tests/test-rebase-obsolete2.t
author Arun Kulshreshtha <akulshreshtha@janestreet.com>
Tue, 30 Aug 2022 15:29:55 -0400
changeset 49491 c6a1beba27e9
parent 48687 f8f2ecdde4b5
permissions -rw-r--r--
bisect: avoid copying ancestor list for non-merge commits During a bisection, hg needs to compute a list of all ancestors for every candidate commit. This is accomplished via a bottom-up traversal of the set of candidates, during which each revision's ancestor list is populated using the ancestor list of its parent(s). Previously, this involved copying the entire list, which could be very long in if the bisection range was large. To help improve this, we can observe that each candidate commit is visited exactly once, at which point its ancestor list is copied into its children's lists and then dropped. In the case of non-merge commits, a commit's ancestor list consists exactly of its parent's list plus itself. This means that we can trivially reuse the parent's existing list for one of its non-merge children, which avoids copying entirely if that commit is the parent's only child. This makes bisections over linear ranges of commits much faster. During some informal testing in the large publicly-available `mozilla-central` repository, this noticeably sped up bisections over large ranges of history: Setup: $ cd mozilla-central $ hg bisect --reset $ hg bisect --good 0 $ hg log -r tip -T '{rev}\n' 628417 Test: $ time hg bisect --bad tip --noupdate Before: real 3m35.927s user 3m35.553s sys 0m0.319s After: real 1m41.142s user 1m40.810s sys 0m0.285s

==========================
Test rebase with obsolete
==========================

Enable obsolete

  $ cat >> $HGRCPATH << EOF
  > [command-templates]
  > log= {rev}:{node|short} {desc|firstline}{if(obsolete,' ({obsfate})')}
  > [experimental]
  > evolution.createmarkers=True
  > evolution.allowunstable=True
  > [phases]
  > publish=False
  > [extensions]
  > rebase=
  > drawdag=$TESTDIR/drawdag.py
  > strip=
  > EOF

Skip obsolete changeset even with multiple hops
-----------------------------------------------

setup

  $ hg init obsskip
  $ cd obsskip
  $ cat << EOF >> .hg/hgrc
  > [experimental]
  > rebaseskipobsolete = True
  > [extensions]
  > strip =
  > EOF
  $ echo A > A
  $ hg add A
  $ hg commit -m A
  $ echo B > B
  $ hg add B
  $ hg commit -m B0
  $ hg commit --amend -m B1
  $ hg commit --amend -m B2
  $ hg up --hidden 'desc(B0)'
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updated to hidden changeset a8b11f55fb19
  (hidden revision 'a8b11f55fb19' was rewritten as: 261e70097290)
  $ echo C > C
  $ hg add C
  $ hg commit -m C
  1 new orphan changesets
  created new head
  $ hg log -G
  @  4:212cb178bcbb C
  |
  | o  3:261e70097290 B2
  | |
  x |  1:a8b11f55fb19 B0 (rewritten using amend as 3:261e70097290)
  |/
  o  0:4a2df7238c3b A
  

Rebase finds its way in a chain of marker

  $ hg rebase -d 'desc(B2)'
  note: not rebasing 1:a8b11f55fb19 "B0", already in destination as 3:261e70097290 "B2"
  rebasing 4:212cb178bcbb tip "C"

Even when the chain include missing node

  $ hg up --hidden 'desc(B0)'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  updated to hidden changeset a8b11f55fb19
  (hidden revision 'a8b11f55fb19' was rewritten as: 261e70097290)
  $ echo D > D
  $ hg add D
  $ hg commit -m D
  1 new orphan changesets
  created new head
  $ hg --hidden strip -r 'desc(B1)'
  saved backup bundle to $TESTTMP/obsskip/.hg/strip-backup/86f6414ccda7-b1c452ee-backup.hg
  1 new orphan changesets
  $ hg log -G
  @  5:1a79b7535141 D
  |
  | o  4:ff2c4d47b71d C
  | |
  | o  2:261e70097290 B2
  | |
  x |  1:a8b11f55fb19 B0 (rewritten using amend as 2:261e70097290)
  |/
  o  0:4a2df7238c3b A
  

