view tests/test-rebase-pull.t @ 32200:4d504e541d3d

rebase: use matcher to optimize manifestmerge

The old merge code would call manifestmerge and calculate the complete diff
between the source to the destination. In many cases, like rebase, the vast
majority of differences between the source and destination are irrelevant
because they are differences between the destination and the common ancestor
only, and therefore don't affect the merge. Since most actions are 'keep', all
the effort to compute them is wasted.

Instead, let's compute the difference between the source and the common ancestor
and only perform the diff of those files against the merge destination. When
using treemanifest, this lets us avoid loading almost the entire tree when
rebasing from a very old ancestor. This speeds up rebase of an old stack of 27
commits by 20x.

In mozilla-central, without treemanifest, when rebasing a commit from
default~100000 to default, this speeds up the manifestmerge step from 2.6s to
1.2s.  However, the additional diff adds an overhead to all manifestmerge calls,
especially for flat manifests. When rebasing a commit from default~1 to default
it appears to add 100ms in mozilla-central. While we could put this optimization
behind a flag, I think the fact that it makes merge O(number of changes being
applied) instead of O(number of changes between X and Y) justifies it.

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


  $ hg init a
  $ cd a

  $ echo C1 > C1
  $ hg ci -Am C1
  adding C1

  $ echo C2 > C2
  $ hg ci -Am C2
  adding C2

  $ cd ..

  $ hg clone a b
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg clone a c
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd b

  $ echo L1 > L1
  $ hg ci -Am L1
  adding L1


  $ cd ../a

  $ echo R1 > R1
  $ hg ci -Am R1
  adding R1


  $ cd ../b

Now b has one revision to be pulled from a:

  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  rebasing 2:ff8d69a621f9 "L1"
  saved backup bundle to $TESTTMP/b/.hg/strip-backup/ff8d69a621f9-160fa373-backup.hg (glob)

  $ hg tglog
  @  3: 'L1'
  |
  o  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'
  
Re-run:

  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  no changes found

Abort pull early if working dir is not clean:

  $ echo L1-mod > L1
  $ hg pull --rebase
  abort: uncommitted changes
  (cannot pull with rebase: please commit or shelve your changes first)
  [255]
  $ hg update --clean --quiet

Abort pull early if another operation (histedit) is in progress:

  $ hg histedit . -q --commands - << EOF
  > edit d80cc2da061e histedit: generate unfinished state
  > EOF
  Editing (d80cc2da061e), you may commit or record as needed now.
  (hg histedit --continue to resume)
  [1]
  $ hg pull --rebase
  abort: histedit in progress
  (use 'hg histedit --continue' or 'hg histedit --abort')
  [255]
  $ hg histedit --abort --quiet

Abort pull early with pending uncommitted merge:

  $ cd ..
  $ hg clone --noupdate c d
  $ cd d
  $ hg tglog
  o  1: 'C2'
  |
  o  0: 'C1'
  
  $ hg update --quiet 0
  $ echo M1 > M1
  $ hg commit --quiet -Am M1
  $ hg update --quiet 1
  $ hg merge 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg pull --rebase
  abort: outstanding uncommitted merge
  (cannot pull with rebase: please commit or shelve your changes first)
  [255]
  $ hg update --clean --quiet

Abort pull early with unclean subrepo:
  $ echo s = s > .hgsub
  $ hg add .hgsub
  $ hg init s
  $ hg commit -m "generated a subrepo"
  $ echo a > s/a
  $ hg -R s add s/a
  $ hg pull --rebase
  abort: uncommitted changes in subrepository 's'
  (cannot pull with rebase: please commit or shelve your changes first)
  [255]

Invoke pull --rebase and nothing to rebase:

  $ cd ../c

  $ hg book norebase
  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  nothing to rebase - updating instead
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updating bookmark norebase

  $ hg tglog -l 1
  @  2: 'R1'
  |
  ~

pull --rebase --update should ignore --update:

  $ hg pull --rebase --update
  pulling from $TESTTMP/a (glob)
  searching for changes
  no changes found

pull --rebase doesn't update if nothing has been pulled:

  $ hg up -q 1

  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  no changes found

  $ hg tglog -l 1
  o  2: 'R1'
  |
  ~

  $ cd ..

pull --rebase works when a specific revision is pulled (issue3619)

  $ cd a
  $ hg tglog
  @  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'
  
  $ echo R2 > R2
  $ hg ci -Am R2
  adding R2
  $ echo R3 > R3
  $ hg ci -Am R3
  adding R3
  $ cd ../c
  $ hg tglog
  o  2: 'R1'
  |
  @  1: 'C2'
  |
  o  0: 'C1'
  
