view tests/test-rebase-conflicts.t @ 49777:e1953a34c110

bundle: emit full snapshot as is, without doing a redelta

With the new `forced` delta-reused policy, it become important to be able to
send full snapshot where full snapshot are needed. Otherwise, the fallback delta
will simply be used on the client side… creating monstrous delta chain, since
revision that are meant as a reset of delta-chain chain becoming too complex are
simply adding a new full delta-tree on the leaf of another one.

In the `non-forced` cases, client process full snapshot from the bundle
differently from deltas, so client will still try to convert the full snapshot
into a delta if possible. So this will no lead to pathological storage
explosion.

I have considered making this configurable, but the impact seems limited enough
that it does not seems to be worth it. Especially with the current
sparse-revlog format that use "delta-tree" with multiple level snapshots, full
snapshot are much less frequent and not that different from other intermediate
snapshot that we are already sending over the wire anyway.

CPU wise, this will help the bundling side a little as it will not need to
reconstruct revisions and compute deltas. The unbundling side might save a tiny
amount of CPU as it won't need to reconstruct the delta-base to reconstruct the
revision full text. This only slightly visible in some of the benchmarks. And
have no real impact on most of them.

### data-env-vars.name      = pypy-2018-08-01-zstd-sparse-revlog
  # benchmark.name          = perf-bundle
  # benchmark.variants.revs = last-40000
before:          11.467186 seconds
just-emit-full:  11.190576 seconds   (-2.41%)
with-pull-force: 11.041091 seconds   (-3.72%)
  # benchmark.name          = perf-unbundle
  # benchmark.variants.revs = last-40000
before:     16.744862
just-emit-full:: 16.561036 seconds   (-1.10%)
with-pull-force: 16.389344 seconds   (-2.12%)
  # benchmark.name          = pull
  # benchmark.variants.revs = last-40000
before:     26.870569
just-emit-full:  26.391188 seconds   (-1.78%)
with-pull-force: 25.633184 seconds   (-4.60%)


Space wise (so network-wise) the impact is fairly small. When taking compression into
account.

Below are tests the size of `hg bundle --all` for a handful of benchmark repositories
(with bzip, zstd compression and without it)

This show a small increase in the bundle size, but nothing really significant
except maybe for mozilla-try (+12%) that nobody really pulls large chunk of anyway.
Mozilla-try is also the repository that benefit the most for not having to
recompute deltas client size.

### mercurial:
bzip-before:     26 406 342 bytes
bzip-after:      26 691 543 bytes  +1.08%

zstd-before:     27 918 645 bytes
zstd-after:      28 075 896 bytes  +0.56%

none-before:     98 675 601 bytes
none-after:     100 411 237 bytes  +1.76%


### pypy
bzip-before:    201 295 752 bytes
bzip-after:     209 780 282 bytes  +4.21%

zstd-before:    202 974 795 bytes
zstd-after:     205 165 780 bytes  +1.08%

none-before:    871 070 261 bytes
none-after:     993 595 057 bytes +14.07%


### netbeans
bzip-before:    601 314 330 bytes
bzip-after:     614 246 241 bytes  +2.15%

zstd-before:    604 745 136 bytes
zstd-after:     615 497 705 bytes  +1.78%

none-before:  3 338 238 571 bytes
none-after:   3 439 422 535 bytes  +3.03%


### mozilla-central
bzip-before:  1 493 006 921 bytes
bzip-after:   1 549 650 570 bytes  +3.79%

zstd-before:  1 481 910 102 bytes
zstd-after:   1 513 052 415 bytes  +2.10%

none-before:  6 535 929 910 bytes
none-after:   7 010 191 342 bytes  +7.26%


### mozilla-try
bzip-before:  6 583 425 999 bytes
bzip-after:   7 423 536 928 bytes +12.76%

zstd-before:  6 021 009 212 bytes
zstd-after:   6 674 922 420 bytes +10.86%

none-before: 22 954 739 558 bytes
none-after:  26 013 854 771 bytes +13.32%

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > rebase=
  > drawdag=$TESTDIR/drawdag.py
  > 
  > [phases]
  > publish=False
  > 
  > [alias]
  > tglog = log -G --template "{rev}:{phase} '{desc}' {branches} {bookmarks}\n"
  > EOF

