view tests/test-rebase-interruptions.t @ 28000:d4247c306d82

copies: optimize forward copy detection logic for rebases

Forward copy detection (i.e. detecting what files have been moved/copied in
commit X since ancestor Y) previously required diff'ing the manifests of both X
and Y. This was expensive since it required reading both entire manifests and
doing a set difference (they weren't already in a set because of the
lazymanifest work). This cost almost 1 second on very large repositories, and
happens N times for a rebase of N commits.

This patch optimizes it for the case of rebase. In a rebase, we are comparing a
commit against it's immediate parent, and therefore we can know what files
changed by looking at ctx.files().  This lets us drastically decrease the size
of the set comparison, and makes it O(# of changes) instead of O(size of
manifest). This makes it take 1ms instead of 1000ms.

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


  $ hg init a
  $ cd a

  $ echo A > A
  $ hg ci -Am A
  adding A

  $ echo B > B
  $ hg ci -Am B
  adding B

  $ echo C >> A
  $ hg ci -m C

  $ hg up -q -C 0

  $ echo D >> A
  $ hg ci -m D
  created new head

  $ echo E > E
  $ hg ci -Am E
  adding E

  $ cd ..


Changes during an interruption - continue:

  $ hg clone -q -u . a a1
  $ cd a1

  $ hg tglog
  @  4: 'E'
  |
  o  3: 'D'
  |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
Rebasing B onto E:

  $ hg rebase -s 1 -d 4
  rebasing 1:27547f69f254 "B"
  rebasing 2:965c486023db "C"
  merging A
  warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]

Force a commit on C during the interruption:

  $ hg up -q -C 2 --config 'extensions.rebase=!'

  $ echo 'Extra' > Extra
  $ hg add Extra
  $ hg ci -m 'Extra' --config 'extensions.rebase=!'

Force this commit onto secret phase

  $ hg phase --force --secret 6

  $ hg tglogp
  @  6:secret 'Extra'
  |
  | o  5:draft 'B'
  | |
  | o  4:draft 'E'
  | |
  | o  3:draft 'D'
  | |
  o |  2:draft 'C'
  | |
  o |  1:draft 'B'
  |/
  o  0:draft 'A'
  
Resume the rebasing:

  $ hg rebase --continue
  already rebased 1:27547f69f254 "B" as 45396c49d53b
  rebasing 2:965c486023db "C"
  merging A
  warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]

Solve the conflict and go on:

  $ echo 'conflict solved' > A
  $ rm A.orig
  $ hg resolve -m A
  (no more unresolved files)
  continue: hg rebase --continue

  $ hg rebase --continue
  already rebased 1:27547f69f254 "B" as 45396c49d53b
  rebasing 2:965c486023db "C"
  warning: new changesets detected on source branch, not stripping

  $ hg tglogp
  o  7:draft 'C'
  |
  | o  6:secret 'Extra'
  | |
  o |  5:draft 'B'
  | |
  @ |  4:draft 'E'
  | |
  o |  3:draft 'D'
  | |
  | o  2:draft 'C'
  | |
  | o  1:draft 'B'
  |/
  o  0:draft 'A'
  
  $ cd ..


Changes during an interruption - abort:

  $ hg clone -q -u . a a2
  $ cd a2

  $ hg tglog
  @  4: 'E'
  |
  o  3: 'D'
  |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
Rebasing B onto E:

  $ hg rebase -s 1 -d 4
  rebasing 1:27547f69f254 "B"
  rebasing 2:965c486023db "C"
  merging A
  warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]

Force a commit on B' during the interruption:

  $ hg up -q -C 5 --config 'extensions.rebase=!'

  $ echo 'Extra' > Extra
  $ hg add Extra
  $ hg ci -m 'Extra' --config 'extensions.rebase=!'

  $ hg tglog
  @  6: 'Extra'
  |
  o  5: 'B'
  |
  o  4: 'E'
  |
  o  3: 'D'
  |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
Abort the rebasing:

  $ hg rebase --abort
  warning: new changesets detected on target branch, can't strip
  rebase aborted

  $ hg tglog
  @  6: 'Extra'
  |
  o  5: 'B'
  |
  o  4: 'E'
  |
  o  3: 'D'
  |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..

Changes during an interruption - abort (again):

  $ hg clone -q -u . a a3
  $ cd a3

  $ hg tglogp
  @  4:draft 'E'
  |
  o  3:draft 'D'
  |
  | o  2:draft 'C'
  | |
  | o  1:draft 'B'
  |/
  o  0:draft 'A'
  
Rebasing B onto E:

  $ hg rebase -s 1 -d 4
  rebasing 1:27547f69f254 "B"
  rebasing 2:965c486023db "C"
  merging A
  warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]

Change phase on B and B'

  $ hg up -q -C 5 --config 'extensions.rebase=!'
  $ hg phase --public 1
  $ hg phase --public 5
  $ hg phase --secret -f 2

  $ hg tglogp
  @  5:public 'B'
  |
  o  4:public 'E'
  |
  o  3:public 'D'
  |
  | o  2:secret 'C'
  | |
  | o  1:public 'B'
  |/
  o  0:public 'A'
  
Abort the rebasing:

  $ hg rebase --abort
  warning: can't clean up public changesets 45396c49d53b
  rebase aborted

  $ hg tglogp
  @  5:public 'B'
  |
  o  4:public 'E'
  |
  o  3:public 'D'
  |
  | o  2:secret 'C'
  | |
  | o  1:public 'B'
  |/
  o  0:public 'A'
  
  $ cd ..