tests/test-histedit-bookmark-motion.t

test: simplify test-amend.t to avoid race condition

Insted on relying on sleep, we could simply have the editor do the file change.
This remove the reliance on "sleep" and avoid test failing on heavy load
machine.

To test this, I reverted the code change in 5558e3437872 and the test started
failing again.

This is a graft on stable of 141ceec06b55 which should have targeted for stable.

Differential Revision: https://phab.mercurial-scm.org/D8103

  $ . "$TESTDIR/histedit-helpers.sh"

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

  $ hg init r
  $ cd r

  $ for x in a b c d e f ; do
  >     echo $x > $x
  >     hg add $x
  >     hg ci -m $x
  > done

  $ hg book -r 1 will-move-backwards
  $ hg book -r 2 two
  $ hg book -r 2 also-two
  $ hg book -r 3 three
  $ hg book -r 4 four
  $ hg book -r tip five
  $ hg log --graph
  @  changeset:   5:652413bf663e
  |  bookmark:    five
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     f
  |
  o  changeset:   4:e860deea161a
  |  bookmark:    four
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     e
  |
  o  changeset:   3:055a42cdd887
  |  bookmark:    three
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     d
  |
  o  changeset:   2:177f92b77385
  |  bookmark:    also-two
  |  bookmark:    two
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c
  |
  o  changeset:   1:d2ae7f538514
  |  bookmark:    will-move-backwards
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     b
  |
  o  changeset:   0:cb9a9f314b8b
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     a
  
  $ HGEDITOR=cat hg histedit 1
  pick d2ae7f538514 1 b
  pick 177f92b77385 2 c
  pick 055a42cdd887 3 d
  pick e860deea161a 4 e
  pick 652413bf663e 5 f
  
  # Edit history between d2ae7f538514 and 652413bf663e
  #
  # Commits are listed from least to most recent
  #
  # You can reorder changesets by reordering the lines
  #
  # Commands:
  #
  #  e, edit = use commit, but stop for amending
  #  m, mess = edit commit message without changing commit content
  #  p, pick = use commit
  #  b, base = checkout changeset and apply further changesets from there
  #  d, drop = remove commit from history
  #  f, fold = use commit, but combine it with the one above
  #  r, roll = like fold, but discard this commit's description and date
  #
  $ hg histedit 1 --commands - --verbose << EOF | grep histedit
  > pick 177f92b77385 2 c
  > drop d2ae7f538514 1 b
  > pick 055a42cdd887 3 d
  > fold e860deea161a 4 e
  > pick 652413bf663e 5 f
  > EOF
  saved backup bundle to $TESTTMP/r/.hg/strip-backup/96e494a2d553-45c027ab-histedit.hg
  $ hg log --graph
  @  changeset:   3:cacdfd884a93
  |  bookmark:    five
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     f
  |
  o  changeset:   2:59d9f330561f
  |  bookmark:    four
  |  bookmark:    three
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     d
  |
  o  changeset:   1:b346ab9a313d
  |  bookmark:    also-two
  |  bookmark:    two
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c
  |
  o  changeset:   0:cb9a9f314b8b
     bookmark:    will-move-backwards
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     a
  
  $ HGEDITOR=cat hg histedit 1
  pick b346ab9a313d 1 c
  pick 59d9f330561f 2 d
  pick cacdfd884a93 3 f
  
  # Edit history between b346ab9a313d and cacdfd884a93
  #
  # Commits are listed from least to most recent
  #
  # You can reorder changesets by reordering the lines
  #
  # Commands:
  #
  #  e, edit = use commit, but stop for amending
  #  m, mess = edit commit message without changing commit content
  #  p, pick = use commit
  #  b, base = checkout changeset and apply further changesets from there
  #  d, drop = remove commit from history
  #  f, fold = use commit, but combine it with the one above
  #  r, roll = like fold, but discard this commit's description and date
  #
  $ hg histedit 1 --commands - --verbose << EOF | grep histedit
  > pick b346ab9a313d 1 c
  > pick cacdfd884a93 3 f
  > pick 59d9f330561f 2 d
  > EOF
  saved backup bundle to $TESTTMP/r/.hg/strip-backup/59d9f330561f-073008af-histedit.hg

We expect 'five' to stay at tip, since the tipmost bookmark is most
likely the useful signal.

  $ hg log --graph
  @  changeset:   3:c04e50810e4b
  |  bookmark:    five
  |  bookmark:    four
  |  bookmark:    three
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     d
  |
  o  changeset:   2:c13eb81022ca
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     f
  |
  o  changeset:   1:b346ab9a313d
  |  bookmark:    also-two
  |  bookmark:    two
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c
  |
  o  changeset:   0:cb9a9f314b8b
     bookmark:    will-move-backwards
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     a