annotate tests/test-commit-amend.t @ 30442:41a8106789ca

util: implement zstd compression engine

Now that zstd is vendored and being built (in some configurations), we
can implement a compression engine for zstd!

The zstd engine is a little different from existing engines. Because
it may not always be present, we have to defer load the module in case
importing it fails. We facilitate this via a cached property that holds
a reference to the module or None. The "available" method is
implemented to reflect reality.

The zstd engine declares its ability to handle bundles using the
"zstd" human name and the "ZS" internal name. The latter was chosen
because internal names are 2 characters (by only convention I think)
and "ZS" seems reasonable.

The engine, like others, supports specifying the compression level.
However, there are no consumers of this API that yet pass in that
argument. I have plans to change that, so stay tuned.

Since all we need to do to support bundle generation with a new
compression engine is implement and register the compression engine,
bundle generation with zstd "just works!" Tests demonstrating this
have been added.

How does performance of zstd for bundle generation compare? On the
mozilla-unified repo, `hg bundle --all -t <engine>-v2` yields the
following on my i7-6700K on Linux:

engine        CPU time     bundle size   vs orig size   throughput
none            97.0s     4,054,405,584     100.0%       41.8 MB/s
bzip2 (l=9)    393.6s       975,343,098      24.0%       10.3 MB/s
gzip (l=6)     184.0s     1,140,533,074      28.1%       22.0 MB/s
zstd (l=1)     108.2s     1,119,434,718      27.6%       37.5 MB/s
zstd (l=2)     111.3s     1,078,328,002      26.6%       36.4 MB/s
zstd (l=3)     113.7s     1,011,823,727      25.0%       35.7 MB/s
zstd (l=4)     116.0s     1,008,965,888      24.9%       35.0 MB/s
zstd (l=5)     121.0s       977,203,148      24.1%       33.5 MB/s
zstd (l=6)     131.7s       927,360,198      22.9%       30.8 MB/s
zstd (l=7)     139.0s       912,808,505      22.5%       29.2 MB/s
zstd (l=12)    198.1s       854,527,714      21.1%       20.5 MB/s
zstd (l=18)    681.6s       789,750,690      19.5%        5.9 MB/s

On compression, zstd for bundle generation delivers:

* better compression than gzip with significantly less CPU utilization
* better than bzip2 compression ratios while still being significantly
  faster than gzip
* ability to aggressively tune compression level to achieve
  significantly smaller bundles

That last point is important. With clone bundles, a server can
pre-generate a bundle file, upload it to a static file server, and
redirect clients to transparently download it during clone. The server
could choose to produce a zstd bundle with the highest compression
settings possible. This would take a very long time - a magnitude
longer than a typical zstd bundle generation - but the result would
be hundreds of megabytes smaller! For the clone volume we do at
Mozilla, this could translate to petabytes of bandwidth savings
per year and faster clones (due to smaller transfer size).

I don't have detailed numbers to report on decompression. However,
zstd decompression is fast: >1 GB/s output throughput on this machine,
even through the Python bindings. And it can do that regardless of the
compression level of the input. By the time you have enough data to
worry about overhead of decompression, you have plenty of other things
to worry about performance wise.

zstd is wins all around. I can't wait to implement support for it
on the wire protocol and in revlogs.

  $ cat << EOF >> $HGRCPATH
  > [format]
  > usegeneraldelta=yes
  > EOF

  $ hg init

Setup:

  $ echo a >> a
  $ hg ci -Am 'base'
  adding a

Refuse to amend public csets:

  $ hg phase -r . -p
  $ hg ci --amend
  abort: cannot amend public changesets
  [255]
  $ hg phase -r . -f -d

  $ echo a >> a
  $ hg ci -Am 'base1'

Nothing to amend:

  $ hg ci --amend -m 'base1'
  nothing changed
  [1]

  $ cat >> $HGRCPATH <<EOF
  > [hooks]
  > pretxncommit.foo = sh -c "echo \\"pretxncommit \$HG_NODE\\"; hg id -r \$HG_NODE"
  > EOF

Amending changeset with changes in working dir:
(and check that --message does not trigger an editor)

  $ echo a >> a
  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg commit --amend -m 'amend base1'
  pretxncommit 43f1ba15f28a50abf0aae529cf8a16bfced7b149
  43f1ba15f28a tip
  saved backup bundle to $TESTTMP/.hg/strip-backup/489edb5b847d-f1bf3ab8-amend-backup.hg (glob)
  $ echo 'pretxncommit.foo = ' >> $HGRCPATH
  $ hg diff -c .
  diff -r ad120869acf0 -r 43f1ba15f28a a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,3 @@
   a
  +a
  +a
  $ hg log
  changeset:   1:43f1ba15f28a
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     amend base1
  
  changeset:   0:ad120869acf0
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     base
  

