tests/test-uncommit.t

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

Test uncommit - set up the config

  $ cat >> $HGRCPATH <<EOF
  > [experimental]
  > evolution.createmarkers=True
  > evolution.allowunstable=True
  > [extensions]
  > uncommit =
  > drawdag=$TESTDIR/drawdag.py
  > EOF

Build up a repo

  $ hg init repo
  $ cd repo
  $ hg bookmark foo

Help for uncommit

  $ hg help uncommit
  hg uncommit [OPTION]... [FILE]...
  
  uncommit part or all of a local changeset
  
      This command undoes the effect of a local commit, returning the affected
      files to their uncommitted state. This means that files modified or
      deleted in the changeset will be left unchanged, and so will remain
      modified in the working directory.
  
      If no files are specified, the commit will be pruned, unless --keep is
      given.
  
  (use 'hg help -e uncommit' to show help for the uncommit extension)
  
  options ([+] can be repeated):
  
      --keep                     allow an empty commit after uncommiting
      --allow-dirty-working-copy allow uncommit with outstanding changes
   -I --include PATTERN [+]      include names matching the given patterns
   -X --exclude PATTERN [+]      exclude names matching the given patterns
  
  (some details hidden, use --verbose to show complete help)

Uncommit with no commits should fail

  $ hg uncommit
  abort: cannot uncommit null changeset
  (no changeset checked out)
  [255]

Create some commits

  $ touch files
  $ hg add files
  $ for i in a ab abc abcd abcde; do echo $i > files; echo $i > file-$i; hg add file-$i; hg commit -m "added file-$i"; done
  $ ls
  file-a
  file-ab
  file-abc
  file-abcd
  file-abcde
  files

  $ hg log -G -T '{rev}:{node} {desc}' --hidden
  @  4:6c4fd43ed714e7fcd8adbaa7b16c953c2e985b60 added file-abcde
  |
  o  3:6db330d65db434145c0b59d291853e9a84719b24 added file-abcd
  |
  o  2:abf2df566fc193b3ac34d946e63c1583e4d4732b added file-abc
  |
  o  1:69a232e754b08d568c4899475faf2eb44b857802 added file-ab
  |
  o  0:3004d2d9b50883c1538fc754a3aeb55f1b4084f6 added file-a
  
Simple uncommit off the top, also moves bookmark

  $ hg bookmark
   * foo                       4:6c4fd43ed714
  $ hg uncommit
  $ hg status
  M files
  A file-abcde
  $ hg bookmark
   * foo                       3:6db330d65db4

  $ hg log -G -T '{rev}:{node} {desc}' --hidden
  x  4:6c4fd43ed714e7fcd8adbaa7b16c953c2e985b60 added file-abcde
  |
  @  3:6db330d65db434145c0b59d291853e9a84719b24 added file-abcd
  |
  o  2:abf2df566fc193b3ac34d946e63c1583e4d4732b added file-abc
  |
  o  1:69a232e754b08d568c4899475faf2eb44b857802 added file-ab
  |
  o  0:3004d2d9b50883c1538fc754a3aeb55f1b4084f6 added file-a
  

Recommit

  $ hg commit -m 'new change abcde'
  $ hg status
  $ hg heads -T '{rev}:{node} {desc}'
  5:0c07a3ccda771b25f1cb1edbd02e683723344ef1 new change abcde (no-eol)

Uncommit of non-existent and unchanged files aborts
  $ hg uncommit nothinghere
  abort: cannot uncommit "nothinghere"
  (file does not exist)
  [255]
  $ hg status
  $ hg uncommit file-abc
  abort: cannot uncommit "file-abc"
  (file was not changed in working directory parent)
  [255]
  $ hg status

Try partial uncommit, also moves bookmark

  $ hg bookmark
   * foo                       5:0c07a3ccda77
  $ hg uncommit files
  $ hg status
  M files
  $ hg bookmark
   * foo                       6:3727deee06f7
  $ hg heads -T '{rev}:{node} {desc}'
  6:3727deee06f72f5ffa8db792ee299cf39e3e190b new change abcde (no-eol)
  $ hg log -r . -p -T '{rev}:{node} {desc}'
  6:3727deee06f72f5ffa8db792ee299cf39e3e190b new change abcdediff -r 6db330d65db4 -r 3727deee06f7 file-abcde
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file-abcde	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +abcde
  
