view tests/test-githelp.t @ 44363:f7459da77f23

nodemap: introduce an option to use mmap to read the nodemap mapping

The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.

This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).

Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:

Before:

 * do not use the persistent nodemap
 * use the CPython implementation of the index for nodemap
 * use mmapping of the changelog index

After:

 * use the MixedIndex Rust code, with the NodeTree object for nodemap access
   (still in review)
 * use the persistent nodemap data from disk
 * access the persistent nodemap data through mmap
 * use mmapping of the changelog index

The persistent nodemap greatly speed up  most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.

Here are some numbers (in seconds) for the reference copy of mozilla-try:

Revset            Before   After     abs-change speedup

-10000:           0.004622 0.005532   0.000910  ×   0.83
-10:              0.000050 0.000132   0.000082  ×   0.37
tip               0.000052 0.000085   0.000033  ×   0.61
0 + (-10000:)     0.028222 0.005337  -0.022885  ×   5.29
0                 0.023521 0.000084  -0.023437  × 280.01
(-10000:) + 0     0.235539 0.005308  -0.230231  ×  44.37
(-10:) + :9       0.232883 0.000180  -0.232703  ×1293.79
(-10000:) + (:99) 0.238735 0.005358  -0.233377  ×  44.55
:99 + (-10000:)   0.317942 0.005593  -0.312349  ×  56.84
:9 + (-10:)       0.313372 0.000179  -0.313193  ×1750.68
:9                0.316450 0.000143  -0.316307  ×2212.93


On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.

Here are some numbers (in seconds) for the reference copy of mercurial:

Revset            Before   After     abs-change speedup
-10:              0.000065 0.000097   0.000032  × 0.67
tip               0.000063 0.000078   0.000015  × 0.80
0                 0.000561 0.000079  -0.000482  × 7.10
-10000:           0.004609 0.003648  -0.000961  × 1.26
0 + (-10000:)     0.005023 0.003715  -0.001307  × 1.35
(-10:) + :9       0.002187 0.000108  -0.002079  ×20.25
(-10000:) + 0     0.006252 0.003716  -0.002536  × 1.68
(-10000:) + (:99) 0.006367 0.003707  -0.002660  × 1.71
:9 + (-10:)       0.003846 0.000110  -0.003736  ×34.96
:9                0.003854 0.000099  -0.003755  ×38.92
:99 + (-10000:)   0.007644 0.003778  -0.003866  × 2.02

Differential Revision: https://phab.mercurial-scm.org/D7894

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

  $ hg init repo
  $ cd repo
  $ echo foo > test_file
  $ mkdir dir
  $ echo foo > dir/file
  $ echo foo > removed_file
  $ echo foo > deleted_file
  $ hg add -q .
  $ hg commit -m 'bar'
  $ hg bookmark both
  $ touch both
  $ touch untracked_file
  $ hg remove removed_file
  $ rm deleted_file

githelp on a single command should succeed
  $ hg githelp -- commit
  hg commit
  $ hg githelp -- git commit
  hg commit

githelp should fail nicely if we don't give it arguments
  $ hg githelp
  abort: missing git command - usage: hg githelp -- <git command>
  [255]
  $ hg githelp -- git
  abort: missing git command - usage: hg githelp -- <git command>
  [255]

githelp on a command with options should succeed
  $ hg githelp -- commit -pm "abc"
  hg commit --interactive -m 'abc'

githelp on a command with standalone unrecognized option should succeed with warning
  $ hg githelp -- commit -p -v
  ignoring unknown option -v
  hg commit --interactive

githelp on a command with unrecognized option packed with other options should fail with error
  $ hg githelp -- commit -pv
  abort: unknown option 'v' packed with other options
  (please try passing the option as its own flag: -v)
  [255]

githelp for git rebase --skip
  $ hg githelp -- git rebase --skip
  hg revert --all -r .
  hg rebase --continue

githelp for git commit --amend (hg commit --amend pulls up an editor)
  $ hg githelp -- commit --amend
  hg commit --amend

githelp for git commit --amend --no-edit (hg amend does not pull up an editor)
  $ hg githelp -- commit --amend --no-edit
  hg amend

githelp for git checkout -- . (checking out a directory)
  $ hg githelp -- checkout -- .
  note: use --no-backup to avoid creating .orig files
  
  hg revert .

githelp for git checkout "HEAD^" (should still work to pass a rev)
  $ hg githelp -- checkout "HEAD^"
  hg update .^

githelp checkout: args after -- should be treated as paths no matter what
  $ hg githelp -- checkout -- HEAD
  note: use --no-backup to avoid creating .orig files
  
  hg revert HEAD

githelp for git checkout with rev and path
  $ hg githelp -- checkout "HEAD^" -- file.txt
  note: use --no-backup to avoid creating .orig files
  
  hg revert -r .^ file.txt

githelp for git with rev and path, without separator
  $ hg githelp -- checkout "HEAD^" file.txt
  note: use --no-backup to avoid creating .orig files
  
  hg revert -r .^ file.txt

githelp for checkout with a file as first argument
  $ hg githelp -- checkout test_file
  note: use --no-backup to avoid creating .orig files
  
  hg revert test_file

githelp for checkout with a removed file as first argument
  $ hg githelp -- checkout removed_file
  note: use --no-backup to avoid creating .orig files
  
  hg revert removed_file

githelp for checkout with a deleted file as first argument
  $ hg githelp -- checkout deleted_file
  note: use --no-backup to avoid creating .orig files
  
  hg revert deleted_file

githelp for checkout with a untracked file as first argument
  $ hg githelp -- checkout untracked_file
  note: use --no-backup to avoid creating .orig files
  
  hg revert untracked_file

githelp for checkout with a directory as first argument
  $ hg githelp -- checkout dir
  note: use --no-backup to avoid creating .orig files
  
  hg revert dir

githelp for checkout when not in repo root
  $ cd dir
  $ hg githelp -- checkout file
  note: use --no-backup to avoid creating .orig files
  
  hg revert file

  $ cd ..