Check proper abort for empty message

  $ cat > editor.sh << '__EOF__'
  > #!/bin/sh
  > echo "" > "$1"
  > __EOF__
  $ echo b > b
  $ hg add b
  $ hg summary
  parent: 1:43f1ba15f28a tip
   amend base1
  branch: default
  commit: 1 added, 1 unknown
  update: (current)
  phases: 2 draft
  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg commit --amend
  transaction abort!
  rollback completed
  abort: empty commit message
  [255]
  $ hg summary
  parent: 1:43f1ba15f28a tip
   amend base1
  branch: default
  commit: 1 added, 1 unknown
  update: (current)
  phases: 2 draft

Add new file:
  $ hg ci --amend -m 'amend base1 new file'
  saved backup bundle to $TESTTMP/.hg/strip-backup/43f1ba15f28a-7a3b3496-amend-backup.hg (glob)

Remove file that was added in amended commit:
(and test logfile option)
(and test that logfile option do not trigger an editor)

  $ hg rm b
  $ echo 'amend base1 remove new file' > ../logfile
  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg ci --amend --logfile ../logfile
  saved backup bundle to $TESTTMP/.hg/strip-backup/b8e3cb2b3882-0b55739a-amend-backup.hg (glob)

  $ hg cat b
  b: no such file in rev 74609c7f506e
  [1]

No changes, just a different message:

  $ hg ci -v --amend -m 'no changes, new message'
  amending changeset 74609c7f506e
  copying changeset 74609c7f506e to ad120869acf0
  committing files:
  a
  committing manifest
  committing changelog
  stripping amended changeset 74609c7f506e
  1 changesets found
  uncompressed size of bundle content:
       254 (changelog)
       163 (manifests)
       129  a
  saved backup bundle to $TESTTMP/.hg/strip-backup/74609c7f506e-1bfde511-amend-backup.hg (glob)
  1 changesets found
  uncompressed size of bundle content:
       250 (changelog)
       163 (manifests)
       129  a
  adding branch
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  committed changeset 1:1cd866679df8
  $ hg diff -c .
  diff -r ad120869acf0 -r 1cd866679df8 a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,3 @@
   a
  +a
  +a
  $ hg log
  changeset:   1:1cd866679df8
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     no changes, new message
  
  changeset:   0:ad120869acf0
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     base
  

Disable default date on commit so when -d isn't given, the old date is preserved:

  $ echo '[defaults]' >> $HGRCPATH
  $ echo 'commit=' >> $HGRCPATH

Test -u/-d:

  $ cat > .hg/checkeditform.sh <<EOF
  > env | grep HGEDITFORM
  > true
  > EOF
  $ HGEDITOR="sh .hg/checkeditform.sh" hg ci --amend -u foo -d '1 0'
  HGEDITFORM=commit.amend.normal
  saved backup bundle to $TESTTMP/.hg/strip-backup/1cd866679df8-5f5bcb85-amend-backup.hg (glob)
  $ echo a >> a
  $ hg ci --amend -u foo -d '1 0'
  saved backup bundle to $TESTTMP/.hg/strip-backup/780e6f23e03d-83b10a27-amend-backup.hg (glob)
  $ hg log -r .
  changeset:   1:5f357c7560ab
  tag:         tip
  user:        foo
  date:        Thu Jan 01 00:00:01 1970 +0000
  summary:     no changes, new message
  

Open editor with old commit message if a message isn't given otherwise:

  $ cat > editor.sh << '__EOF__'
  > #!/bin/sh
  > cat $1
  > echo "another precious commit message" > "$1"
  > __EOF__

at first, test saving last-message.txt

  $ cat > .hg/hgrc << '__EOF__'
  > [hooks]
  > pretxncommit.test-saving-last-message = false
  > __EOF__

  $ rm -f .hg/last-message.txt
  $ hg commit --amend -v -m "message given from command line"
  amending changeset 5f357c7560ab
  copying changeset 5f357c7560ab to ad120869acf0
  committing files:
  a
  committing manifest
  committing changelog
  running hook pretxncommit.test-saving-last-message: false
  transaction abort!
  rollback completed
  abort: pretxncommit.test-saving-last-message hook exited with status 1
  [255]
  $ cat .hg/last-message.txt
  message given from command line (no-eol)

