view tests/test-githelp.t @ 42621:99ebde4fec99

commit: improve the files field of changelog for merges

Currently, the files list of merge commits repeats all the deletions
(either actual deletions, or files that got renamed) that happened
between base and p2 of the merge. If p2 is the main branch, the list
can easily be much bigger than the change being merged.

This results in various problems worth improving:
- changelog is bigger than necessary
- `hg log directory` lists many unrelated merge commits, and `hg log
  -v -r commit` frequently fills multiple screens worth of files
- it possibly slows down adjustlinkrev, by forcing it to read more
  manifests, and that function can certainly be a bottleneck
- the server side of pulls can waste a lot of time simply opening the
  filelogs for pointless files (the constant factors for opening even
  a tiny filelog is apparently pretty bad)

So stop listing such files as described in the code.  Impacted merge
commits and their descendants get a different hash than they would
have without this. This doesn't seem problematic, except for
convert. The previous commit helped with that in the hg->hg case (but
if you do svn->hg twice from scratch, hashes can still change).

The rest of the description is numbers. I don't have much to report,
because recreating the files list of existing repositories is not
easy:
- debugupgradeformat and bundle/unbundle don't recreate the list
- export/import tends to choke quickly applying patches or on
  description that contain diffs,
- merge commits from the convert extension don't have the right files
  list for reasons orthogonal to the current commit
- replaying the merge with hg update/hg merge/hg revert --all/hg
  commit can end up failing in hg revert
- I wasn't sure that using debugsetparents + debugrebuilddirstate
  would really build the right thing

I measured commit time before and after this change, in a case with no
files filtered out, several files filtered out (no difference) and 5k
files filtered out (+1% time).

Recreating the 100 more recent merges in a private repo, the
concatenated uncompressed files lists goes from 1.12MB to
0.52MB. Excluding 3 merges that are not representative, then the size
goes from 570k to 15k.
I converted part of mozilla-central, and observed file list shrinking
quite a bit too, starting at the very first merge, 733641d9feaf, going
from 550 files to 10 files (although they have relatively few merges,
so they probably wouldn't care).

Differential Revision: https://phab.mercurial-scm.org/D6613

  $ 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 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