view tests/test-up-local-change.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

  $ 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
    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
   a: versions differ -> m (premerge)
  picked tool 'true' for a (binary False symlink False changedelete False)
  merging a
  my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
   a: versions differ -> m (merge)
  picked tool 'true' for a (binary False symlink False changedelete False)
  my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
  launching merge tool: true *$TESTTMP/r2/a* * * (glob)
  merge tool returned: 0
  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
  starting 4 threads for background file closing (?)
  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
  starting 4 threads for background file closing (?)
   a: versions differ -> m (premerge)
  picked tool 'true' for a (binary False symlink False changedelete False)
  merging a
  my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb
   a: versions differ -> m (merge)
  picked tool 'true' for a (binary False symlink False changedelete False)
  my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb
  launching merge tool: true *$TESTTMP/r2/a* * * (glob)
  merge tool returned: 0
  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 up
    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
   a: versions differ -> m (premerge)
  picked tool 'true' for a (binary False symlink False changedelete False)
  merging a
  my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
   a: versions differ -> m (merge)
  picked tool 'true' for a (binary False symlink False changedelete False)
  my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
  launching merge tool: true *$TESTTMP/r2/a* * * (glob)
  merge tool returned: 0
  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
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updated to "1e71731e6fbb: 2"
  1 other heads for branch "default"

test conflicting untracked files

  $ hg up -qC 0
  $ echo untracked > b
  $ hg st
  ? b
  $ hg up 1
  b: untracked file differs
  abort: untracked files in working directory differ from files in requested revision
  [255]
  $ rm b

test conflicting untracked ignored file

  $ hg up -qC 0
  $ echo ignored > .hgignore
  $ hg add .hgignore
  $ hg ci -m 'add .hgignore'
  created new head
  $ echo ignored > ignored
  $ hg add ignored
  $ hg ci -m 'add ignored file'

  $ hg up -q 'desc("add .hgignore")'
  $ echo untracked > ignored
  $ hg st
  $ hg up 'desc("add ignored file")'
  ignored: untracked file differs
  abort: untracked files in working directory differ from files in requested revision
  [255]

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
  new changesets cb9a9f314b8b
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg st

test updating backwards through a rename

  $ hg mv a b
  $ hg ci -m b
  $ echo b > b
  $ hg up -q 0
  $ hg st
  M a
  $ hg diff --nodates
  diff -r cb9a9f314b8b a
  --- a/a
  +++ b/a
  @@ -1,1 +1,1 @@
  -a
  +b

test for superfluous filemerge of clean files renamed in the past

  $ hg up -qC tip
  $ echo c > c
  $ hg add c
  $ hg up -qt:fail 0

  $ cd ..