  $ rm -f .hg/last-message.txt
  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg commit --amend -v
  amending changeset 5f357c7560ab
  copying changeset 5f357c7560ab to ad120869acf0
  no changes, new message
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to abort commit.
  HG: --
  HG: user: foo
  HG: branch 'default'
  HG: changed a
  committing files:
  a
  committing manifest
  committing changelog
  running hook pretxncommit.test-saving-last-message: false
  transaction abort!
  rollback completed
  abort: pretxncommit.test-saving-last-message hook exited with status 1
  [255]

  $ cat .hg/last-message.txt
  another precious commit message

  $ cat > .hg/hgrc << '__EOF__'
  > [hooks]
  > pretxncommit.test-saving-last-message =
  > __EOF__

then, test editing custom commit message

  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg commit --amend -v
  amending changeset 5f357c7560ab
  copying changeset 5f357c7560ab to ad120869acf0
  no changes, new message
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to abort commit.
  HG: --
  HG: user: foo
  HG: branch 'default'
  HG: changed a
  committing files:
  a
  committing manifest
  committing changelog
  stripping amended changeset 5f357c7560ab
  1 changesets found
  uncompressed size of bundle content:
       249 (changelog)
       163 (manifests)
       131  a
  saved backup bundle to $TESTTMP/.hg/strip-backup/5f357c7560ab-e7c84ade-amend-backup.hg (glob)
  1 changesets found
  uncompressed size of bundle content:
       257 (changelog)
       163 (manifests)
       131  a
  adding branch
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  committed changeset 1:7ab3bf440b54

Same, but with changes in working dir (different code path):

  $ echo a >> a
  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg commit --amend -v
  amending changeset 7ab3bf440b54
  committing files:
  a
  committing manifest
  committing changelog
  copying changeset a0ea9b1a4c8c to ad120869acf0
  another precious commit message
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to abort commit.
  HG: --
  HG: user: foo
  HG: branch 'default'
  HG: changed a
  committing files:
  a
  committing manifest
  committing changelog
  stripping intermediate changeset a0ea9b1a4c8c
  stripping amended changeset 7ab3bf440b54
  2 changesets found
  uncompressed size of bundle content:
       464 (changelog)
       322 (manifests)
       249  a
  saved backup bundle to $TESTTMP/.hg/strip-backup/7ab3bf440b54-8e3b5088-amend-backup.hg (glob)
  1 changesets found
  uncompressed size of bundle content:
       257 (changelog)
       163 (manifests)
       133  a
  adding branch
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  committed changeset 1:ea22a388757c

  $ rm editor.sh
  $ hg log -r .
  changeset:   1:ea22a388757c
  tag:         tip
  user:        foo
  date:        Thu Jan 01 00:00:01 1970 +0000
  summary:     another precious commit message
  

Moving bookmarks, preserve active bookmark:

  $ hg book book1
  $ hg book book2
  $ hg ci --amend -m 'move bookmarks'
  saved backup bundle to $TESTTMP/.hg/strip-backup/ea22a388757c-e51094db-amend-backup.hg (glob)
  $ hg book
     book1                     1:6cec5aa930e2
   * book2                     1:6cec5aa930e2
  $ echo a >> a
  $ hg ci --amend -m 'move bookmarks'
  saved backup bundle to $TESTTMP/.hg/strip-backup/6cec5aa930e2-e9b06de4-amend-backup.hg (glob)
  $ hg book
     book1                     1:48bb6e53a15f
   * book2                     1:48bb6e53a15f

abort does not loose bookmarks

  $ cat > editor.sh << '__EOF__'
  > #!/bin/sh
  > echo "" > "$1"
  > __EOF__
  $ echo a >> a
  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg commit --amend
  transaction abort!
  rollback completed
  abort: empty commit message
  [255]
  $ hg book
     book1                     1:48bb6e53a15f
   * book2                     1:48bb6e53a15f
  $ hg revert -Caq
  $ rm editor.sh

  $ echo '[defaults]' >> $HGRCPATH
  $ echo "commit=-d '0 0'" >> $HGRCPATH

Moving branches:

  $ hg branch foo
  marked working directory as branch foo
  (branches are permanent and global, did you want a bookmark?)
  $ echo a >> a
  $ hg ci -m 'branch foo'
  $ hg branch default -f
  marked working directory as branch default
  $ hg ci --amend -m 'back to default'
  saved backup bundle to $TESTTMP/.hg/strip-backup/8ac881fbf49d-fd962fef-amend-backup.hg (glob)
  $ hg branches
  default                        2:ce12b0b57d46

Close branch:

