view tests/test-mq-symlinks.t @ 26755:bb0b955d050d

streamclone: support for producing and consuming stream clone bundles

Up to this point, stream clones only existed as a dynamically generated
data format produced and consumed during streaming clones. In order to
support this efficient cloning format with the clone bundles feature, we
need a more formal, on disk representation of the streaming clone data.

This patch introduces a new "bundle" type for streaming clones. Unlike
existing bundles, it does not contain changegroup data. It does,
however, share the same concepts like the 4 byte header which identifies
the type of data that follows and the 2 byte abbreviation for
compression types (of which only "UN" is currently supported).

The new bundle format is essentially the existing stream clone version 1
data format with some headers at the beginning.

Content negotiation at stream clone request time checked for repository
format/requirements compatibility before initiating a stream clone. We
can't do active content negotiation when using clone bundles. So, we put
this set of requirements inside the payload so consumers have a built-in
mechanism for checking compatibility before reading and applying lots of
data. Of course, we will also advertise this requirements set in clone
bundles. But that's for another patch.

We currently don't have a mechanism to produce and consume this new
bundle format. This will be implemented in upcoming patches.

It's worth noting that if a legacy client attempts to `hg unbundle` a
stream clone bundle (with the "HGS1" header), it will abort with:
"unknown bundle version S1," which seems appropriate.

#require symlink

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

  $ hg init
  $ hg qinit
  $ hg qnew base.patch
  $ echo aaa > a
  $ echo bbb > b
  $ echo ccc > c
  $ hg add a b c
  $ hg qrefresh
  $ readlink.py a
  a -> a not a symlink


test replacing a file with a symlink

  $ hg qnew symlink.patch
  $ rm a
  $ ln -s b a
  $ hg qrefresh --git
  $ readlink.py a
  a -> b

  $ hg qpop
  popping symlink.patch
  now at: base.patch
  $ hg qpush
  applying symlink.patch
  now at: symlink.patch
  $ readlink.py a
  a -> b


test updating a symlink

  $ rm a
  $ ln -s c a
  $ hg qnew --git -f updatelink
  $ readlink.py a
  a -> c
  $ hg qpop
  popping updatelink
  now at: symlink.patch
  $ hg qpush --debug
  applying updatelink
  patching file a
  committing files:
  a
  committing manifest
  committing changelog
  now at: updatelink
  $ readlink.py a
  a -> c
  $ hg st


test replacing a symlink with a file

  $ ln -s c s
  $ hg add s
  $ hg qnew --git -f addlink
  $ rm s
  $ echo sss > s
  $ hg qnew --git -f replacelinkwithfile
  $ hg qpop
  popping replacelinkwithfile
  now at: addlink
  $ hg qpush
  applying replacelinkwithfile
  now at: replacelinkwithfile
  $ cat s
  sss
  $ hg st


test symlink removal

  $ hg qnew removesl.patch
  $ hg rm a
  $ hg qrefresh --git
  $ hg qpop
  popping removesl.patch
  now at: replacelinkwithfile
  $ hg qpush
  applying removesl.patch
  now at: removesl.patch
  $ hg st -c
  C b
  C c
  C s

replace broken symlink with another broken symlink

  $ ln -s linka linka
  $ hg add linka
  $ hg qnew link
  $ hg mv linka linkb
  $ rm linkb
  $ ln -s linkb linkb
  $ hg qnew movelink
  $ hg qpop
  popping movelink
  now at: link
  $ hg qpush
  applying movelink
  now at: movelink
  $ readlink.py linkb
  linkb -> linkb