tests/test-rebase-backup.t

rust-matchers: fix quadratic complexity in `FileMatcher`

Concretely, this command:

```
$ echo hg up -r <nodeid>; time hg revert dir1 dir2 -r <othernode> --debug
hg up -r <nodeid>

real	0m14.690s
user	0m14.766s
sys	0m5.430s
```

was much slower despite using 16 cores before this change.
The approach taken here is the same one used in match.py, in exactmatcher.

This changeset was originally written by Valentin Gatien-Baron in a private
repository.
I have redacted the commit message and did a minor clean up of the code.

  $ cat << EOF >> $HGRCPATH
  > [extensions]
  > rebase=
  > EOF

==================================
Test backup-bundle config option |
==================================
Test with Pre-obsmarker rebase:
1) When config option is not set:
  $ hg init repo1
  $ cd repo1
  $ echo a>a
  $ hg ci -qAma
  $ echo b>b
  $ hg ci -qAmb
  $ echo c>c
  $ hg ci -qAmc
  $ hg up 0 -q
  $ echo d>d
  $ hg ci -qAmd
  $ echo e>e
  $ hg ci -qAme
  $ hg log -GT "{rev}: {firstline(desc)}\n"
  @  4: e
  |
  o  3: d
  |
  | o  2: c
  | |
  | o  1: b
  |/
  o  0: a
  
  $ hg rebase -s 1 -d .
  rebasing 1:d2ae7f538514 "b"
  rebasing 2:177f92b77385 "c"
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/d2ae7f538514-c7ed7a78-rebase.hg
  $ hg log -GT "{rev}: {firstline(desc)}\n"
  o  4: c
  |
  o  3: b
  |
  @  2: e
  |
  o  1: d
  |
  o  0: a
  

2) When config option is set:
  $ cat << EOF >> $HGRCPATH
  > [rewrite]
  > backup-bundle = False
  > EOF

  $ echo f>f
  $ hg ci -Aqmf
  $ echo g>g
  $ hg ci -Aqmg
  $ hg log -GT "{rev}: {firstline(desc)}\n"
  @  6: g
  |
  o  5: f
  |
  | o  4: c
  | |
  | o  3: b
  |/
  o  2: e
  |
  o  1: d
  |
  o  0: a
  
  $ hg rebase -s 3 -d .
  rebasing 3:05bff2a95b12 "b"
  rebasing 4:1762bde4404d "c"

  $ hg log -GT "{rev}: {firstline(desc)}\n"
  o  6: c
  |
  o  5: b
  |
  @  4: g
  |
  o  3: f
  |
  o  2: e
  |
  o  1: d
  |
  o  0: a
  
Test when rebased revisions are stripped during abort:
======================================================

  $ echo conflict > c
  $ hg ci -Am "conflict with c"
  adding c
  created new head
  $ hg log -GT "{rev}: {firstline(desc)}\n"
  @  7: conflict with c
  |
  | o  6: c
  | |
  | o  5: b
  |/
  o  4: g
  |
  o  3: f
  |
  o  2: e
  |
  o  1: d
  |
  o  0: a
  
When backup-bundle = True:
  $ cat << EOF >> $HGRCPATH
  > [rewrite]
  > backup-bundle = True
  > EOF
  $ hg rebase -s 5 -d .
  rebasing 5:1f8148a544ee "b"
  rebasing 6:f8bc7d28e573 "c"
  merging c
  warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]
  $ hg rebase --abort
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/818c1a43c916-2b644d96-backup.hg
  rebase aborted

When backup-bundle = False:
  $ cat << EOF >> $HGRCPATH
  > [rewrite]
  > backup-bundle = False
  > EOF
  $ hg rebase -s 5 -d .
  rebasing 5:1f8148a544ee "b"
  rebasing 6:f8bc7d28e573 "c"
  merging c
  warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]
  $ hg rebase --abort
  rebase aborted
  $ cd ..