  $ hg up -q 0
  $ echo b >> b
  $ hg branch foo
  marked working directory as branch foo
  (branches are permanent and global, did you want a bookmark?)
  $ hg ci -Am 'fork'
  adding b
  $ echo b >> b
  $ hg ci -mb
  $ hg ci --amend --close-branch -m 'closing branch foo'
  saved backup bundle to $TESTTMP/.hg/strip-backup/c962248fa264-6701c392-amend-backup.hg (glob)

Same thing, different code path:

  $ echo b >> b
  $ hg ci -m 'reopen branch'
  reopening closed branch head 4
  $ echo b >> b
  $ hg ci --amend --close-branch
  saved backup bundle to $TESTTMP/.hg/strip-backup/027371728205-49c0c55d-amend-backup.hg (glob)
  $ hg branches
  default                        2:ce12b0b57d46

Refuse to amend during a merge:

  $ hg up -q default
  $ hg merge foo
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci --amend
  abort: cannot amend while merging
  [255]
  $ hg ci -m 'merge'

Follow copies/renames:

  $ hg mv b c
  $ hg ci -m 'b -> c'
  $ hg mv c d
  $ hg ci --amend -m 'b -> d'
  saved backup bundle to $TESTTMP/.hg/strip-backup/b8c6eac7f12e-adaaa8b1-amend-backup.hg (glob)
  $ hg st --rev '.^' --copies d
  A d
    b
  $ hg cp d e
  $ hg ci -m 'e = d'
  $ hg cp e f
  $ hg ci --amend -m 'f = d'
  saved backup bundle to $TESTTMP/.hg/strip-backup/7f9761d65613-d37aa788-amend-backup.hg (glob)
  $ hg st --rev '.^' --copies f
  A f
    d

  $ mv f f.orig
  $ hg rm -A f
  $ hg ci -m removef
  $ hg cp a f
  $ mv f.orig f
  $ hg ci --amend -m replacef
  saved backup bundle to $TESTTMP/.hg/strip-backup/9e8c5f7e3d95-90259f67-amend-backup.hg (glob)
  $ hg st --change . --copies
  $ hg log -r . --template "{file_copies}\n"
  

Move added file (issue3410):

  $ echo g >> g
  $ hg ci -Am g
  adding g
  $ hg mv g h
  $ hg ci --amend
  saved backup bundle to $TESTTMP/.hg/strip-backup/24aa8eacce2b-7059e0f1-amend-backup.hg (glob)
  $ hg st --change . --copies h
  A h
  $ hg log -r . --template "{file_copies}\n"
  

Can't rollback an amend:

  $ hg rollback
  no rollback information available
  [1]

Preserve extra dict (issue3430):

  $ hg branch a
  marked working directory as branch a
  (branches are permanent and global, did you want a bookmark?)
  $ echo a >> a
  $ hg ci -ma
  $ hg ci --amend -m "a'"
  saved backup bundle to $TESTTMP/.hg/strip-backup/3837aa2a2fdb-2be01fd1-amend-backup.hg (glob)
  $ hg log -r . --template "{branch}\n"
  a
  $ hg ci --amend -m "a''"
  saved backup bundle to $TESTTMP/.hg/strip-backup/c05c06be7514-ed28c4cd-amend-backup.hg (glob)
  $ hg log -r . --template "{branch}\n"
  a

Also preserve other entries in the dict that are in the old commit,
first graft something so there's an additional entry:

  $ hg up 0 -q
  $ echo z > z
  $ hg ci -Am 'fork'
  adding z
  created new head
  $ hg up 11
  5 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg graft 12
  grafting 12:2647734878ef "fork" (tip)
  $ hg ci --amend -m 'graft amend'
  saved backup bundle to $TESTTMP/.hg/strip-backup/bd010aea3f39-eedb103b-amend-backup.hg (glob)
  $ hg log -r . --debug | grep extra
  extra:       amend_source=bd010aea3f39f3fb2a2f884b9ccb0471cd77398e
  extra:       branch=a
  extra:       source=2647734878ef0236dda712fae9c1651cf694ea8a

Preserve phase

  $ hg phase '.^::.'
  11: draft
  13: draft
  $ hg phase --secret --force .
  $ hg phase '.^::.'
  11: draft
  13: secret
  $ hg commit --amend -m 'amend for phase' -q
  $ hg phase '.^::.'
  11: draft
  13: secret

Test amend with obsolete
---------------------------

Enable obsolete

  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > evolution=createmarkers,allowunstable
  > EOF

