tests/test-remotefilelog-pull-noshallow.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.

#require no-windows

  $ . "$TESTDIR/remotefilelog-library.sh"

Set up an extension to make sure remotefilelog clientsetup() runs
unconditionally even if we have never used a local shallow repo.
This mimics behavior when using remotefilelog with chg.  clientsetup() can be
triggered due to a shallow repo, and then the code can later interact with
non-shallow repositories.

  $ cat > setupremotefilelog.py << EOF
  > from mercurial import extensions
  > def extsetup(ui):
  >     remotefilelog = extensions.find(b'remotefilelog')
  >     remotefilelog.onetimeclientsetup(ui)
  > EOF

Set up the master repository to pull from.

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > server=True
  > EOF
  $ echo x > x
  $ hg commit -qAm x

  $ cd ..

  $ hg clone ssh://user@dummy/master child -q

We should see the remotefilelog capability here, which advertises that
the server supports our custom getfiles method.

  $ cd master
  $ echo 'hello' | hg -R . serve --stdio | grep capa | identifyrflcaps
  exp-remotefilelog-ssh-getfiles-1
  x_rfl_getfile
  x_rfl_getflogheads
  $ echo 'capabilities' | hg -R . serve --stdio | identifyrflcaps ; echo
  exp-remotefilelog-ssh-getfiles-1
  x_rfl_getfile
  x_rfl_getflogheads
  

Pull to the child repository.  Use our custom setupremotefilelog extension
to ensure that remotefilelog.onetimeclientsetup() gets triggered.  (Without
using chg it normally would not be run in this case since the local repository
is not shallow.)

  $ echo y > y
  $ hg commit -qAm y

  $ cd ../child
  $ hg pull --config extensions.setuprfl=$TESTTMP/setupremotefilelog.py
  pulling from ssh://user@dummy/master
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets d34c38483be9
  (run 'hg update' to get a working copy)

  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cat y
  y

Test that bundle works in a non-remotefilelog repo w/ remotefilelog loaded

  $ echo y >> y
  $ hg commit -qAm "modify y"
  $ hg bundle --base ".^" --rev . mybundle.hg --config extensions.setuprfl=$TESTTMP/setupremotefilelog.py
  1 changesets found

  $ cd ..