view tests/test-share.t @ 14007:d764463b433e

atomictempfile: avoid infinite recursion in __del__().

The problem is that a programmer using atomictempfile directly can
make an innocent everyday mistake -- not enough args to the
constructor -- which escalates badly.  You would expect a simple
TypeError crash in that case, but you actually get an infinite
recursion that is surprisingly difficult to kill: it happens between
__del__() and __getattr__(), and Python does not handle infinite
recursion from __del__() well.

The fix is to not implement __getattr__(), but instead assign instance
attributes for the methods we wish to delegate to the builtin file
type: write() and fileno(). I've audited mercurial.* and hgext.* and
found no users of atomictempfile using methods other than write() and
rename(). I audited third-party extensions and found one (snap)
passing an atomictempfile to util.fstat(), so I also threw in
fileno().

The last time I submitted a similar patch, Matt proposed that we make
atomictempfile a subclass of file instead of wrapping it. Rejected on
grounds of unnecessary complexity: for one thing, it would make the
Windows implementation of posixfile quite a bit more complex. It would
have to become a subclass of file rather than a simple function -- but
since it's written in C, this is non-obvious and non-trivial.
Furthermore, there's nothing wrong with wrapping objects and
delegating methods: it's a well-established pattern that works just
fine in many cases. Subclassing is not the answer to all of life's
problems.

  $ echo "[extensions]"      >> $HGRCPATH
  $ echo "share = "          >> $HGRCPATH

prepare repo1

  $ hg init repo1
  $ cd repo1
  $ echo a > a
  $ hg commit -A -m'init'
  adding a

share it

  $ cd ..
  $ hg share repo1 repo2
  updating working directory
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

share shouldn't have a store dir

  $ cd repo2
  $ test -d .hg/store
  [1]

Some sed versions appends newline, some don't, and some just fails

  $ cat .hg/sharedpath; echo
  $TESTTMP/repo1/.hg

commit in shared clone

  $ echo a >> a
  $ hg commit -m'change in shared clone'

check original

  $ cd ../repo1
  $ hg log
  changeset:   1:8af4dc49db9e
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     change in shared clone
  
  changeset:   0:d3873e73d99e
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     init
  
  $ hg update
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat a             # should be two lines of "a"
  a
  a

commit in original

  $ echo b > b
  $ hg commit -A -m'another file'
  adding b

check in shared clone

  $ cd ../repo2
  $ hg log
  changeset:   2:c2e0ac586386
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     another file
  
  changeset:   1:8af4dc49db9e
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     change in shared clone
  
  changeset:   0:d3873e73d99e
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     init
  
  $ hg update
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat b             # should exist with one "b"
  b

hg serve shared clone

  $ hg serve -n test -p $HGPORT -d --pid-file=hg.pid
  $ cat hg.pid >> $DAEMON_PIDS
  $ "$TESTDIR/get-with-headers.py" localhost:$HGPORT '/raw-file/'
  200 Script output follows
  
  
  -rw-r--r-- 4 a
  -rw-r--r-- 2 b