Amend with no files changes

  $ hg id -n
  13
  $ hg ci --amend -m 'babar'
  $ hg id -n
  14
  $ hg log -Gl 3 --style=compact
  @  14[tip]:11   b650e6ee8614   1970-01-01 00:00 +0000   test
  |    babar
  |
  | o  12:0   2647734878ef   1970-01-01 00:00 +0000   test
  | |    fork
  | ~
  o  11   3334b7925910   1970-01-01 00:00 +0000   test
  |    a''
  ~
  $ hg log -Gl 4 --hidden --style=compact
  @  14[tip]:11   b650e6ee8614   1970-01-01 00:00 +0000   test
  |    babar
  |
  | x  13:11   68ff8ff97044   1970-01-01 00:00 +0000   test
  |/     amend for phase
  |
  | o  12:0   2647734878ef   1970-01-01 00:00 +0000   test
  | |    fork
  | ~
  o  11   3334b7925910   1970-01-01 00:00 +0000   test
  |    a''
  ~

Amend with files changes

(note: the extra commit over 15 is a temporary junk I would be happy to get
ride of)

  $ echo 'babar' >> a
  $ hg commit --amend
  $ hg log -Gl 6 --hidden --style=compact
  @  16[tip]:11   9f9e9bccf56c   1970-01-01 00:00 +0000   test
  |    babar
  |
  | x  15   90fef497c56f   1970-01-01 00:00 +0000   test
  | |    temporary amend commit for b650e6ee8614
  | |
  | x  14:11   b650e6ee8614   1970-01-01 00:00 +0000   test
  |/     babar
  |
  | x  13:11   68ff8ff97044   1970-01-01 00:00 +0000   test
  |/     amend for phase
  |
  | o  12:0   2647734878ef   1970-01-01 00:00 +0000   test
  | |    fork
  | ~
  o  11   3334b7925910   1970-01-01 00:00 +0000   test
  |    a''
  ~


Test that amend does not make it easy to create obsolescence cycle
---------------------------------------------------------------------

  $ hg id -r 14 --hidden
  b650e6ee8614 (a)
  $ hg revert -ar 14 --hidden
  reverting a
  $ hg commit --amend
  $ hg id
  b99e5df575f7 (a) tip

Test that rewriting leaving instability behind is allowed
---------------------------------------------------------------------

  $ hg up '.^'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo 'b' >> a
  $ hg log --style compact -r 'children(.)'
  18[tip]:11   b99e5df575f7   1970-01-01 00:00 +0000   test
    babar
  
  $ hg commit --amend
  $ hg log -r 'unstable()'
  changeset:   18:b99e5df575f7
  branch:      a
  parent:      11:3334b7925910
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     babar
  

Amend a merge changeset (with renames and conflicts from the second parent):

  $ hg up -q default
  $ hg branch -q bar
  $ hg cp a aa
  $ hg mv z zz
  $ echo cc > cc
  $ hg add cc
  $ hg ci -m aazzcc
  $ hg up -q default
  $ echo a >> a
  $ echo dd > cc
  $ hg add cc
  $ hg ci -m aa
  $ hg merge -q bar
  warning: conflicts while merging cc! (edit, then use 'hg resolve --mark')
  [1]
  $ hg resolve -m cc
  (no more unresolved files)
  $ hg ci -m 'merge bar'
  $ hg log --config diff.git=1 -pr .
  changeset:   23:69c24fe01e35
  tag:         tip
  parent:      22:30d96aeaf27b
  parent:      21:1aa437659d19
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     merge bar
  
  diff --git a/a b/aa
  copy from a
  copy to aa
  diff --git a/cc b/cc
  --- a/cc
  +++ b/cc
  @@ -1,1 +1,5 @@
  +<<<<<<< working copy: 30d96aeaf27b - test: aa
   dd
  +=======
  +cc
  +>>>>>>> merge rev:    1aa437659d19  bar - test: aazzcc
  diff --git a/z b/zz
  rename from z
  rename to zz
  
  $ hg debugrename aa
  aa renamed from a:a80d06849b333b8a3d5c445f8ba3142010dcdc9e
  $ hg debugrename zz
  zz renamed from z:69a1b67522704ec122181c0890bd16e9d3e7516a
  $ hg debugrename cc
  cc not renamed
  $ HGEDITOR="sh .hg/checkeditform.sh" hg ci --amend -m 'merge bar (amend message)' --edit
  HGEDITFORM=commit.amend.merge
  $ hg log --config diff.git=1 -pr .
  changeset:   24:cfa2fbef3169
  tag:         tip
  parent:      22:30d96aeaf27b
  parent:      21:1aa437659d19
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     merge bar (amend message)
  
  diff --git a/a b/aa
  copy from a
  copy to aa
  diff --git a/cc b/cc
  --- a/cc
  +++ b/cc
  @@ -1,1 +1,5 @@
  +<<<<<<< working copy: 30d96aeaf27b - test: aa
   dd
  +=======
  +cc
  +>>>>>>> merge rev:    1aa437659d19  bar - test: aazzcc
  diff --git a/z b/zz
  rename from z
  rename to zz
  
