tests/test-issue660.t

worker: avoid potential partial write of pickled data

Previously, the code wrote the pickled data using os.write(). However,
os.write() can write less bytes than passed to it. To trigger the problem, the
pickled data had to be larger than 2147479552 bytes on my system.

Instead, open a file object and pass it to pickle.dump(). This also has the
advantage that it doesn’t buffer the whole pickled data in memory.

Note that the opened file must be buffered because pickle doesn’t support
unbuffered streams because unbuffered streams’ write() method might write less
bytes than passed to it (like os.write()) but pickle.dump() relies on that all
bytes are written (see https://github.com/python/cpython/issues/93050).

The side effect of using a file object and a with statement is that wfd is
explicitly closed now while it seems like before it was implicitly closed by
process exit.

#testcases dirstate-v1 dirstate-v2

#if dirstate-v2
  $ cat >> $HGRCPATH << EOF
  > [format]
  > use-dirstate-v2=1
  > [storage]
  > dirstate-v2.slow-path=allow
  > EOF
#endif

https://bz.mercurial-scm.org/660 and:
https://bz.mercurial-scm.org/322

  $ hg init repo
  $ cd repo
  $ echo a > a
  $ mkdir b
  $ echo b > b/b
  $ hg commit -A -m "a is file, b is dir"
  adding a
  adding b/b

File replaced with directory:

  $ rm a
  $ mkdir a
  $ echo a > a/a

Should fail - would corrupt dirstate:

  $ hg add a/a
  abort: file 'a' in dirstate clashes with 'a/a'
  [255]

Removing shadow:

  $ hg rm --after a

Should succeed - shadow removed:

  $ hg add a/a

Directory replaced with file:

  $ rm -r b
  $ echo b > b

Should fail - would corrupt dirstate:

  $ hg add b
  abort: directory 'b' already in dirstate
  [255]

Removing shadow:

  $ hg rm --after b/b

Should succeed - shadow removed:

  $ hg add b

Look what we got:

  $ hg st
  A a/a
  A b
  R a
  R b/b

Revert reintroducing shadow - should fail:

  $ rm -r a b
  $ hg revert b/b
  abort: file 'b' in dirstate clashes with 'b/b'
  [255]

Revert all - should succeed:

  $ hg revert --all
  forgetting a/a
  forgetting b
  undeleting a
  undeleting b/b

  $ hg st

Issue3423:

  $ hg forget a
  $ echo zed > a
  $ hg revert a
  $ hg st
  ? a.orig
  $ rm a.orig

addremove:

  $ rm -r a b
  $ mkdir a
  $ echo a > a/a
  $ echo b > b

  $ hg addremove -s 0
  removing a
  adding a/a
  adding b
  removing b/b

  $ hg st
  A a/a
  A b
  R a
  R b/b

commit:

  $ hg ci -A -m "a is dir, b is file"
  $ hg st --all
  C a/a
  C b

Long directory replaced with file:

  $ mkdir d
  $ mkdir d/d
  $ echo d > d/d/d
  $ hg commit -A -m "d is long directory"
  adding d/d/d

  $ rm -r d
  $ echo d > d

Should fail - would corrupt dirstate:

  $ hg add d
  abort: directory 'd' already in dirstate
  [255]

Removing shadow:

  $ hg rm --after d/d/d

Should succeed - shadow removed:

  $ hg add d
  $ hg ci -md

Update should work at least with clean working directory:

  $ rm -r a b d
  $ hg up -r 0
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg st --all
  C a
  C b/b

  $ rm -r a b
  $ hg up -r 1
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg st --all
  C a/a
  C b