  $ hg log -G -T '{rev}:{node} {desc}' --hidden
  @  6:3727deee06f72f5ffa8db792ee299cf39e3e190b new change abcde
  |
  | x  5:0c07a3ccda771b25f1cb1edbd02e683723344ef1 new change abcde
  |/
  | x  4:6c4fd43ed714e7fcd8adbaa7b16c953c2e985b60 added file-abcde
  |/
  o  3:6db330d65db434145c0b59d291853e9a84719b24 added file-abcd
  |
  o  2:abf2df566fc193b3ac34d946e63c1583e4d4732b added file-abc
  |
  o  1:69a232e754b08d568c4899475faf2eb44b857802 added file-ab
  |
  o  0:3004d2d9b50883c1538fc754a3aeb55f1b4084f6 added file-a
  
  $ hg commit -m 'update files for abcde'

Uncommit with dirty state

  $ echo "foo" >> files
  $ cat files
  abcde
  foo
  $ hg status
  M files
  $ hg uncommit
  abort: uncommitted changes
  (requires --allow-dirty-working-copy to uncommit)
  [255]
  $ hg uncommit files
  abort: uncommitted changes
  (requires --allow-dirty-working-copy to uncommit)
  [255]
  $ cat files
  abcde
  foo
  $ hg commit --amend -m "files abcde + foo"

Testing the 'experimental.uncommitondirtywdir' config

  $ echo "bar" >> files
  $ hg uncommit
  abort: uncommitted changes
  (requires --allow-dirty-working-copy to uncommit)
  [255]
  $ hg uncommit --config experimental.uncommitondirtywdir=True
  $ hg commit -m "files abcde + foo"

Uncommit in the middle of a stack, does not move bookmark

  $ hg checkout '.^^^'
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved
  (leaving bookmark foo)
  $ hg log -r . -p -T '{rev}:{node} {desc}'
  2:abf2df566fc193b3ac34d946e63c1583e4d4732b added file-abcdiff -r 69a232e754b0 -r abf2df566fc1 file-abc
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file-abc	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +abc
  diff -r 69a232e754b0 -r abf2df566fc1 files
  --- a/files	Thu Jan 01 00:00:00 1970 +0000
  +++ b/files	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -ab
  +abc
  
  $ hg bookmark
     foo                       9:48e5bd7cd583
  $ hg uncommit
  3 new orphan changesets
  $ hg status
  M files
  A file-abc
  $ hg heads -T '{rev}:{node} {desc}'
  9:48e5bd7cd583eb24164ef8b89185819c84c96ed7 files abcde + foo (no-eol)
  $ hg bookmark
     foo                       9:48e5bd7cd583
  $ hg commit -m 'new abc'
  created new head

Partial uncommit in the middle, does not move bookmark

  $ hg checkout '.^'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg log -r . -p -T '{rev}:{node} {desc}'
  1:69a232e754b08d568c4899475faf2eb44b857802 added file-abdiff -r 3004d2d9b508 -r 69a232e754b0 file-ab
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file-ab	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +ab
  diff -r 3004d2d9b508 -r 69a232e754b0 files
  --- a/files	Thu Jan 01 00:00:00 1970 +0000
  +++ b/files	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -a
  +ab
  
  $ hg bookmark
     foo                       9:48e5bd7cd583
  $ hg uncommit file-ab
  1 new orphan changesets
  $ hg status
  A file-ab

  $ hg heads -T '{rev}:{node} {desc}\n'
  11:8eb87968f2edb7f27f27fe676316e179de65fff6 added file-ab
  10:5dc89ca4486f8a88716c5797fa9f498d13d7c2e1 new abc
  9:48e5bd7cd583eb24164ef8b89185819c84c96ed7 files abcde + foo

  $ hg bookmark
     foo                       9:48e5bd7cd583
  $ hg commit -m 'update ab'
  $ hg status
  $ hg heads -T '{rev}:{node} {desc}\n'
  12:f21039c59242b085491bb58f591afc4ed1c04c09 update ab
  10:5dc89ca4486f8a88716c5797fa9f498d13d7c2e1 new abc
  9:48e5bd7cd583eb24164ef8b89185819c84c96ed7 files abcde + foo

