view tests/test-remotefilelog-tags.t @ 41247:a89b20a49c13

rust-cpython: using MissingAncestors from Python code

As precedently done with LazyAncestors on cpython.rs, we test for the
presence of the 'rustext' module.

incrementalmissingrevs() has two callers within the Mercurial core:
`setdiscovery.partialdiscovery` and the `only()` revset.

This move shows a significant discovery performance improvement
in cases where the baseline is slow: using perfdiscovery on the PyPy
repos, prepared with `contrib/discovery-helper <repo> 50 100`, we
get averaged medians of 403ms with the Rust version vs 742ms without
(about 45% better).

But there are still indications that performance can be worse in cases
the baseline is fast, possibly due to the conversion from Python to
Rust and back becoming the bottleneck. We could measure this on
mozilla-central in cases were the delta is just a few changesets.
This requires confirmation, but if that's the reason, then an
upcoming `partialdiscovery` fully in Rust should solve the problem.

Differential Revision: https://phab.mercurial-scm.org/D5551

#require no-windows

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

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > server=True
  > EOF
  $ echo x > foo
  $ echo y > bar
  $ hg commit -qAm one
  $ hg tag tag1
  $ cd ..

# clone with tags

  $ hg clone --shallow ssh://user@dummy/master shallow --noupdate --config remotefilelog.excludepattern=.hgtags
  streaming all changes
  3 files to transfer, 662 bytes of data
  transferred 662 bytes in * seconds (*/sec) (glob)
  searching for changes
  no changes found
  $ cat >> shallow/.hg/hgrc <<EOF
  > [remotefilelog]
  > cachepath=$PWD/hgcache
  > debug=True
  > reponame = master
  > excludepattern=.hgtags
  > [extensions]
  > remotefilelog=
  > EOF

  $ cd shallow
  $ ls .hg/store/data
  ~2ehgtags.i
  $ hg tags
  tip                                1:6ce44dcfda68
  tag1                               0:e0360bc0d9e1
  $ hg update
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)

# pull with tags

  $ cd ../master
  $ hg tag tag2
  $ cd ../shallow
  $ hg pull
  pulling from ssh://user@dummy/master
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files
  new changesets 6a22dfa4fd34
  (run 'hg update' to get a working copy)
  $ hg tags
  tip                                2:6a22dfa4fd34
  tag2                               1:6ce44dcfda68
  tag1                               0:e0360bc0d9e1
  $ hg update
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ ls .hg/store/data
  ~2ehgtags.i

  $ hg log -l 1 --stat
  changeset:   2:6a22dfa4fd34
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag tag2 for changeset 6ce44dcfda68
  
   .hgtags |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)