  $ hg rebase -d 'desc(B2)'
  note: not rebasing 1:a8b11f55fb19 "B0", already in destination as 2:261e70097290 "B2"
  rebasing 5:1a79b7535141 tip "D"
  $ hg up 4
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo "O" > O
  $ hg add O
  $ hg commit -m O
  $ echo "P" > P
  $ hg add P
  $ hg commit -m P
  $ hg log -G
  @  8:8d47583e023f P
  |
  o  7:360bbaa7d3ce O
  |
  | o  6:9c48361117de D
  | |
  o |  4:ff2c4d47b71d C
  |/
  o  2:261e70097290 B2
  |
  o  0:4a2df7238c3b A
  
  $ hg debugobsolete `hg log -r 7 -T '{node}\n'` --config experimental.evolution=true
  1 new obsolescence markers
  obsoleted 1 changesets
  1 new orphan changesets
  $ hg rebase -d 6 -r "4::"
  rebasing 4:ff2c4d47b71d "C"
  note: not rebasing 7:360bbaa7d3ce "O", it has no successor
  rebasing 8:8d47583e023f tip "P"

If all the changeset to be rebased are obsolete and present in the destination, we
should display a friendly error message

  $ hg log -G
  @  10:121d9e3bc4c6 P
  |
  o  9:4be60e099a77 C
  |
  o  6:9c48361117de D
  |
  o  2:261e70097290 B2
  |
  o  0:4a2df7238c3b A
  

  $ hg up 9
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo "non-relevant change" > nonrelevant
  $ hg add nonrelevant
  $ hg commit -m nonrelevant
  created new head
  $ hg debugobsolete `hg log -r 11 -T '{node}\n'` --config experimental.evolution=true
  1 new obsolescence markers
  obsoleted 1 changesets
  $ hg log -G
  @  11:f44da1f4954c nonrelevant (pruned)
  |
  | o  10:121d9e3bc4c6 P
  |/
  o  9:4be60e099a77 C
  |
  o  6:9c48361117de D
  |
  o  2:261e70097290 B2
  |
  o  0:4a2df7238c3b A
  
  $ hg rebase -r . -d 10
  note: not rebasing 11:f44da1f4954c tip "nonrelevant", it has no successor

If a rebase is going to create divergence, it should abort

  $ hg log -G
  @  10:121d9e3bc4c6 P
  |
  o  9:4be60e099a77 C
  |
  o  6:9c48361117de D
  |
  o  2:261e70097290 B2
  |
  o  0:4a2df7238c3b A
  

  $ hg up 9
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo "john" > doe
  $ hg add doe
  $ hg commit -m "john doe"
  created new head
  $ hg up 10
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo "foo" > bar
  $ hg add bar
  $ hg commit --amend -m "10'"
  $ hg up 10 --hidden
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  updated to hidden changeset 121d9e3bc4c6
  (hidden revision '121d9e3bc4c6' was rewritten as: 77d874d096a2)
  $ echo "bar" > foo
  $ hg add foo
  $ hg commit -m "bar foo"
  1 new orphan changesets
  created new head
  $ hg log -G
  @  14:73568ab6879d bar foo
  |
  | o  13:77d874d096a2 10'
  | |
  | | o  12:3eb461388009 john doe
  | |/
  x |  10:121d9e3bc4c6 P (rewritten using amend as 13:77d874d096a2)
  |/
  o  9:4be60e099a77 C
  |
  o  6:9c48361117de D
  |
  o  2:261e70097290 B2
  |
  o  0:4a2df7238c3b A
  
