view tests/test-histedit-bookmark-motion.t @ 20182:04036798ebed

branches: avoid unnecessary changectx.branch() calls

This requires reading from the changelog, which can be costly over NFS.

Note that this does not totally remove reading from the changelog; we
still do that when calling changectx.closesbranch(). That call will be
removed in a later patch.

Running hg branches on the PyPy repo (with 996) over a busy NFS server,
before this change:

$ time hg --profile branches > /dev/null
   CallCount    Recursive     Total(s)    Inline(s) module:lineno(function)
        2042            0      2.2827      2.2827   <open>
        2036            0      0.9840      0.9840   <method 'close' of 'file' objects>
        2036            0      0.0464      0.0464   <method 'read' of 'file' objects>
        5233            0      0.1985      0.0453   mercurial.repoview:161(changelog)
       10462            0      0.0791      0.0314       mercurial.changelog:133(tip)
        5233            0      0.0388      0.0176       mercurial.localrepo:26(__get__)
       10462            0      0.0250      0.0126       <len>
        5233            0      0.0059      0.0039       mercurial.repoview:112(filterrevs)
       10462            0      0.0029      0.0029       <hash>
        2034            0      0.0444      0.0444   <method 'seek' of 'file' objects>
        5340            0      0.0390      0.0390   mercurial.revlog:296(rev)
        2582            0      0.0371      0.0371   <zlib.decompress>
        3155            0      0.1963      0.0366   mercurial.context:202(__init__)
        3155            0      0.1238      0.0306       mercurial.repoview:161(changelog)
        3155            0      0.0261      0.0080       mercurial.changelog:183(rev)
        9465            0      0.0061      0.0061       <isinstance>
        1096            0      0.0023      0.0023       <binascii.unhexlify>
        4251            0      0.0014      0.0014       <len>
        2059            0      3.7341      0.0332   mercurial.changelog:270(read)
        2059            0      3.6304      0.0307       mercurial.revlog:907(revision)
        2057            0      0.0262      0.0137       mercurial.changelog:28(decodeextra)
        4118            0      0.0094      0.0094       <method 'split' of 'str' objects>
        4118            0      0.0270      0.0048       mercurial.encoding:61(tolocal)
        2059            0      0.0040      0.0040       <method 'index' of 'str' objects>
       10462            0      0.0791      0.0314   mercurial.changelog:133(tip)
       10462            0      0.0289      0.0207       mercurial.changelog:190(node)
       10462            0      0.0188      0.0091       <len>
       52433        20932      0.0478      0.0310   <len>
       20932            0      0.0221      0.0168       mercurial.revlog:262(__len__)
        2059            0      3.6304      0.0307   mercurial.revlog:907(revision)

real    0m4.361s
user    0m0.986s
sys     0m0.237s

After this change:

$ time hg --profile branches > /dev/null
   CallCount    Recursive     Total(s)    Inline(s) module:lineno(function)
        1069            0      1.1098      1.1098   <open>
        1063            0      0.4865      0.4865   <method 'close' of 'file' objects>
        4122            0      0.1811      0.0404   mercurial.repoview:161(changelog)
        8240            0      0.0712      0.0272       mercurial.changelog:133(tip)
        4122            0      0.0378      0.0177       mercurial.localrepo:26(__get__)
        8240            0      0.0221      0.0115       <len>
        4122            0      0.0057      0.0033       mercurial.repoview:112(filterrevs)
        8240            0      0.0025      0.0025       <hash>
        3029            0      0.1979      0.0371   mercurial.context:202(__init__)
        3029            0      0.1278      0.0310       mercurial.repoview:161(changelog)
        3029            0      0.0230      0.0081       mercurial.changelog:183(rev)
        9087            0      0.0061      0.0061       <isinstance>
        1096            0      0.0026      0.0026       <binascii.unhexlify>
        4125            0      0.0014      0.0014       <len>
        4229            0      0.0337      0.0337   mercurial.revlog:296(rev)
        1061            0      0.0296      0.0296   <method 'seek' of 'file' objects>
        1063            0      0.0292      0.0292   <method 'read' of 'file' objects>
        8240            0      0.0712      0.0272   mercurial.changelog:133(tip)
        8240            0      0.0271      0.0196       mercurial.changelog:190(node)
        8240            0      0.0169      0.0083       <len>
       40476        16488      0.0422      0.0271   <len>
       16488            0      0.0193      0.0152       mercurial.revlog:262(__len__)
        1342            0      0.0241      0.0241   <zlib.decompress>
        9445            0      0.0336      0.0224   mercurial.changelog:190(node)
        9445            0      0.0112      0.0112       mercurial.revlog:317(node)
        1074            0      1.9102      0.0224   mercurial.changelog:270(read)
        1074            0      1.8397      0.0202       mercurial.revlog:907(revision)
        1073            0      0.0187      0.0099       mercurial.changelog:28(decodeextra)
        2148            0      0.0061      0.0061       <method 'split' of 'str' objects>
        2148            0      0.0184      0.0034       mercurial.encoding:61(tolocal)

real    0m2.402s
user    0m0.735s
sys     0m0.177s

  $ . "$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
  #
  # Commands:
  #  p, pick = use commit
  #  e, edit = use commit, but stop for amending
  #  f, fold = use commit, but fold into previous commit (combines N and N-1)
  #  d, drop = remove commit from history
  #  m, mess = edit message without changing commit content
  #
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ 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
  histedit: moving bookmarks also-two from 177f92b77385 to b346ab9a313d
  histedit: moving bookmarks five from 652413bf663e to cacdfd884a93
  histedit: moving bookmarks four from e860deea161a to 59d9f330561f
  histedit: moving bookmarks three from 055a42cdd887 to 59d9f330561f
  histedit: moving bookmarks two from 177f92b77385 to b346ab9a313d
  histedit: moving bookmarks will-move-backwards from d2ae7f538514 to cb9a9f314b8b
  saved backup bundle to $TESTTMP/r/.hg/strip-backup/d2ae7f538514-backup.hg (glob)
  saved backup bundle to $TESTTMP/r/.hg/strip-backup/96e494a2d553-backup.hg (glob)
  $ 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
  #
  # Commands:
  #  p, pick = use commit
  #  e, edit = use commit, but stop for amending
  #  f, fold = use commit, but fold into previous commit (combines N and N-1)
  #  d, drop = remove commit from history
  #  m, mess = edit message without changing commit content
  #
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg histedit 1 --commands - --verbose << EOF | grep histedit
  > pick b346ab9a313d 1 c
  > pick cacdfd884a93 3 f
  > pick 59d9f330561f 2 d
  > EOF
  histedit: moving bookmarks five from cacdfd884a93 to c04e50810e4b
  histedit: moving bookmarks four from 59d9f330561f to c04e50810e4b
  histedit: moving bookmarks three from 59d9f330561f to c04e50810e4b
  saved backup bundle to $TESTTMP/r/.hg/strip-backup/59d9f330561f-backup.hg (glob)

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