view tests/test-bundle-type.t @ 33289:abd7dedbaa36

sparse: vendor Facebook-developed extension

Facebook has developed an extension to enable "sparse" checkouts -
a working directory with a subset of files. This feature is a critical
component in enabling repositories to scale to infinite number of
files while retaining reasonable performance. It's worth noting
that sparse checkout is only one possible solution to this problem:
another is virtual filesystems that realize files on first access.
But given that virtual filesystems may not be accessible to all
users, sparse checkout is necessary as a fallback.

Per mailing list discussion at
https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-March/095868.html
we want to add sparse checkout to the Mercurial distribution via
roughly the following mechanism:

1. Vendor extension as-is with minimal modifications (this patch)
2. Refactor extension so it is more clearly experimental and inline
   with Mercurial practices
3. Move code from extension into core where possible
4. Drop experimental labeling and/or move feature into core
   after sign-off from narrow clone feature owners

This commit essentially copies the sparse extension and tests
from revision 71e0a2aeca92a4078fe1b8c76e32c88ff1929737 of the
https://bitbucket.org/facebook/hg-experimental repository.

A list of modifications made as part of vendoring is as follows:

* "EXPERIMENTAL" added to module docstring
* Imports were changed to match Mercurial style conventions
* "testedwith" value was updated to core Mercurial special value and
  comment boilerplate was inserted
* A "clone_sparse" function was renamed to "clonesparse" to appease
  the style checker
* Paths to the sparse extension in tests reflect built-in location
* test-sparse-extensions.t was renamed to test-sparse-fsmonitor.t
  and references to "simplecache" were removed. The test always skips
  because it isn't trivial to run it given the way we currently run
  fsmonitor tests
* A double empty line was removed from test-sparse-profiles.t

There are aspects of the added code that are obviously not ideal.
The goal is to make a minimal number of modifications as part of
the vendoring to make it easier to track changes from the original
implementation. Refactoring will occur in subsequent patches.

  $ cat << EOF >> $HGRCPATH
  > [format]
  > usegeneraldelta=yes
  > EOF

bundle w/o type option

  $ hg init t1
  $ hg init t2
  $ cd t1
  $ echo blablablablabla > file.txt
  $ hg ci -Ama
  adding file.txt
  $ hg log | grep summary
  summary:     a
  $ hg bundle ../b1 ../t2
  searching for changes
  1 changesets found

  $ cd ../t2
  $ hg pull ../b1
  pulling from ../b1
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  (run 'hg update' to get a working copy)
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg log | grep summary
  summary:     a
  $ cd ..

Unknown compression type is rejected

  $ hg init t3
  $ cd t3
  $ hg -q pull ../b1
  $ hg bundle -a -t unknown out.hg
  abort: unknown is not a recognized bundle specification
  (see 'hg help bundlespec' for supported values for --type)
  [255]

  $ hg bundle -a -t unknown-v2 out.hg
  abort: unknown compression is not supported
  (see 'hg help bundlespec' for supported values for --type)
  [255]

  $ cd ..

test bundle types

  $ testbundle() {
  >   echo % test bundle type $1
  >   hg init t$1
  >   cd t1
  >   hg bundle -t $1 ../b$1 ../t$1
  >   f -q -B6 -D ../b$1; echo
  >   cd ../t$1
  >   hg debugbundle ../b$1
  >   hg debugbundle --spec ../b$1
  >   echo
  >   cd ..
  > }

  $ for t in "None" "bzip2" "gzip" "none-v2" "v2" "v1" "gzip-v1"; do
  >   testbundle $t
  > done
  % test bundle type None
  searching for changes
  1 changesets found
  HG20\x00\x00 (esc)
  Stream params: {}
  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  none-v2
  
  % test bundle type bzip2
  searching for changes
  1 changesets found
  HG20\x00\x00 (esc)
  Stream params: sortdict([('Compression', 'BZ')])
  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  bzip2-v2
  
  % test bundle type gzip
  searching for changes
  1 changesets found
  HG20\x00\x00 (esc)
  Stream params: sortdict([('Compression', 'GZ')])
  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  gzip-v2
  
  % test bundle type none-v2
  searching for changes
  1 changesets found
  HG20\x00\x00 (esc)
  Stream params: {}
  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  none-v2
  
  % test bundle type v2
  searching for changes
  1 changesets found
  HG20\x00\x00 (esc)
  Stream params: sortdict([('Compression', 'BZ')])
  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  bzip2-v2
  
  % test bundle type v1
  searching for changes
  1 changesets found
  HG10BZ
  c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  bzip2-v1
  
  % test bundle type gzip-v1
  searching for changes
  1 changesets found
  HG10GZ
  c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  gzip-v1
  

Compression level can be adjusted for bundle2 bundles

  $ hg init test-complevel
  $ cd test-complevel

  $ cat > file0 << EOF
  > this is a file
  > with some text
  > and some more text
  > and other content
  > EOF
  $ cat > file1 << EOF
  > this is another file
  > with some other content
  > and repeated, repeated, repeated, repeated content
  > EOF
  $ hg -q commit -A -m initial

  $ hg bundle -a -t gzip-v2 gzip-v2.hg
  1 changesets found
  $ f --size gzip-v2.hg
  gzip-v2.hg: size=427

  $ hg --config experimental.bundlecomplevel=1 bundle -a -t gzip-v2 gzip-v2-level1.hg
  1 changesets found
  $ f --size gzip-v2-level1.hg
  gzip-v2-level1.hg: size=435

  $ cd ..

#if zstd

  $ for t in "zstd" "zstd-v2"; do
  >   testbundle $t
  > done
  % test bundle type zstd
  searching for changes
  1 changesets found
  HG20\x00\x00 (esc)
  Stream params: sortdict([('Compression', 'ZS')])
  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  zstd-v2
  
  % test bundle type zstd-v2
  searching for changes
  1 changesets found
  HG20\x00\x00 (esc)
  Stream params: sortdict([('Compression', 'ZS')])
  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
  zstd-v2
  

Explicit request for zstd on non-generaldelta repos

  $ hg --config format.usegeneraldelta=false init nogd
  $ hg -q -R nogd pull t1
  $ hg -R nogd bundle -a -t zstd nogd-zstd
  1 changesets found

zstd-v1 always fails

  $ hg -R tzstd bundle -a -t zstd-v1 zstd-v1
  abort: compression engine zstd is not supported on v1 bundles
  (see 'hg help bundlespec' for supported values for --type)
  [255]

#else

zstd is a valid engine but isn't available

  $ hg -R t1 bundle -a -t zstd irrelevant.hg
  abort: compression engine zstd could not be loaded
  [255]

#endif

test garbage file

  $ echo garbage > bgarbage
  $ hg init tgarbage
  $ cd tgarbage
  $ hg pull ../bgarbage
  pulling from ../bgarbage
  abort: ../bgarbage: not a Mercurial bundle
  [255]
  $ cd ..

test invalid bundle type

  $ cd t1
  $ hg bundle -a -t garbage ../bgarbage
  abort: garbage is not a recognized bundle specification
  (see 'hg help bundlespec' for supported values for --type)
  [255]
  $ cd ..