  $ hg init a
  $ cd a
  $ echo c1 >common
  $ hg add common
  $ hg ci -m C1

  $ echo c2 >>common
  $ hg ci -m C2

  $ echo c3 >>common
  $ hg ci -m C3

  $ hg up -q -C 1

  $ echo l1 >>extra
  $ hg add extra
  $ hg ci -m L1
  created new head

  $ sed -e 's/c2/l2/' common > common.new
  $ mv common.new common
  $ hg ci -m L2

  $ echo l3 >> extra2
  $ hg add extra2
  $ hg ci -m L3
  $ hg bookmark mybook

  $ hg phase --force --secret 4

  $ hg tglog
  @  5:secret 'L3'  mybook
  |
  o  4:secret 'L2'
  |
  o  3:draft 'L1'
  |
  | o  2:draft 'C3'
  |/
  o  1:draft 'C2'
  |
  o  0:draft 'C1'
  
Try to call --continue:

  $ hg rebase --continue
  abort: no rebase in progress
  [20]

Conflicting rebase:

  $ hg rebase -s 3 -d 2
  rebasing 3:3163e20567cc "L1"
  rebasing 4:46f0b057b5c0 "L2"
  merging common
  warning: conflicts while merging common! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]

  $ hg status --config commands.status.verbose=1
  M common
  ? common.orig
  # The repository is in an unfinished *rebase* state.
  
  # Unresolved merge conflicts:
  # 
  #     common
  # 
  # To mark files as resolved:  hg resolve --mark FILE
  
  # To continue:    hg rebase --continue
  # To abort:       hg rebase --abort
  # To stop:        hg rebase --stop
  

Try to continue without solving the conflict:

  $ hg rebase --continue
  abort: unresolved merge conflicts (see 'hg help resolve')
  [20]

Conclude rebase:

  $ echo 'resolved merge' >common
  $ hg resolve -m common
  (no more unresolved files)
  continue: hg rebase --continue
  $ hg rebase --continue
  already rebased 3:3163e20567cc "L1" as 3e046f2ecedb
  rebasing 4:46f0b057b5c0 "L2"
  rebasing 5:8029388f38dc mybook "L3"
  saved backup bundle to $TESTTMP/a/.hg/strip-backup/3163e20567cc-5ca4656e-rebase.hg

  $ hg tglog
  @  5:secret 'L3'  mybook
  |
  o  4:secret 'L2'
  |
  o  3:draft 'L1'
  |
  o  2:draft 'C3'
  |
  o  1:draft 'C2'
  |
  o  0:draft 'C1'
  
Check correctness:

  $ hg cat -r 0 common
  c1

  $ hg cat -r 1 common
  c1
  c2

  $ hg cat -r 2 common
  c1
  c2
  c3

  $ hg cat -r 3 common
  c1
  c2
  c3

  $ hg cat -r 4 common
  resolved merge

  $ hg cat -r 5 common
  resolved merge

Bookmark stays active after --continue
  $ hg bookmarks
   * mybook                    5:d67b21408fc0

  $ cd ..