  $ hg debugrename aa
  aa renamed from a:a80d06849b333b8a3d5c445f8ba3142010dcdc9e
  $ hg debugrename zz
  zz renamed from z:69a1b67522704ec122181c0890bd16e9d3e7516a
  $ hg debugrename cc
  cc not renamed
  $ hg mv zz z
  $ hg ci --amend -m 'merge bar (undo rename)'
  $ hg log --config diff.git=1 -pr .
  changeset:   26:c34de68b014c
  tag:         tip
  parent:      22:30d96aeaf27b
  parent:      21:1aa437659d19
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     merge bar (undo rename)
  
  diff --git a/a b/aa
  copy from a
  copy to aa
  diff --git a/cc b/cc
  --- a/cc
  +++ b/cc
  @@ -1,1 +1,5 @@
  +<<<<<<< working copy: 30d96aeaf27b - test: aa
   dd
  +=======
  +cc
  +>>>>>>> merge rev:    1aa437659d19  bar - test: aazzcc
  
  $ hg debugrename z
  z not renamed

Amend a merge changeset (with renames during the merge):

  $ hg up -q bar
  $ echo x > x
  $ hg add x
  $ hg ci -m x
  $ hg up -q default
  $ hg merge -q bar
  $ hg mv aa aaa
  $ echo aa >> aaa
  $ hg ci -m 'merge bar again'
  $ hg log --config diff.git=1 -pr .
  changeset:   28:37d40dcef03b
  tag:         tip
  parent:      26:c34de68b014c
  parent:      27:4c94d5bc65f5
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     merge bar again
  
  diff --git a/aa b/aa
  deleted file mode 100644
  --- a/aa
  +++ /dev/null
  @@ -1,2 +0,0 @@
  -a
  -a
  diff --git a/aaa b/aaa
  new file mode 100644
  --- /dev/null
  +++ b/aaa
  @@ -0,0 +1,3 @@
  +a
  +a
  +aa
  diff --git a/x b/x
  new file mode 100644
  --- /dev/null
  +++ b/x
  @@ -0,0 +1,1 @@
  +x
  
  $ hg debugrename aaa
  aaa renamed from aa:37d9b5d994eab34eda9c16b195ace52c7b129980
  $ hg mv aaa aa
  $ hg ci --amend -m 'merge bar again (undo rename)'
  $ hg log --config diff.git=1 -pr .
  changeset:   30:537c6d1b3633
  tag:         tip
  parent:      26:c34de68b014c
  parent:      27:4c94d5bc65f5
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     merge bar again (undo rename)
  
  diff --git a/aa b/aa
  --- a/aa
  +++ b/aa
  @@ -1,2 +1,3 @@
   a
   a
  +aa
  diff --git a/x b/x
  new file mode 100644
  --- /dev/null
  +++ b/x
  @@ -0,0 +1,1 @@
  +x
  
  $ hg debugrename aa
  aa not renamed
  $ hg debugrename -r '.^' aa
  aa renamed from a:a80d06849b333b8a3d5c445f8ba3142010dcdc9e

Amend a merge changeset (with manifest-level conflicts):

  $ hg up -q bar
  $ hg rm aa
  $ hg ci -m 'rm aa'
  $ hg up -q default
  $ echo aa >> aa
  $ hg ci -m aa
  $ hg merge -q bar --config ui.interactive=True << EOF
  > c
  > EOF
  local [working copy] changed aa which other [merge rev] deleted
  use (c)hanged version, (d)elete, or leave (u)nresolved? c
  $ hg ci -m 'merge bar (with conflicts)'
  $ hg log --config diff.git=1 -pr .
  changeset:   33:7afcba911942
  tag:         tip
  parent:      32:6075d69d215d
  parent:      31:67db8847a540
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     merge bar (with conflicts)
  
  
  $ hg rm aa
  $ hg ci --amend -m 'merge bar (with conflicts, amended)'
  $ hg log --config diff.git=1 -pr .
  changeset:   35:376965e47ddd
  tag:         tip
  parent:      32:6075d69d215d
  parent:      31:67db8847a540
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     merge bar (with conflicts, amended)
  
  diff --git a/aa b/aa
  deleted file mode 100644
  --- a/aa
  +++ /dev/null
  @@ -1,4 +0,0 @@
  -a
  -a
  -aa
  -aa
  
