view tests/test-rebase-issue-noparam-single-rev.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

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > rebase=
  > 
  > [phases]
  > publish=False
  > 
  > [alias]
  > tglog = log -G --template "{rev}: {node|short} '{desc}' {branches}\n"
  > EOF


  $ hg init a
  $ cd a

  $ echo c1 > c1
  $ hg ci -Am c1
  adding c1

  $ echo c2 > c2
  $ hg ci -Am c2
  adding c2

  $ echo l1 > l1
  $ hg ci -Am l1
  adding l1

  $ hg up -q -C 1

  $ echo r1 > r1
  $ hg ci -Am r1
  adding r1
  created new head

  $ echo r2 > r2
  $ hg ci -Am r2
  adding r2

  $ hg tglog
  @  4: 225af64d03e6 'r2'
  |
  o  3: 8d0a8c99b309 'r1'
  |
  | o  2: 87c180a611f2 'l1'
  |/
  o  1: 56daeba07f4b 'c2'
  |
  o  0: e8faad3d03ff 'c1'
  
Rebase with no arguments - single revision in source branch:

  $ hg up -q -C 2

  $ hg rebase
  rebasing 2:87c180a611f2 "l1"
  saved backup bundle to $TESTTMP/a/.hg/strip-backup/87c180a611f2-a5be192d-rebase.hg

  $ hg tglog
  @  4: b1152cc99655 'l1'
  |
  o  3: 225af64d03e6 'r2'
  |
  o  2: 8d0a8c99b309 'r1'
  |
  o  1: 56daeba07f4b 'c2'
  |
  o  0: e8faad3d03ff 'c1'
  
  $ cd ..


  $ hg init b
  $ cd b

  $ echo c1 > c1
  $ hg ci -Am c1
  adding c1

  $ echo c2 > c2
  $ hg ci -Am c2
  adding c2

  $ echo l1 > l1
  $ hg ci -Am l1
  adding l1

  $ echo l2 > l2
  $ hg ci -Am l2
  adding l2

  $ hg up -q -C 1

  $ echo r1 > r1
  $ hg ci -Am r1
  adding r1
  created new head

  $ hg tglog
  @  4: 8d0a8c99b309 'r1'
  |
  | o  3: 1ac923b736ef 'l2'
  | |
  | o  2: 87c180a611f2 'l1'
  |/
  o  1: 56daeba07f4b 'c2'
  |
  o  0: e8faad3d03ff 'c1'
  
Rebase with no arguments - single revision in target branch:

  $ hg up -q -C 3

  $ hg rebase
  rebasing 2:87c180a611f2 "l1"
  rebasing 3:1ac923b736ef "l2"
  saved backup bundle to $TESTTMP/b/.hg/strip-backup/87c180a611f2-b980535c-rebase.hg

  $ hg tglog
  @  4: 023181307ed0 'l2'
  |
  o  3: 913ab52b43b4 'l1'
  |
  o  2: 8d0a8c99b309 'r1'
  |
  o  1: 56daeba07f4b 'c2'
  |
  o  0: e8faad3d03ff 'c1'
  

  $ cd ..