Check that the right ancestors is used while rebasing a merge (issue4041)

  $ hg init issue4041
  $ cd issue4041
  $ hg unbundle "$TESTDIR/bundles/issue4041.hg"
  adding changesets
  adding manifests
  adding file changes
  added 11 changesets with 8 changes to 3 files (+1 heads)
  new changesets 24797d4f68de:2f2496ddf49d (11 drafts)
  (run 'hg heads' to see heads)
  $ hg up default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg log -G
  o    changeset:   10:2f2496ddf49d
  |\   branch:      f1
  | |  tag:         tip
  | |  parent:      7:4c9fbe56a16f
  | |  parent:      9:e31216eec445
  | |  user:        szhang
  | |  date:        Thu Sep 05 12:59:39 2013 -0400
  | |  summary:     merge
  | |
  | o  changeset:   9:e31216eec445
  | |  branch:      f1
  | |  user:        szhang
  | |  date:        Thu Sep 05 12:59:10 2013 -0400
  | |  summary:     more changes to f1
  | |
  | o    changeset:   8:8e4e2c1a07ae
  | |\   branch:      f1
  | | |  parent:      2:4bc80088dc6b
  | | |  parent:      6:400110238667
  | | |  user:        szhang
  | | |  date:        Thu Sep 05 12:57:59 2013 -0400
  | | |  summary:     bad merge
  | | |
  o | |  changeset:   7:4c9fbe56a16f
  |/ /   branch:      f1
  | |    parent:      2:4bc80088dc6b
  | |    user:        szhang
  | |    date:        Thu Sep 05 12:54:00 2013 -0400
  | |    summary:     changed f1
  | |
  | o  changeset:   6:400110238667
  | |  branch:      f2
  | |  parent:      4:12e8ec6bb010
  | |  user:        szhang
  | |  date:        Tue Sep 03 13:58:02 2013 -0400
  | |  summary:     changed f2 on f2
  | |
  | | @  changeset:   5:d79e2059b5c0
  | | |  parent:      3:8a951942e016
  | | |  user:        szhang
  | | |  date:        Tue Sep 03 13:57:39 2013 -0400
  | | |  summary:     changed f2 on default
  | | |
  | o |  changeset:   4:12e8ec6bb010
  | |/   branch:      f2
  | |    user:        szhang
  | |    date:        Tue Sep 03 13:57:18 2013 -0400
  | |    summary:     created f2 branch
  | |
  | o  changeset:   3:8a951942e016
  | |  parent:      0:24797d4f68de
  | |  user:        szhang
  | |  date:        Tue Sep 03 13:57:11 2013 -0400
  | |  summary:     added f2.txt
  | |
  o |  changeset:   2:4bc80088dc6b
  | |  branch:      f1
  | |  user:        szhang
  | |  date:        Tue Sep 03 13:56:20 2013 -0400
  | |  summary:     added f1.txt
  | |
  o |  changeset:   1:ef53c9e6b608
  |/   branch:      f1
  |    user:        szhang
  |    date:        Tue Sep 03 13:55:26 2013 -0400
  |    summary:     created f1 branch
  |
  o  changeset:   0:24797d4f68de
     user:        szhang
     date:        Tue Sep 03 13:55:08 2013 -0400
     summary:     added default.txt
  