githelp for checkout with an argument that is both a file and a revision
  $ hg githelp -- checkout both
  hg update both

githelp for checkout with the -p option
  $ hg githelp -- git checkout -p xyz
  hg revert -i -r xyz

  $ hg githelp -- git checkout -p xyz -- abc
  note: use --no-backup to avoid creating .orig files
  
  hg revert -i -r xyz abc

githelp for checkout with the -f option and a rev
  $ hg githelp -- git checkout -f xyz
  hg update -C xyz
  $ hg githelp -- git checkout --force xyz
  hg update -C xyz

githelp for checkout with the -f option without an arg
  $ hg githelp -- git checkout -f
  hg revert --all
  $ hg githelp -- git checkout --force
  hg revert --all

githelp for grep with pattern and path
  $ hg githelp -- grep shrubbery flib/intern/
  hg grep shrubbery flib/intern/

githelp for reset, checking ~ in git becomes ~1 in mercurial
  $ hg githelp -- reset HEAD~
  hg update .~1
  $ hg githelp -- reset "HEAD^"
  hg update .^
  $ hg githelp -- reset HEAD~3
  hg update .~3

  $ hg githelp -- reset --mixed HEAD
  note: --mixed has no meaning since Mercurial has no staging area
  
  hg update .
  $ hg githelp -- reset --soft HEAD
  note: --soft has no meaning since Mercurial has no staging area
  
  hg update .
  $ hg githelp -- reset --hard HEAD
  hg update --clean .

githelp for git show --name-status
  $ hg githelp -- git show --name-status
  hg log --style status -r .

githelp for git show --pretty=format: --name-status
  $ hg githelp -- git show --pretty=format: --name-status
  hg status --change .

githelp for show with no arguments
  $ hg githelp -- show
  hg export

githelp for show with a path
  $ hg githelp -- show test_file
  hg cat test_file

githelp for show with not a path:
  $ hg githelp -- show rev
  hg export rev

githelp for show with many arguments
  $ hg githelp -- show argone argtwo
  hg export argone argtwo
  $ hg githelp -- show test_file argone argtwo
  hg cat test_file argone argtwo

githelp for show with --unified options
  $ hg githelp -- show --unified=10
  hg export --config diff.unified=10
  $ hg githelp -- show -U100
  hg export --config diff.unified=100

githelp for show with a path and --unified
  $ hg githelp -- show -U20 test_file
  hg cat test_file --config diff.unified=20

githelp for stash drop without name
  $ hg githelp -- git stash drop
  hg shelve -d <shelve name>

githelp for stash drop with name
  $ hg githelp -- git stash drop xyz
  hg shelve -d xyz

githelp for stash list with patch
  $ hg githelp -- git stash list -p
  hg shelve -l -p

githelp for stash show
  $ hg githelp -- git stash show
  hg shelve --stat

githelp for stash show with patch and name
  $ hg githelp -- git stash show -p mystash
  hg shelve -p mystash

githelp for stash clear
  $ hg githelp -- git stash clear
  hg shelve --cleanup

githelp for whatchanged should show deprecated message
  $ hg githelp -- whatchanged -p
  this command has been deprecated in the git project, thus isn't supported by this tool
  

githelp for git branch -m renaming
  $ hg githelp -- git branch -m old new
  hg bookmark -m old new

When the old name is omitted, git branch -m new renames the current branch.
  $ hg githelp -- git branch -m new
  hg bookmark -m `hg log -T"{activebookmark}" -r .` new

Branch deletion in git strips commits
  $ hg githelp -- git branch -d
  hg strip -B
  $ hg githelp -- git branch -d feature
  hg strip -B feature -B
  $ hg githelp -- git branch --delete experiment1 experiment2
  hg strip -B experiment1 -B experiment2 -B

githelp for reuse message using the shorthand
  $ hg githelp -- git commit -C deadbeef
  hg commit -M deadbeef

githelp for reuse message using the the long version
  $ hg githelp -- git commit --reuse-message deadbeef
  hg commit -M deadbeef

githelp for reuse message using HEAD
  $ hg githelp -- git commit --reuse-message HEAD~
  hg commit -M .~1

githelp for apply with no options
  $ hg githelp -- apply
  hg import --no-commit

githelp for apply with directory strip custom
  $ hg githelp -- apply -p 5
  hg import --no-commit -p 5

githelp for apply with prefix directory
  $ hg githelp -- apply --directory=modules
  hg import --no-commit --prefix modules

git merge-base
  $ hg githelp -- git merge-base --is-ancestor
  ignoring unknown option --is-ancestor
  note: ancestors() is part of the revset language
  (learn more about revsets with 'hg help revsets')
  
  hg log -T '{node}\n' -r 'ancestor(A,B)'

githelp for git blame
  $ hg githelp -- git blame
  hg annotate -udl

githelp for add

  $ hg githelp -- git add
  hg add

  $ hg githelp -- git add -p
  note: Mercurial will commit when complete, as there is no staging area in Mercurial
  
  hg commit --interactive

  $ hg githelp -- git add --all
  note: use hg addremove to remove files that have been deleted
  
  hg add

githelp for reflog

  $ hg githelp -- git reflog
  hg journal
  
  note: in hg commits can be deleted from repo but we always have backups

  $ hg githelp -- git reflog --all
  hg journal --all
  
  note: in hg commits can be deleted from repo but we always have backups