Issue 3445: amending with --close-branch a commit that created a new head should fail
This shouldn't be possible:

  $ hg up -q default
  $ hg branch closewithamend
  marked working directory as branch closewithamend
  $ echo foo > foo
  $ hg add foo
  $ hg ci -m..
  $ hg ci --amend --close-branch -m 'closing'
  abort: can only close branch heads
  [255]

This silliness fails:

  $ hg branch silliness
  marked working directory as branch silliness
  $ echo b >> b
  $ hg ci --close-branch -m'open and close'
  abort: can only close branch heads
  [255]

Test that amend with --secret creates new secret changeset forcibly
---------------------------------------------------------------------

  $ hg phase '.^::.'
  35: draft
  36: draft
  $ hg commit --amend --secret -m 'amend as secret' -q
  $ hg phase '.^::.'
  35: draft
  38: secret

Test that amend with --edit invokes editor forcibly
---------------------------------------------------

  $ hg parents --template "{desc}\n"
  amend as secret
  $ HGEDITOR=cat hg commit --amend -m "editor should be suppressed"
  $ hg parents --template "{desc}\n"
  editor should be suppressed

  $ hg status --rev '.^1::.'
  A foo
  $ HGEDITOR=cat hg commit --amend -m "editor should be invoked" --edit
  editor should be invoked
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to abort commit.
  HG: --
  HG: user: test
  HG: branch 'silliness'
  HG: added foo
  $ hg parents --template "{desc}\n"
  editor should be invoked

Test that "diff()" in committemplate works correctly for amending
-----------------------------------------------------------------

  $ cat >> .hg/hgrc <<EOF
  > [committemplate]
  > changeset.commit.amend = {desc}\n
  >     HG: M: {file_mods}
  >     HG: A: {file_adds}
  >     HG: R: {file_dels}
  >     {splitlines(diff()) % 'HG: {line}\n'}
  > EOF

  $ hg parents --template "M: {file_mods}\nA: {file_adds}\nR: {file_dels}\n"
  M: 
  A: foo
  R: 
  $ hg status -amr
  $ HGEDITOR=cat hg commit --amend -e -m "expecting diff of foo"
  expecting diff of foo
  
  HG: M: 
  HG: A: foo
  HG: R: 
  HG: diff -r 376965e47ddd foo
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +foo

  $ echo y > y
  $ hg add y
  $ HGEDITOR=cat hg commit --amend -e -m "expecting diff of foo and y"
  expecting diff of foo and y
  
  HG: M: 
  HG: A: foo y
  HG: R: 
  HG: diff -r 376965e47ddd foo
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +foo
  HG: diff -r 376965e47ddd y
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/y	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +y

  $ hg rm a
  $ HGEDITOR=cat hg commit --amend -e -m "expecting diff of a, foo and y"
  expecting diff of a, foo and y
  
  HG: M: 
  HG: A: foo y
  HG: R: a
  HG: diff -r 376965e47ddd a
  HG: --- a/a	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -1,2 +0,0 @@
  HG: -a
  HG: -a
  HG: diff -r 376965e47ddd foo
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +foo
  HG: diff -r 376965e47ddd y
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/y	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +y

  $ hg rm x
  $ HGEDITOR=cat hg commit --amend -e -m "expecting diff of a, foo, x and y"
  expecting diff of a, foo, x and y
  
  HG: M: 
  HG: A: foo y
  HG: R: a x
  HG: diff -r 376965e47ddd a
  HG: --- a/a	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -1,2 +0,0 @@
  HG: -a
  HG: -a
  HG: diff -r 376965e47ddd foo
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +foo
  HG: diff -r 376965e47ddd x
  HG: --- a/x	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -1,1 +0,0 @@
  HG: -x
  HG: diff -r 376965e47ddd y
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/y	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +y

  $ echo cccc >> cc
  $ hg status -amr
  M cc
  $ HGEDITOR=cat hg commit --amend -e -m "cc should be excluded" -X cc
  cc should be excluded
  
  HG: M: 
  HG: A: foo y
  HG: R: a x
  HG: diff -r 376965e47ddd a
  HG: --- a/a	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -1,2 +0,0 @@
  HG: -a
  HG: -a
  HG: diff -r 376965e47ddd foo
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +foo
  HG: diff -r 376965e47ddd x
  HG: --- a/x	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -1,1 +0,0 @@
  HG: -x
  HG: diff -r 376965e47ddd y
  HG: --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  HG: +++ b/y	Thu Jan 01 00:00:00 1970 +0000
  HG: @@ -0,0 +1,1 @@
  HG: +y

