (run 'hg update' to get a working copy)
  $ hg co
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ "$PYTHON" << EOF
  > f = open('latin-1', 'wb'); f.write(b"latin-1 e' encoded: \xe9"); f.close()
  > f = open('utf-8', 'wb'); f.write(b"utf-8 e' encoded: \xc3\xa9"); f.close()
  > f = open('latin-1-tag', 'wb'); f.write(b"\xe9"); f.close()
  > EOF

should fail with encoding error

  $ echo "plain old ascii" > a
  $ hg st
  M a
  ? latin-1
  ? latin-1-tag
  ? utf-8
  $ HGENCODING=ascii hg ci -l latin-1
  transaction abort!
  rollback completed
  abort: decoding near ' encoded: \xe9': 'ascii' codec can't decode byte 0xe9 in position 20: ordinal not in range(128)! (esc)
  [255]

these should work

  $ echo "latin-1" > a
  $ HGENCODING=latin-1 hg ci -l latin-1
  $ echo "utf-8" > a
  $ HGENCODING=utf-8 hg ci -l utf-8
  $ HGENCODING=latin-1 hg tag `cat latin-1-tag`
  $ HGENCODING=latin-1 hg branch `cat latin-1-tag`
  marked working directory as branch \xe9 (esc)
  (branches are permanent and global, did you want a bookmark?)
  $ HGENCODING=latin-1 hg ci -m 'latin1 branch'
  $ hg -q rollback
  $ HGENCODING=latin-1 hg branch
  \xe9 (esc)
  $ HGENCODING=latin-1 hg ci -m 'latin1 branch'
  $ rm .hg/branch

hg log (ascii)

  $ hg --encoding ascii log
  changeset:   5:a52c0692f24a
  branch:      ?
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin1 branch
  
  changeset:   4:94db611b4196
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag ? for changeset ca661e7520de
  
  changeset:   3:ca661e7520de
  tag:         ?
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     utf-8 e' encoded: ?
  
  changeset:   2:650c6f3d55dd
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin-1 e' encoded: ?
  
  changeset:   1:0e5b7e3f9c4a
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     koi8-r: ????? = u'\u0440\u0442\u0443\u0442\u044c'
  
  changeset:   0:1e78a93102a3
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     latin-1 e': ? = u'\xe9'
  

hg log (latin-1)

  $ hg --encoding latin-1 log
  changeset:   5:a52c0692f24a
  branch:      \xe9 (esc)
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin1 branch
  
  changeset:   4:94db611b4196
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag \xe9 for changeset ca661e7520de (esc)
  
  changeset:   3:ca661e7520de
  tag:         \xe9 (esc)
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     utf-8 e' encoded: \xe9 (esc)
  
  changeset:   2:650c6f3d55dd
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin-1 e' encoded: \xe9 (esc)
  
  changeset:   1:0e5b7e3f9c4a
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     koi8-r: \xd2\xd4\xd5\xd4\xd8 = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc)
  
  changeset:   0:1e78a93102a3
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     latin-1 e': \xe9 = u'\\xe9' (esc)
  

hg log (utf-8)

  $ hg --encoding utf-8 log
  changeset:   5:a52c0692f24a
  branch:      \xc3\xa9 (esc)
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin1 branch
  
  changeset:   4:94db611b4196
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag \xc3\xa9 for changeset ca661e7520de (esc)
  
  changeset:   3:ca661e7520de
  tag:         \xc3\xa9 (esc)
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     utf-8 e' encoded: \xc3\xa9 (esc)
  
  changeset:   2:650c6f3d55dd
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin-1 e' encoded: \xc3\xa9 (esc)
  
  changeset:   1:0e5b7e3f9c4a
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     koi8-r: \xc3\x92\xc3\x94\xc3\x95\xc3\x94\xc3\x98 = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc)
  
  changeset:   0:1e78a93102a3
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     latin-1 e': \xc3\xa9 = u'\\xe9' (esc)
  

hg tags (ascii)

  $ HGENCODING=ascii hg tags
  tip                                5:a52c0692f24a
  ?                                  3:ca661e7520de

hg tags (latin-1)

  $ HGENCODING=latin-1 hg tags
  tip                                5:a52c0692f24a
  \xe9                                  3:ca661e7520de (esc)

hg tags (utf-8)

  $ HGENCODING=utf-8 hg tags
  tip                                5:a52c0692f24a
  \xc3\xa9                                  3:ca661e7520de (esc)

hg tags (JSON)

  $ hg tags -Tjson
  [
   {
    "node": "a52c0692f24ad921c0a31e1736e7635a8b23b670",
    "rev": 5,
    "tag": "tip",
    "type": ""
   },
   {
    "node": "ca661e7520dec3f5438a63590c350bebadb04989",
    "rev": 3,
    "tag": "\xc3\xa9", (esc)
    "type": ""
   }
  ]

hg branches (ascii)

  $ HGENCODING=ascii hg branches
  ?                              5:a52c0692f24a
  default                        4:94db611b4196 (inactive)

hg branches (latin-1)

  $ HGENCODING=latin-1 hg branches
  \xe9                              5:a52c0692f24a (esc)
  default                        4:94db611b4196 (inactive)

hg branches (utf-8)

  $ HGENCODING=utf-8 hg branches
  \xc3\xa9                              5:a52c0692f24a (esc)
  default                        4:94db611b4196 (inactive)
  $ echo '[ui]' >> .hg/hgrc
  $ echo 'fallbackencoding = koi8-r' >> .hg/hgrc

hg log (utf-8)

  $ HGENCODING=utf-8 hg log
  changeset:   5:a52c0692f24a
  branch:      \xc3\xa9 (esc)
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin1 branch
  
  changeset:   4:94db611b4196
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag \xc3\xa9 for changeset ca661e7520de (esc)
  
  changeset:   3:ca661e7520de
  tag:         \xc3\xa9 (esc)
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     utf-8 e' encoded: \xc3\xa9 (esc)
  
  changeset:   2:650c6f3d55dd
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin-1 e' encoded: \xc3\xa9 (esc)
  
  changeset:   1:0e5b7e3f9c4a
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     koi8-r: \xd1\x80\xd1\x82\xd1\x83\xd1\x82\xd1\x8c = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc)
  
  changeset:   0:1e78a93102a3
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     latin-1 e': \xd0\x98 = u'\\xe9' (esc)
  

hg log (dolphin)

  $ HGENCODING=dolphin hg log
  abort: unknown encoding: dolphin
  (please check your locale settings)
  [255]
  $ HGENCODING=ascii hg branch `cat latin-1-tag`
  abort: decoding near '\xe9': 'ascii' codec can't decode byte 0xe9 in position 0: ordinal not in range(128)! (esc)
  [255]
  $ cp latin-1-tag .hg/branch
  $ HGENCODING=latin-1 hg ci -m 'auto-promote legacy name'

Test roundtrip encoding of lookup tables when not using UTF-8 (issue2763)

  $ HGENCODING=latin-1 hg up `cat latin-1-tag`
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ cd ..

Test roundtrip encoding/decoding of utf8b for generated data

#if hypothesis

  >>> import hypothesishelpers
  >>> from mercurial import encoding
  >>> hypothesishelpers.roundtrips(hypothesishelpers.st.binary(),
  ...                              encoding.fromutf8b, encoding.toutf8b)
  Round trip OK

#endif