view tests/test-rebase-pull.t @ 42743:8c9a6adec67a

rust-discovery: using the children cache in add_missing

The DAG range computation often needs to get back to very old
revisions, and turns out to be disproportionately long, given
that the end goal is to remove the descendents of the given
missing revisons from the undecided set.

The fast iteration capabilities available in the Rust case make
it possible to avoid the DAG range entirely, at the cost of
precomputing the children cache, and to simply iterate on
children of the given missing revisions.

This is a case where staying on the same side of the interface
between the two languages has clear benefits.

On discoveries with initial undecided sets
small enough to bypass sampling entirely, the total cost of
computing the children cache and the subsequent iteration
becomes better than the Python + C counterpart, which relies on
reachableroots2.

For example, on a repo with more than one million revisions with
an initial undecided set of 11 elements, we get these figures:

Rust version with simple iteration
  addcommons: 57.287us
  first undecided computation: 184.278334ms
  first children cache computation: 131.056us
  addmissings iteration: 42.766us
  first addinfo total: 185.24 ms

Python + C version
  first addcommons: 0.29 ms
  addcommons 0.21 ms
  first undecided computation 191.35 ms
  addmissings 45.75 ms
  first addinfo total: 237.77 ms

On discoveries with large undecided sets, the initial price paid
makes the first addinfo slower than the Python + C version,
but that's more than compensated by the gain in sampling and
subsequent iterations.
Here's an extreme example with an undecided set of a million revisions:

Rust version:
  first undecided computation: 293.842629ms
  first children cache computation: 407.911297ms
  addmissings iteration: 34.312869ms
  first addinfo total: 776.02 ms
  taking initial sample
  query 2: sampling time: 1318.38 ms
  query 2; still undecided: 1005013, sample size is: 200
  addmissings: 143.062us

Python + C version:
  first undecided computation 298.13 ms
  addmissings 80.13 ms
  first addinfo total: 399.62 ms
  taking initial sample
  query 2: sampling time: 3957.23 ms
  query 2; still undecided: 1005013, sample size is: 200
  addmissings 52.88 ms

Differential Revision: https://phab.mercurial-scm.org/D6428

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > rebase=
  > histedit=
  > 
  > [alias]
  > tglog = log -G --template "{rev}: {node|short} '{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
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  new changesets 77ae9631bcca
  rebasing 2:ff8d69a621f9 "L1"
  saved backup bundle to $TESTTMP/b/.hg/strip-backup/ff8d69a621f9-160fa373-rebase.hg

  $ hg tglog
  @  3: d80cc2da061e 'L1'
  |
  o  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd 'C1'
  
Re-run:

  $ hg pull --rebase
  pulling from $TESTTMP/a
  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: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd '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
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 77ae9631bcca
  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: 77ae9631bcca 'R1'
  |
  ~

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

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

  $ hg tglog -l 1
  o  2: 77ae9631bcca 'R1'
  |
  ~

  $ cd ..

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

  $ cd a
  $ hg tglog
  @  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd '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: 77ae9631bcca 'R1'
  |
  @  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd 'C1'
  
  $ echo L1 > L1
  $ hg ci -Am L1
  adding L1
  created new head
  $ hg pull --rev tip --rebase
  pulling from $TESTTMP/a
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets 31cd3a05214e:770a61882ace
  rebasing 3:ff8d69a621f9 "L1"
  saved backup bundle to $TESTTMP/c/.hg/strip-backup/ff8d69a621f9-160fa373-rebase.hg
  $ hg tglog
  @  5: 518d153c0ba3 'L1'
  |
  o  4: 770a61882ace 'R3'
  |
  o  3: 31cd3a05214e 'R2'
  |
  o  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd 'C1'
  
pull --rebase works with bundle2 turned on

  $ cd ../a
  $ echo R4 > R4
  $ hg ci -Am R4
  adding R4
  $ hg tglog
  @  5: 00e3b7781125 'R4'
  |
  o  4: 770a61882ace 'R3'
  |
  o  3: 31cd3a05214e 'R2'
  |
  o  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd 'C1'
  
  $ cd ../c
  $ hg pull --rebase
  pulling from $TESTTMP/a
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  new changesets 00e3b7781125
  rebasing 5:518d153c0ba3 "L1"
  saved backup bundle to $TESTTMP/c/.hg/strip-backup/518d153c0ba3-73407f14-rebase.hg
  $ hg tglog
  @  6: 0d0727eb7ce0 'L1'
  |
  o  5: 00e3b7781125 'R4'
  |
  o  4: 770a61882ace 'R3'
  |
  o  3: 31cd3a05214e 'R2'
  |
  o  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd '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: 88dd24261747 'R5'
  |
  o  5: 00e3b7781125 'R4'
  |
  o  4: 770a61882ace 'R3'
  |
  o  3: 31cd3a05214e 'R2'
  |
  o  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd '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
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  new changesets 88dd24261747
  rebasing 6:0d0727eb7ce0 "L1"
  rebasing 7:c1f58876e3bf "L2"
  saved backup bundle to $TESTTMP/c/.hg/strip-backup/0d0727eb7ce0-ef61ccb2-rebase.hg
  $ hg tglog
  o  8: 6dc0ea5dcf55 'L2'
  |
  @  7: 864e0a2d2614 'L1'
  |
  o  6: 88dd24261747 'R5'
  |
  o  5: 00e3b7781125 'R4'
  |
  o  4: 770a61882ace 'R3'
  |
  o  3: 31cd3a05214e 'R2'
  |
  o  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd '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
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  new changesets 65bc164c1d9b
  nothing to rebase - updating instead
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updated to "65bc164c1d9b: R6"
  1 other heads for branch "default"
  $ hg tglog
  @  9: 65bc164c1d9b 'R6'
  |
  | o  8: 6dc0ea5dcf55 'L2'
  | |
  | o  7: 864e0a2d2614 'L1'
  |/
  o  6: 88dd24261747 'R5'
  |
  o  5: 00e3b7781125 'R4'
  |
  o  4: 770a61882ace 'R3'
  |
  o  3: 31cd3a05214e 'R2'
  |
  o  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd '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
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 39c381359968
  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
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  new changesets f7d3e42052f9
  rebasing 7:864e0a2d2614 "L1"
  rebasing 8:6dc0ea5dcf55 "L2"
  saved backup bundle to $TESTTMP/c/.hg/strip-backup/864e0a2d2614-2f72c89c-rebase.hg
  $ hg tglog
  @  12: 3603a865eea0 'L2'
  |
  o  11: bcc8a9cd04bf 'L1'
  |
  o  10: f7d3e42052f9 'R7'
  |
  | o  9: 41fab4eef82f 'M1'
  |/
  | o  8: 39c381359968 'B1' unrelatedbranch
  |/
  o  7: 65bc164c1d9b 'R6'
  |
  o  6: 88dd24261747 'R5'
  |
  o  5: 00e3b7781125 'R4'
  |
  o  4: 770a61882ace 'R3'
  |
  o  3: 31cd3a05214e 'R2'
  |
  o  2: 77ae9631bcca 'R1'
  |
  o  1: 783333faa078 'C2'
  |
  o  0: 05d58a0c15dd 'C1'