  $ hg log -G -T '{rev}:{node} {desc}' --hidden
  @  12:f21039c59242b085491bb58f591afc4ed1c04c09 update ab
  |
  o  11:8eb87968f2edb7f27f27fe676316e179de65fff6 added file-ab
  |
  | *  10:5dc89ca4486f8a88716c5797fa9f498d13d7c2e1 new abc
  | |
  | | *  9:48e5bd7cd583eb24164ef8b89185819c84c96ed7 files abcde + foo
  | | |
  | | | x  8:84beeba0ac30e19521c036e4d2dd3a5fa02586ff files abcde + foo
  | | |/
  | | | x  7:0977fa602c2fd7d8427ed4e7ee15ea13b84c9173 update files for abcde
  | | |/
  | | *  6:3727deee06f72f5ffa8db792ee299cf39e3e190b new change abcde
  | | |
  | | | x  5:0c07a3ccda771b25f1cb1edbd02e683723344ef1 new change abcde
  | | |/
  | | | x  4:6c4fd43ed714e7fcd8adbaa7b16c953c2e985b60 added file-abcde
  | | |/
  | | *  3:6db330d65db434145c0b59d291853e9a84719b24 added file-abcd
  | | |
  | | x  2:abf2df566fc193b3ac34d946e63c1583e4d4732b added file-abc
  | |/
  | x  1:69a232e754b08d568c4899475faf2eb44b857802 added file-ab
  |/
  o  0:3004d2d9b50883c1538fc754a3aeb55f1b4084f6 added file-a
  
Uncommit with draft parent

  $ hg uncommit
  $ hg phase -r .
  11: draft
  $ hg commit -m 'update ab again'

Phase is preserved

  $ hg uncommit --keep --config phases.new-commit=secret
  note: keeping empty commit
  $ hg phase -r .
  14: draft
  $ hg commit --amend -m 'update ab again'

Uncommit with public parent

  $ hg phase -p "::.^"
  $ hg uncommit
  $ hg phase -r .
  11: public

Partial uncommit with public parent

  $ echo xyz > xyz
  $ hg add xyz
  $ hg commit -m "update ab and add xyz"
  $ hg uncommit xyz
  $ hg status
  A xyz
  $ hg phase -r .
  17: draft
  $ hg phase -r ".^"
  11: public

Uncommit with --keep or experimental.uncommit.keep leaves an empty changeset

  $ cd $TESTTMP
  $ hg init repo1
  $ cd repo1
  $ hg debugdrawdag <<'EOS'
  > Q
  > |
  > P
  > EOS
  $ hg up Q -q
  $ hg uncommit --keep
  note: keeping empty commit
  $ hg log -G -T '{desc} FILES: {files}'
  @  Q FILES:
  |
  | x  Q FILES: Q
  |/
  o  P FILES: P
  
  $ cat >> .hg/hgrc <<EOF
  > [experimental]
  > uncommit.keep=True
  > EOF
  $ hg ci --amend
  $ hg uncommit
  note: keeping empty commit
  $ hg log -G -T '{desc} FILES: {files}'
  @  Q FILES:
  |
  | x  Q FILES: Q
  |/
  o  P FILES: P
  
  $ hg status
  A Q
  $ hg ci --amend
  $ hg uncommit --no-keep
  $ hg log -G -T '{desc} FILES: {files}'
  x  Q FILES: Q
  |
  @  P FILES: P
  
  $ hg status
  A Q
  $ cd ..
  $ rm -rf repo1

Testing uncommit while merge

  $ hg init repo2
  $ cd repo2

Create some history

  $ touch a
  $ hg add a
  $ for i in 1 2 3; do echo $i > a; hg commit -m "a $i"; done
  $ hg checkout 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ touch b
  $ hg add b
  $ for i in 1 2 3; do echo $i > b; hg commit -m "b $i"; done
  created new head
  $ hg log -G -T '{rev}:{node} {desc}' --hidden
  @  5:2cd56cdde163ded2fbb16ba2f918c96046ab0bf2 b 3
  |
  o  4:c3a0d5bb3b15834ffd2ef9ef603e93ec65cf2037 b 2
  |
  o  3:49bb009ca26078726b8870f1edb29fae8f7618f5 b 1
  |
  | o  2:990982b7384266e691f1bc08ca36177adcd1c8a9 a 3
  | |
  | o  1:24d38e3cf160c7b6f5ffe82179332229886a6d34 a 2
  |/
  o  0:ea4e33293d4d274a2ba73150733c2612231f398c a 1
  

Add and expect uncommit to fail on both merge working dir and merge changeset

  $ hg merge 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ hg uncommit
  abort: outstanding uncommitted merge
  (requires --allow-dirty-working-copy to uncommit)
  [255]

  $ hg uncommit --config experimental.uncommitondirtywdir=True
  abort: cannot uncommit while merging
  [255]

  $ hg status
  M a
  $ hg commit -m 'merge a and b'