  $ hg rebase -s9 -d2 --debug # use debug to really check merge base used
  rebase onto 4bc80088dc6b starting from e31216eec445
  rebasing on disk
  rebase status stored
  rebasing 9:e31216eec445 "more changes to f1"
   future parents are 2 and -1
   update to 2:4bc80088dc6b
  resolving manifests
   branchmerge: False, force: True, partial: False
   ancestor: d79e2059b5c0+, local: d79e2059b5c0+, remote: 4bc80088dc6b
   f2.txt: other deleted -> r
  removing f2.txt
   f1.txt: remote created -> g
  getting f1.txt
   merge against 9:e31216eec445
     detach base 8:8e4e2c1a07ae
  resolving manifests
   branchmerge: True, force: True, partial: False
   ancestor: 8e4e2c1a07ae, local: 4bc80088dc6b+, remote: e31216eec445
   f1.txt: remote is newer -> g
  getting f1.txt
  committing files:
  f1.txt
  committing manifest
  committing changelog
  updating the branch cache
  rebased as 19c888675e13
  rebase status stored
  rebasing 10:2f2496ddf49d tip "merge"
   future parents are 11 and 7
   already in destination
   merge against 10:2f2496ddf49d
     detach base 9:e31216eec445
  resolving manifests
   branchmerge: True, force: True, partial: False
   ancestor: e31216eec445, local: 19c888675e13+, remote: 2f2496ddf49d
   f1.txt: remote is newer -> g
  getting f1.txt
  committing files:
  f1.txt
  committing manifest
  committing changelog
  updating the branch cache
  rebased as c1ffa3b5274e
  rebase status stored
  rebase merging completed
  update back to initial working directory parent
  resolving manifests
   branchmerge: False, force: False, partial: False
   ancestor: c1ffa3b5274e, local: c1ffa3b5274e+, remote: d79e2059b5c0
   f1.txt: other deleted -> r
  removing f1.txt
   f2.txt: remote created -> g
  getting f2.txt
  2 changesets found
  list of changesets:
  e31216eec445e44352c5f01588856059466a24c9
  2f2496ddf49d69b5ef23ad8cf9fb2e0e4faf0ac2
  bundle2-output-bundle: "HG20", (1 params) 3 parts total
  bundle2-output-part: "changegroup" (params: 1 mandatory 1 advisory) streamed payload
  bundle2-output-part: "cache:rev-branch-cache" (advisory) streamed payload
  bundle2-output-part: "phase-heads" 24 bytes payload
  saved backup bundle to $TESTTMP/issue4041/.hg/strip-backup/e31216eec445-15f7a814-rebase.hg
  3 changesets found
  list of changesets:
  4c9fbe56a16f30c0d5dcc40ec1a97bbe3325209c
  19c888675e133ab5dff84516926a65672eaf04d9
  c1ffa3b5274e92a9388fe782854e295d2e8d0443
  bundle2-output-bundle: "HG20", 3 parts total
  bundle2-output-part: "changegroup" (params: 1 mandatory 1 advisory) streamed payload
  bundle2-output-part: "cache:rev-branch-cache" (advisory) streamed payload
  bundle2-output-part: "phase-heads" 24 bytes payload
  adding branch
  bundle2-input-bundle: with-transaction
  bundle2-input-part: "changegroup" (params: 1 mandatory 1 advisory) supported
  adding changesets
  add changeset 4c9fbe56a16f
  add changeset 19c888675e13
  add changeset c1ffa3b5274e
  adding manifests
  adding file changes
  adding f1.txt revisions
  bundle2-input-part: total payload size 1739
  bundle2-input-part: "cache:rev-branch-cache" (advisory) supported
  bundle2-input-part: total payload size 74
  bundle2-input-part: "phase-heads" supported
  bundle2-input-part: total payload size 24
  bundle2-input-bundle: 3 parts total
  truncating cache/rbc-revs-v1 to 72
  added 2 changesets with 2 changes to 1 files
  updating the branch cache
  invalid branch cache (served): tip differs
  invalid branch cache (served.hidden): tip differs
  rebase completed

Test minimization of merge conflicts
  $ hg up -q null
  $ echo a > a
  $ hg add a
  $ hg commit -q -m 'a'
  $ echo b >> a
  $ hg commit -q -m 'ab'
  $ hg bookmark ab
  $ hg up -q '.^'
  $ echo b >> a
  $ echo c >> a
  $ hg commit -q -m 'abc'
  $ hg rebase -s 7bc217434fc1 -d ab --keep
  rebasing 13:7bc217434fc1 tip "abc"
  merging a
  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]
  $ hg diff
  diff -r 328e4ab1f7cc a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	* (glob)
  @@ -1,2 +1,6 @@
   a
   b
  +<<<<<<< dest:   328e4ab1f7cc ab - test: ab
  +=======
  +c
  +>>>>>>> source: 7bc217434fc1 - test: abc
  $ hg rebase --abort
  rebase aborted
  $ hg up -q -C 7bc217434fc1
  $ hg rebase -s . -d ab --keep -t internal:merge3
  rebasing 13:7bc217434fc1 tip "abc"
  merging a
  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]
  $ hg diff
  diff -r 328e4ab1f7cc a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	* (glob)
  @@ -1,2 +1,8 @@
   a
  +<<<<<<< dest:             328e4ab1f7cc ab - test: ab
   b
  +||||||| parent of source: cb9a9f314b8b - test: a
  +=======
  +b
  +c
  +>>>>>>> source:           7bc217434fc1 - test: abc

