view tests/test-up-local-change.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.

  $ HGMERGE=true; export HGMERGE

  $ hg init r1
  $ cd r1
  $ echo a > a
  $ hg addremove
  adding a
  $ hg commit -m "1"

  $ hg clone . ../r2
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd ../r2
  $ hg up
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo abc > a
  $ hg diff --nodates
  diff -r c19d34741b0a a
  --- a/a
  +++ b/a
  @@ -1,1 +1,1 @@
  -a
  +abc

  $ cd ../r1
  $ echo b > b
  $ echo a2 > a
  $ hg addremove
  adding b
  $ hg commit -m "2"

  $ cd ../r2
  $ hg -q pull ../r1
  $ hg status
  M a
  $ hg parents
  changeset:   0:c19d34741b0a
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     1
  
  $ hg --debug up
    searching for copies back to rev 1
    unmatched files in other:
     b
  resolving manifests
   branchmerge: False, force: False, partial: False
   ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb
   preserving a for resolve of a
   b: remote created -> g
  getting b
  updating: b 1/2 files (50.00%)
   a: versions differ -> m
  updating: a 2/2 files (100.00%)
  picked tool 'true' for a (binary False symlink False)
  merging a
  my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
  1 files updated, 1 files merged, 0 files removed, 0 files unresolved
  $ hg parents
  changeset:   1:1e71731e6fbb
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     2
  
  $ hg --debug up 0
  resolving manifests
   branchmerge: False, force: False, partial: False
   ancestor: 1e71731e6fbb, local: 1e71731e6fbb+, remote: c19d34741b0a
   preserving a for resolve of a
   b: other deleted -> r
  removing b
  updating: b 1/2 files (50.00%)
   a: versions differ -> m
  updating: a 2/2 files (100.00%)
  picked tool 'true' for a (binary False symlink False)
  merging a
  my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb
  0 files updated, 1 files merged, 1 files removed, 0 files unresolved
  $ hg parents
  changeset:   0:c19d34741b0a
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     1
  
  $ hg --debug merge
  abort: nothing to merge
  (use 'hg update' instead)
  [255]
  $ hg parents
  changeset:   0:c19d34741b0a
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     1
  
  $ hg --debug up
    searching for copies back to rev 1
    unmatched files in other:
     b
  resolving manifests
   branchmerge: False, force: False, partial: False
   ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb
   preserving a for resolve of a
   b: remote created -> g
  getting b
  updating: b 1/2 files (50.00%)
   a: versions differ -> m
  updating: a 2/2 files (100.00%)
  picked tool 'true' for a (binary False symlink False)
  merging a
  my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
  1 files updated, 1 files merged, 0 files removed, 0 files unresolved
  $ hg parents
  changeset:   1:1e71731e6fbb
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     2
  
  $ hg -v history
  changeset:   1:1e71731e6fbb
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  files:       a b
  description:
  2
  
  
  changeset:   0:c19d34741b0a
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  files:       a
  description:
  1
  
  
  $ hg diff --nodates
  diff -r 1e71731e6fbb a
  --- a/a
  +++ b/a
  @@ -1,1 +1,1 @@
  -a2
  +abc


create a second head

  $ cd ../r1
  $ hg up 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo b2 > b
  $ echo a3 > a
  $ hg addremove
  adding b
  $ hg commit -m "3"
  created new head

  $ cd ../r2
  $ hg -q pull ../r1
  $ hg status
  M a
  $ hg parents
  changeset:   1:1e71731e6fbb
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     2
  
  $ hg --debug up
  abort: uncommitted changes
  (commit and merge, or update --clean to discard changes)
  [255]
  $ hg --debug merge
  abort: uncommitted changes
  (use 'hg status' to list changes)
  [255]
  $ hg --debug merge -f
    searching for copies back to rev 1
    unmatched files new in both:
     b
  resolving manifests
   branchmerge: True, force: True, partial: False
   ancestor: c19d34741b0a, local: 1e71731e6fbb+, remote: 83c51d0caff4
   preserving a for resolve of a
   preserving b for resolve of b
   a: versions differ -> m
  updating: a 1/2 files (50.00%)
  picked tool 'true' for a (binary False symlink False)
  merging a
  my a@1e71731e6fbb+ other a@83c51d0caff4 ancestor a@c19d34741b0a
   b: versions differ -> m
  updating: b 2/2 files (100.00%)
  picked tool 'true' for b (binary False symlink False)
  merging b
  my b@1e71731e6fbb+ other b@83c51d0caff4 ancestor b@000000000000
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg parents
  changeset:   1:1e71731e6fbb
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     2
  
  changeset:   2:83c51d0caff4
  tag:         tip
  parent:      0:c19d34741b0a
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     3
  
  $ hg diff --nodates
  diff -r 1e71731e6fbb a
  --- a/a
  +++ b/a
  @@ -1,1 +1,1 @@
  -a2
  +abc


test a local add

  $ cd ..
  $ hg init a
  $ hg init b
  $ echo a > a/a
  $ echo a > b/a
  $ hg --cwd a commit -A -m a
  adding a
  $ cd b
  $ hg add a
  $ hg pull -u ../a
  pulling from ../a
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg st

  $ cd ..