view tests/test-histedit-outgoing.t @ 22778:80f2b63dd83a

parsers: add a function to efficiently lowercase ASCII strings

We need a way to efficiently lowercase ASCII strings. For example, 'hg status'
needs to build up the fold map -- a map from a canonical case (for OS X,
lowercase) to the actual case of each file and directory in the dirstate.

The current way we do that is to try decoding to ASCII and then calling
lower() on the string, labeled 'orig' below:

    str.decode('ascii')
    return str.lower()

This is pretty inefficient, and it turns out we can do much better.

I also tested out a condition-based approach, labeled 'cond' below:

    (c >= 'A' && c <= 'Z') ? (c + ('a' - 'A')) : c

'cond' turned out to be slower in all cases. A 256-byte lookup table with
invalid values for everything past 127 performed similarly, but this was less
verbose.

On OS X 10.9 with LLVM version 6.0 (clang-600.0.51), the asciilower function
was run against two corpuses.

Corpus 1 (list of files from real-world repo, > 100k files):
orig:   wall 0.428567 comb 0.430000 user 0.430000 sys 0.000000 (best of 24)
cond:   wall 0.077204 comb 0.070000 user 0.070000 sys 0.000000 (best of 100)
lookup: wall 0.060714 comb 0.060000 user 0.060000 sys 0.000000 (best of 100)

Corpus 2 (mozilla-central, 113k files):
orig:   wall 0.238406 comb 0.240000 user 0.240000 sys 0.000000 (best of 42)
cond:   wall 0.040779 comb 0.040000 user 0.040000 sys 0.000000 (best of 100)
lookup: wall 0.037623 comb 0.040000 user 0.040000 sys 0.000000 (best of 100)

On a Linux server-class machine with GCC 4.4.6 20120305 (Red Hat 4.4.6-4):

Corpus 1 (real-world repo, > 100k files):
orig:   wall 0.260899 comb 0.260000 user 0.260000 sys 0.000000 (best of 38)
cond:   wall 0.054818 comb 0.060000 user 0.060000 sys 0.000000 (best of 100)
lookup: wall 0.048489 comb 0.050000 user 0.050000 sys 0.000000 (best of 100)

Corpus 2 (mozilla-central, 113k files):
orig:   wall 0.153082 comb 0.150000 user 0.150000 sys 0.000000 (best of 65)
cond:   wall 0.031007 comb 0.040000 user 0.040000 sys 0.000000 (best of 100)
lookup: wall 0.028793 comb 0.030000 user 0.030000 sys 0.000000 (best of 100)

SSE instructions might help even more, but I didn't experiment with those.

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

  $ initrepos ()
  > {
  >     hg init r
  >     cd r
  >     for x in a b c ; do
  >         echo $x > $x
  >         hg add $x
  >         hg ci -m $x
  >     done
  >     cd ..
  >     hg clone r r2 | grep -v updating
  >     cd r2
  >     for x in d e f ; do
  >         echo $x > $x
  >         hg add $x
  >         hg ci -m $x
  >     done
  >     cd ..
  >     hg init r3
  >     cd r3
  >     for x in g h i ; do
  >         echo $x > $x
  >         hg add $x
  >         hg ci -m $x
  >     done
  >     cd ..
  > }

  $ initrepos
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

show the edit commands offered by outgoing
  $ cd r2
  $ HGEDITOR=cat hg histedit --outgoing ../r | grep -v comparing | grep -v searching
  pick 055a42cdd887 3 d
  pick e860deea161a 4 e
  pick 652413bf663e 5 f
  
  # Edit history between 055a42cdd887 and 652413bf663e
  #
  # Commits are listed from least to most recent
  #
  # Commands:
  #  p, pick = use commit
  #  e, edit = use commit, but stop for amending
  #  f, fold = use commit, but combine it with the one above
  #  r, roll = like fold, but discard this commit's description
  #  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
  $ cd ..

show the error from unrelated repos
  $ cd r3
  $ HGEDITOR=cat hg histedit --outgoing ../r | grep -v comparing | grep -v searching
  abort: repository is unrelated
  [1]
  $ cd ..

show the error from unrelated repos
  $ cd r3
  $ HGEDITOR=cat hg histedit --force --outgoing ../r
  comparing with ../r
  searching for changes
  warning: repository is unrelated
  pick 2a4042b45417 0 g
  pick 68c46b4927ce 1 h
  pick 51281e65ba79 2 i
  
  # Edit history between 2a4042b45417 and 51281e65ba79
  #
  # Commits are listed from least to most recent
  #
  # Commands:
  #  p, pick = use commit
  #  e, edit = use commit, but stop for amending
  #  f, fold = use commit, but combine it with the one above
  #  r, roll = like fold, but discard this commit's description
  #  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
  $ cd ..

test sensitivity to branch in URL:

  $ cd r2
  $ hg -q update 2
  $ hg -q branch foo
  $ hg commit -m 'create foo branch'
  $ HGEDITOR=cat hg histedit --outgoing '../r#foo' | grep -v comparing | grep -v searching
  pick f26599ee3441 6 create foo branch
  
  # Edit history between f26599ee3441 and f26599ee3441
  #
  # Commits are listed from least to most recent
  #
  # Commands:
  #  p, pick = use commit
  #  e, edit = use commit, but stop for amending
  #  f, fold = use commit, but combine it with the one above
  #  r, roll = like fold, but discard this commit's description
  #  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

test to check number of roots in outgoing revisions

  $ hg -q outgoing -G --template '{node|short}({branch})' '../r'
  @  f26599ee3441(foo)
  
  o  652413bf663e(default)
  |
  o  e860deea161a(default)
  |
  o  055a42cdd887(default)
  
  $ HGEDITOR=cat hg -q histedit --outgoing '../r'
  abort: there are ambiguous outgoing revisions
  (see "hg help histedit" for more detail)
  [255]

  $ hg -q update -C 2
  $ echo aa >> a
  $ hg -q commit -m 'another head on default'
  $ hg -q outgoing -G --template '{node|short}({branch})' '../r#default'
  @  3879dc049647(default)
  
  o  652413bf663e(default)
  |
  o  e860deea161a(default)
  |
  o  055a42cdd887(default)
  
  $ HGEDITOR=cat hg -q histedit --outgoing '../r#default'
  abort: there are ambiguous outgoing revisions
  (see "hg help histedit" for more detail)
  [255]

  $ cd ..