Test rebase with obsstore turned on and off (issue5606)

  $ cd $TESTTMP
  $ hg init b
  $ cd b
  $ hg debugdrawdag <<'EOS'
  > D
  > |
  > C
  > |
  > B E
  > |/
  > A
  > EOS

  $ hg update E -q
  $ echo 3 > B
  $ hg commit --amend -m E -A B -q
  $ hg rebase -r B+D -d . --config experimental.evolution=true
  rebasing 1:112478962961 B "B"
  merging B
  warning: conflicts while merging B! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]

  $ echo 4 > B
  $ hg resolve -m
  (no more unresolved files)
  continue: hg rebase --continue
  $ hg rebase --continue --config experimental.evolution=none
  rebasing 1:112478962961 B "B"
  rebasing 3:f585351a92f8 D "D"
  warning: orphaned descendants detected, not stripping 112478962961
  saved backup bundle to $TESTTMP/b/.hg/strip-backup/f585351a92f8-e536a9e4-rebase.hg

  $ rm .hg/localtags
  $ hg tglog
  o  5:draft 'D'
  |
  o  4:draft 'B'
  |
  @  3:draft 'E'
  |
  | o  2:draft 'C'
  | |
  | o  1:draft 'B'
  |/
  o  0:draft 'A'
  

Test where the conflict happens when rebasing a merge commit

  $ cd $TESTTMP
  $ hg init conflict-in-merge
  $ cd conflict-in-merge
  $ hg debugdrawdag <<'EOS'
  > F # F/conflict = foo\n
  > |\
  > D E
  > |/
  > C B # B/conflict = bar\n
  > |/
  > A
  > EOS

  $ hg co F
  5 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg rebase -d B
  rebasing 2:dc0947a82db8 C "C"
  rebasing 3:e7b3f00ed42e D "D"
  rebasing 4:03ca77807e91 E "E"
  rebasing 5:9a6b91dc2044 F tip "F"
  merging conflict
  warning: conflicts while merging conflict! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]
  $ hg tglog
  @  8:draft 'E'
  |
  | @  7:draft 'D'
  |/
  o  6:draft 'C'
  |
  | %    5:draft 'F'
  | |\
  | | o  4:draft 'E'
  | | |
  | o |  3:draft 'D'
  | |/
  | o  2:draft 'C'
  | |
  o |  1:draft 'B'
  |/
  o  0:draft 'A'
  
  $ echo baz > conflict
  $ hg resolve -m
  (no more unresolved files)
  continue: hg rebase --continue
  $ hg rebase -c
  already rebased 2:dc0947a82db8 C "C" as 0199610c343e
  already rebased 3:e7b3f00ed42e D "D" as f0dd538aaa63
  already rebased 4:03ca77807e91 E "E" as cbf25af8347d
  rebasing 5:9a6b91dc2044 F "F"
  saved backup bundle to $TESTTMP/conflict-in-merge/.hg/strip-backup/dc0947a82db8-ca7e7d5b-rebase.hg
  $ hg tglog
  @    5:draft 'F'
  |\
  | o  4:draft 'E'
  | |
  o |  3:draft 'D'
  |/
  o  2:draft 'C'
  |
  o  1:draft 'B'
  |
  o  0:draft 'A'