  $ echo L1 > L1
  $ hg ci -Am L1
  adding L1
  created new head
  $ hg pull --rev tip --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  rebasing 3:ff8d69a621f9 "L1"
  saved backup bundle to $TESTTMP/c/.hg/strip-backup/ff8d69a621f9-160fa373-backup.hg (glob)
  $ hg tglog
  @  5: 'L1'
  |
  o  4: 'R3'
  |
  o  3: 'R2'
  |
  o  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'
  
pull --rebase works with bundle2 turned on

  $ cd ../a
  $ echo R4 > R4
  $ hg ci -Am R4
  adding R4
  $ hg tglog
  @  5: 'R4'
  |
  o  4: 'R3'
  |
  o  3: 'R2'
  |
  o  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'
  
  $ cd ../c
  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  rebasing 5:518d153c0ba3 "L1"
  saved backup bundle to $TESTTMP/c/.hg/strip-backup/518d153c0ba3-73407f14-backup.hg (glob)
  $ hg tglog
  @  6: 'L1'
  |
  o  5: 'R4'
  |
  o  4: 'R3'
  |
  o  3: 'R2'
  |
  o  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'
  

pull --rebase only update if there is nothing to rebase

  $ cd ../a
  $ echo R5 > R5
  $ hg ci -Am R5
  adding R5
  $ hg tglog
  @  6: 'R5'
  |
  o  5: 'R4'
  |
  o  4: 'R3'
  |
  o  3: 'R2'
  |
  o  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'
  
  $ cd ../c
  $ echo L2 > L2
  $ hg ci -Am L2
  adding L2
  $ hg up 'desc(L1)'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  rebasing 6:0d0727eb7ce0 "L1"
  rebasing 7:c1f58876e3bf "L2"
  saved backup bundle to $TESTTMP/c/.hg/strip-backup/0d0727eb7ce0-ef61ccb2-backup.hg (glob)
  $ hg tglog
  o  8: 'L2'
  |
  @  7: 'L1'
  |
  o  6: 'R5'
  |
  o  5: 'R4'
  |
  o  4: 'R3'
  |
  o  3: 'R2'
  |
  o  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'
  

pull --rebase update (no rebase) use proper update:

- warn about other head.

  $ cd ../a
  $ echo R6 > R6
  $ hg ci -Am R6
  adding R6
  $ cd ../c
  $ hg up 'desc(R5)'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  nothing to rebase - updating instead
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  1 other heads for branch "default"
  $ hg tglog
  @  9: 'R6'
  |
  | o  8: 'L2'
  | |
  | o  7: 'L1'
  |/
  o  6: 'R5'
  |
  o  5: 'R4'
  |
  o  4: 'R3'
  |
  o  3: 'R2'
  |
  o  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'
  

Multiple pre-existing heads on the branch
-----------------------------------------

Pull bring content, but nothing on the current branch, we should not consider
pre-existing heads.

  $ cd ../a
  $ hg branch unrelatedbranch
  marked working directory as branch unrelatedbranch
  (branches are permanent and global, did you want a bookmark?)
  $ echo B1 > B1
  $ hg commit -Am B1
  adding B1
  $ cd ../c
  $ hg up 'desc(L2)'
  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  nothing to rebase

There is two local heads and we pull a third one.
The second local head should not confuse the `hg pull rebase`.

  $ hg up 'desc(R6)'
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo M1 > M1
  $ hg commit -Am M1
  adding M1
  $ cd ../a
  $ hg up 'desc(R6)'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo R7 > R7
  $ hg commit -Am R7
  adding R7
  $ cd ../c
  $ hg up 'desc(L2)'
  2 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ hg pull --rebase
  pulling from $TESTTMP/a (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  rebasing 7:864e0a2d2614 "L1"
  rebasing 8:6dc0ea5dcf55 "L2"
  saved backup bundle to $TESTTMP/c/.hg/strip-backup/864e0a2d2614-2f72c89c-backup.hg (glob)
  $ hg tglog
  @  12: 'L2'
  |
  o  11: 'L1'
  |
  o  10: 'R7'
  |
  | o  9: 'M1'
  |/
  | o  8: 'B1' unrelatedbranch
  |/
  o  7: 'R6'
  |
  o  6: 'R5'
  |
  o  5: 'R4'
  |
  o  4: 'R3'
  |
  o  3: 'R2'
  |
  o  2: 'R1'
  |
  o  1: 'C2'
  |
  o  0: 'C1'