  $ hg uncommit
  abort: cannot uncommit merge changeset
  [255]

  $ hg status
  $ hg log -G -T '{rev}:{node} {desc}' --hidden
  @    6:c03b9c37bc67bf504d4912061cfb527b47a63c6e merge a and b
  |\
  | o  5:2cd56cdde163ded2fbb16ba2f918c96046ab0bf2 b 3
  | |
  | o  4:c3a0d5bb3b15834ffd2ef9ef603e93ec65cf2037 b 2
  | |
  | o  3:49bb009ca26078726b8870f1edb29fae8f7618f5 b 1
  | |
  o |  2:990982b7384266e691f1bc08ca36177adcd1c8a9 a 3
  | |
  o |  1:24d38e3cf160c7b6f5ffe82179332229886a6d34 a 2
  |/
  o  0:ea4e33293d4d274a2ba73150733c2612231f398c a 1
  

Rename a->b, then remove b in working copy. Result should remove a.

  $ hg co -q 0
  $ hg mv a b
  $ hg ci -qm 'move a to b'
  $ hg rm b
  $ hg uncommit --config experimental.uncommitondirtywdir=True
  $ hg st --copies
  R a
  $ hg revert a

Rename a->b, then rename b->c in working copy. Result should rename a->c.

  $ hg co -q 0
  $ hg mv a b
  $ hg ci -qm 'move a to b'
  $ hg mv b c
  $ hg uncommit --config experimental.uncommitondirtywdir=True
  $ hg st --copies
  A c
    a
  R a
  $ hg revert a
  $ hg forget c
  $ rm c

Copy a->b1 and a->b2, then rename b1->c in working copy. Result should copy a->b2 and a->c.

  $ hg co -q 0
  $ hg cp a b1
  $ hg cp a b2
  $ hg ci -qm 'move a to b1 and b2'
  $ hg mv b1 c
  $ hg uncommit --config experimental.uncommitondirtywdir=True
  $ hg st --copies
  A b2
    a
  A c
    a
  $ cd ..

--allow-dirty-working-copy should also work on a dirty PATH

  $ hg init issue5977
  $ cd issue5977
  $ echo 'super critical info!' > a
  $ hg ci -Am 'add a'
  adding a
  $ echo 'foo' > b
  $ hg add b
  $ hg status
  A b
  $ hg unc a
  note: keeping empty commit
  $ cat a
  super critical info!
  $ hg log
  changeset:   1:656ba143d384
  tag:         tip
  parent:      -1:000000000000
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     add a
  
  $ hg ci -Am 'add b'
  $ echo 'foo bar' > b
  $ hg unc b
  abort: uncommitted changes
  (requires --allow-dirty-working-copy to uncommit)
  [255]
  $ hg unc --allow-dirty-working-copy b
  $ hg log
  changeset:   3:30fa958635b2
  tag:         tip
  parent:      1:656ba143d384
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     add b
  
  changeset:   1:656ba143d384
  parent:      -1:000000000000
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     add a
  
Removes can be uncommitted

  $ hg ci -m 'modified b'
  $ hg rm b
  $ hg ci -m 'remove b'
  $ hg uncommit b
  note: keeping empty commit
  $ hg status
  R b

Uncommitting a directory won't run afoul of the checks that an explicit file
can be uncommitted.

  $ mkdir dir
  $ echo 1 > dir/file.txt
  $ hg ci -Aqm 'add file in directory'
  $ hg uncommit dir
  $ hg status
  A dir/file.txt

`uncommit <dir>` and `cd <dir> && uncommit .` behave the same...

  $ hg rollback -q --config ui.rollback=True
  $ echo 2 > dir/file2.txt
  $ hg ci -Aqm 'add file2 in directory'
  $ hg uncommit dir
  note: keeping empty commit
  $ hg status
  A dir/file2.txt

  $ hg rollback -q --config ui.rollback=True
  $ cd dir
  $ hg uncommit .
  note: keeping empty commit
  $ hg status
  A dir/file2.txt
  $ cd ..

... and errors out the same way when nothing can be uncommitted

  $ hg rollback -q --config ui.rollback=True
  $ mkdir emptydir
  $ hg uncommit emptydir
  abort: cannot uncommit "emptydir"
  (file was untracked in working directory parent)
  [255]

  $ cd emptydir
  $ hg uncommit .
  abort: cannot uncommit "emptydir"
  (file was untracked in working directory parent)
  [255]
  $ hg status
  $ cd ..