view tests/test-repo-compengines.t @ 32005:2406dbba49bd

serve: add support for Mercurial subrepositories

I've been using `hg serve --web-conf ...` with a simple '/=projects/**' [paths]
configuration for awhile without issue.  Let's ditch the need for the manual
configuration in this case, and limit the repos served to the actual subrepos.

This doesn't attempt to handle the case where a new subrepo appears while the
server is running.  That could probably be handled with a hook if somebody wants
it.  But it's such a rare case, it probably doesn't matter for the temporary
serves.

The main repo is served at '/', just like a repository without subrepos.  I'm
not sure why the duplicate 'adding ...' lines appear on Linux.  They don't
appear on Windows (see 594dd384803c), so they are optional.

Subrepositories that are configured with '../path' or absolute paths are not
cloneable from the server.  (They aren't cloneable locally either, unless they
also exist at their configured source, perhaps via the share extension.)  They
are still served, so that they can be browsed, or cloned individually.  If we
care about that cloning someday, we can probably just add the extra entries to
the webconf dictionary.  Even if the entries use '../' to escape the root, only
the related subrepositories would end up in the dictionary.

A new repository uses zlib storage, which doesn't need a requirement

  $ hg init default
  $ cd default
  $ cat .hg/requires
  dotencode
  fncache
  generaldelta
  revlogv1
  store

  $ touch foo
  $ hg -q commit -A -m 'initial commit with a lot of repeated repeated repeated text to trigger compression'
  $ hg debugrevlog -c | grep 0x78
      0x78 (x)  :   1 (100.00%)
      0x78 (x)  : 110 (100.00%)

  $ cd ..

Unknown compression engine to format.compression aborts

  $ hg --config experimental.format.compression=unknown init unknown
  abort: compression engine unknown defined by experimental.format.compression not available
  (run "hg debuginstall" to list available compression engines)
  [255]

A requirement specifying an unknown compression engine results in bail

  $ hg init unknownrequirement
  $ cd unknownrequirement
  $ echo exp-compression-unknown >> .hg/requires
  $ hg log
  abort: repository requires features unknown to this Mercurial: exp-compression-unknown!
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]

  $ cd ..

#if zstd

  $ hg --config experimental.format.compression=zstd init zstd
  $ cd zstd
  $ cat .hg/requires
  dotencode
  exp-compression-zstd
  fncache
  generaldelta
  revlogv1
  store

  $ touch foo
  $ hg -q commit -A -m 'initial commit with a lot of repeated repeated repeated text'

  $ hg debugrevlog -c | grep 0x28
      0x28      :  1 (100.00%)
      0x28      : 98 (100.00%)

  $ cd ..

Specifying a new format.compression on an existing repo won't introduce data
with that engine or a requirement

  $ cd default
  $ touch bar
  $ hg --config experimental.format.compression=zstd -q commit -A -m 'add bar with a lot of repeated repeated repeated text'

  $ cat .hg/requires
  dotencode
  fncache
  generaldelta
  revlogv1
  store

  $ hg debugrevlog -c | grep 0x78
      0x78 (x)  :   2 (100.00%)
      0x78 (x)  : 199 (100.00%)

#endif