view tests/test-repo-compengines.t @ 35280:8e72f9152c4d

lfs: introduce a user level cache for lfs files

This is the same mechanism in place for largefiles, and solves several problems
working with multiple local repositories.  The existing largefiles method is
reused in place, because I suspect that there are other functions that can be
shared.  If we wait a bit to identify more before `hg cp lfutil.py ...`, the
history will be easier to trace.

The push between repo14 and repo15 in test-lfs.t arguably shouldn't be uploading
any files with a local push.  Maybe we can revisit that when `hg push` without
'lfs.url' can upload files to the push destination.  Then it would be consistent
for blobs in a local push to be linked to the local destination's cache.

The cache property is added to run-tests.py, the same as the largefiles
property, so that test generated files don't pollute the real location.  Having
files available locally broke a couple existing lfs-test-server tests, so the
cache is cleared in a few places to force file download.

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