  $ hg summary
  parent: 14:73568ab6879d tip (orphan)
   bar foo
  branch: default
  commit: (clean)
  update: 2 new changesets, 3 branch heads (merge)
  phases: 8 draft
  orphan: 1 changesets
  $ hg rebase -s 10 -d 12
  abort: this rebase will cause divergences from: 121d9e3bc4c6
  (to force the rebase please set experimental.evolution.allowdivergence=True)
  [20]
  $ hg log -G
  @  14:73568ab6879d bar foo
  |
  | o  13:77d874d096a2 10'
  | |
  | | o  12:3eb461388009 john doe
  | |/
  x |  10:121d9e3bc4c6 P (rewritten using amend as 13:77d874d096a2)
  |/
  o  9:4be60e099a77 C
  |
  o  6:9c48361117de D
  |
  o  2:261e70097290 B2
  |
  o  0:4a2df7238c3b A
  
With experimental.evolution.allowdivergence=True, rebase can create divergence

  $ hg rebase -s 10 -d 12 --config experimental.evolution.allowdivergence=True
  rebasing 10:121d9e3bc4c6 "P"
  rebasing 14:73568ab6879d tip "bar foo"
  2 new content-divergent changesets
  $ hg summary
  parent: 16:61bd55f69bc4 tip
   bar foo
  branch: default
  commit: (clean)
  update: 1 new changesets, 2 branch heads (merge)
  phases: 8 draft
  content-divergent: 2 changesets

rebase --continue + skipped rev because their successors are in destination
we make a change in trunk and work on conflicting changes to make rebase abort.

  $ hg log -G -r 16::
  @  16:61bd55f69bc4 bar foo
  |
  ~

Create the two changes in trunk
  $ printf "a" > willconflict
  $ hg add willconflict
  $ hg commit -m "willconflict first version"

  $ printf "dummy" > C
  $ hg commit -m "dummy change successor"

Create the changes that we will rebase
  $ hg update -C 16 -q
  $ printf "b" > willconflict
  $ hg add willconflict
  $ hg commit -m "willconflict second version"
  created new head
  $ printf "dummy" > K
  $ hg add K
  $ hg commit -m "dummy change"
  $ printf "dummy" > L
  $ hg add L
  $ hg commit -m "dummy change"
  $ hg debugobsolete `hg log -r ".^" -T '{node}'` `hg log -r 18 -T '{node}'` --config experimental.evolution=true
  1 new obsolescence markers
  obsoleted 1 changesets
  1 new orphan changesets

  $ hg log -G -r 16::
  @  21:7bdc8a87673d dummy change
  |
  x  20:8b31da3c4919 dummy change (rewritten as 18:601db7a18f51)
  |
  o  19:b82fb57ea638 willconflict second version
  |
  | o  18:601db7a18f51 dummy change successor
  | |
  | o  17:357ddf1602d5 willconflict first version
  |/
  o  16:61bd55f69bc4 bar foo
  |
  ~
  $ hg rebase -r ".^^ + .^ + ." -d 18
  rebasing 19:b82fb57ea638 "willconflict second version"
  merging willconflict
  warning: conflicts while merging willconflict! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
  [240]

  $ hg resolve --mark willconflict
  (no more unresolved files)
  continue: hg rebase --continue
  $ hg rebase --continue
  rebasing 19:b82fb57ea638 "willconflict second version"
  note: not rebasing 20:8b31da3c4919 "dummy change", already in destination as 18:601db7a18f51 "dummy change successor"
  rebasing 21:7bdc8a87673d tip "dummy change"
  $ cd ..

Can rebase pruned and rewritten commits with --keep

  $ hg init keep
  $ cd keep
  $ hg debugdrawdag <<'EOS'
  >   D
  >   |
  >   C
  >   |
  > F B E  # prune: B
  >  \|/   # rebase: C -> E
  >   A
  > EOS
  1 new orphan changesets

  $ hg rebase -b D -d F --keep
  rebasing 1:112478962961 B "B"
  rebasing 4:26805aba1e60 C "C"
  rebasing 5:f585351a92f8 D tip "D"

  $ cd ..