Check for issue4405
-------------------

Setup the repo with a file that gets moved in a second commit.
  $ hg init repo
  $ cd repo
  $ touch a0
  $ hg add a0
  $ hg commit -m a0
  $ hg mv a0 a1
  $ hg commit -m a1
  $ hg up -q 0
  $ hg log -G --template '{rev} {desc}'
  o  1 a1
  |
  @  0 a0
  

Now we branch the repro, but re-use the file contents, so we have a divergence
in the file revlog topology and the changelog topology.
  $ hg revert --rev 1 --all
  removing a0
  adding a1
  $ hg ci -qm 'a1-amend'
  $ hg log -G --template '{rev} {desc}'
  @  2 a1-amend
  |
  | o  1 a1
  |/
  o  0 a0
  

The way mercurial does amends is to create a temporary commit (rev 3) and then
fold the new and old commits together into another commit (rev 4). During this
process, _findlimit is called to check how far back to look for the transitive
closure of file copy information, but due to the divergence of the filelog
and changelog graph topologies, before _findlimit was fixed, it returned a rev
which was not far enough back in this case.
  $ hg mv a1 a2
  $ hg status --copies --rev 0
  A a2
    a0
  R a0
  $ hg ci --amend -q
  $ hg log -G --template '{rev} {desc}'
  @  4 a1-amend
  |
  | o  1 a1
  |/
  o  0 a0
  

Before the fix, the copy information was lost.
  $ hg status --copies --rev 0
  A a2
    a0
  R a0
  $ cd ..

Check that amend properly preserve rename from directory rename (issue-4516)

If a parent of the merge renames a full directory, any files added to the old
directory in the other parent will be renamed to the new directory. For some
reason, the rename metadata was when amending such merge. This test ensure we
do not regress. We have a dedicated repo because it needs a setup with renamed
directory)

  $ hg init issue4516
  $ cd issue4516
  $ mkdir olddirname
  $ echo line1 > olddirname/commonfile.py
  $ hg add olddirname/commonfile.py
  $ hg ci -m first

  $ hg branch newdirname
  marked working directory as branch newdirname
  (branches are permanent and global, did you want a bookmark?)
  $ hg mv olddirname newdirname
  moving olddirname/commonfile.py to newdirname/commonfile.py (glob)
  $ hg ci -m rename

  $ hg update default
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo line1 > olddirname/newfile.py
  $ hg add olddirname/newfile.py
  $ hg ci -m log

  $ hg up newdirname
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ # create newdirname/newfile.py
  $ hg merge default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m add
  $ 
  $ hg debugrename newdirname/newfile.py
  newdirname/newfile.py renamed from olddirname/newfile.py:690b295714aed510803d3020da9c70fca8336def (glob)
  $ hg status -C --change .
  A newdirname/newfile.py
  $ hg status -C --rev 1
  A newdirname/newfile.py
  $ hg status -C --rev 2
  A newdirname/commonfile.py
    olddirname/commonfile.py
  A newdirname/newfile.py
    olddirname/newfile.py
  R olddirname/commonfile.py
  R olddirname/newfile.py
  $ hg debugindex newdirname/newfile.py
     rev    offset  length  delta linkrev nodeid       p1           p2
       0         0      88     -1       3 34a4d536c0c0 000000000000 000000000000

  $ echo a >> newdirname/commonfile.py
  $ hg ci --amend -m bug
  $ hg debugrename newdirname/newfile.py
  newdirname/newfile.py renamed from olddirname/newfile.py:690b295714aed510803d3020da9c70fca8336def (glob)
  $ hg debugindex newdirname/newfile.py
     rev    offset  length  delta linkrev nodeid       p1           p2
       0         0      88     -1       3 34a4d536c0c0 000000000000 000000000000

#if execbit

Test if amend preserves executable bit changes
  $ chmod +x newdirname/commonfile.py
  $ hg ci -m chmod
  $ hg ci --amend -m "chmod amended"
  $ hg ci --amend -m "chmod amended second time"
  $ hg log -p --git -r .
  changeset:   8:b1326f52dddf
  branch:      newdirname
  tag:         tip
  parent:      5:7fd235f7cb2f
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     chmod amended second time
  
  diff --git a/newdirname/commonfile.py b/newdirname/commonfile.py
  old mode 100644
  new mode 100755
  
#endif