tests/test-rebase-collapse.t

nodemap: introduce an option to use mmap to read the nodemap mapping

The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.

This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).

Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:

Before:

 * do not use the persistent nodemap
 * use the CPython implementation of the index for nodemap
 * use mmapping of the changelog index

After:

 * use the MixedIndex Rust code, with the NodeTree object for nodemap access
   (still in review)
 * use the persistent nodemap data from disk
 * access the persistent nodemap data through mmap
 * use mmapping of the changelog index

The persistent nodemap greatly speed up  most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.

Here are some numbers (in seconds) for the reference copy of mozilla-try:

Revset            Before   After     abs-change speedup

-10000:           0.004622 0.005532   0.000910  ×   0.83
-10:              0.000050 0.000132   0.000082  ×   0.37
tip               0.000052 0.000085   0.000033  ×   0.61
0 + (-10000:)     0.028222 0.005337  -0.022885  ×   5.29
0                 0.023521 0.000084  -0.023437  × 280.01
(-10000:) + 0     0.235539 0.005308  -0.230231  ×  44.37
(-10:) + :9       0.232883 0.000180  -0.232703  ×1293.79
(-10000:) + (:99) 0.238735 0.005358  -0.233377  ×  44.55
:99 + (-10000:)   0.317942 0.005593  -0.312349  ×  56.84
:9 + (-10:)       0.313372 0.000179  -0.313193  ×1750.68
:9                0.316450 0.000143  -0.316307  ×2212.93


On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.

Here are some numbers (in seconds) for the reference copy of mercurial:

Revset            Before   After     abs-change speedup
-10:              0.000065 0.000097   0.000032  × 0.67
tip               0.000063 0.000078   0.000015  × 0.80
0                 0.000561 0.000079  -0.000482  × 7.10
-10000:           0.004609 0.003648  -0.000961  × 1.26
0 + (-10000:)     0.005023 0.003715  -0.001307  × 1.35
(-10:) + :9       0.002187 0.000108  -0.002079  ×20.25
(-10000:) + 0     0.006252 0.003716  -0.002536  × 1.68
(-10000:) + (:99) 0.006367 0.003707  -0.002660  × 1.71
:9 + (-10:)       0.003846 0.000110  -0.003736  ×34.96
:9                0.003854 0.000099  -0.003755  ×38.92
:99 + (-10000:)   0.007644 0.003778  -0.003866  × 2.02

Differential Revision: https://phab.mercurial-scm.org/D7894

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

Highest phase of source commits is used:

  $ hg init phase
  $ cd phase
  $ hg debugdrawdag << 'EOF'
  >   D
  >   |
  > F C
  > | |
  > E B
  > |/
  > A
  > EOF

  $ hg phase --force --secret D

  $ cat > $TESTTMP/editor.sh <<EOF
  > echo "==== before editing"
  > cat \$1
  > echo "===="
  > echo "edited manually" >> \$1
  > EOF
  $ HGEDITOR="sh $TESTTMP/editor.sh" hg rebase --collapse --keepbranches -e --source B --dest F
  rebasing 1:112478962961 "B" (B)
  rebasing 3:26805aba1e60 "C" (C)
  rebasing 5:f585351a92f8 "D" (D tip)
  ==== before editing
  Collapsed revision
  * B
  * C
  * D
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to abort commit.
  HG: --
  HG: user: test
  HG: branch 'default'
  HG: added B
  HG: added C
  HG: added D
  ====
  saved backup bundle to $TESTTMP/phase/.hg/strip-backup/112478962961-cb2a9b47-rebase.hg

  $ hg tglogp
  o  3: 92fa5f5fe108 secret 'Collapsed revision
  |  * B
  |  * C
  |  * D
  |
  |
  |  edited manually'
  o  2: 64a8289d2492 draft 'F'
  |
  o  1: 7fb047a69f22 draft 'E'
  |
  o  0: 426bada5c675 draft 'A'
  
  $ hg manifest --rev tip
  A
  B
  C
  D
  E
  F

  $ cd ..


Merge gets linearized:

  $ hg init linearized-merge
  $ cd linearized-merge

  $ hg debugdrawdag << 'EOF'
  > F D
  > |/|
  > C B
  > |/
  > A
  > EOF

  $ hg phase --force --secret D
  $ hg rebase --source B --collapse --dest F
  rebasing 1:112478962961 "B" (B)
  rebasing 3:4e4f9194f9f1 "D" (D)
  saved backup bundle to $TESTTMP/linearized-merge/.hg/strip-backup/112478962961-e389075b-rebase.hg

  $ hg tglog
  o  3: 5bdc08b7da2b 'Collapsed revision
  |  * B
  |  * D'
  o  2: afc707c82df0 'F'
  |
  o  1: dc0947a82db8 'C'
  |
  o  0: 426bada5c675 'A'
  
  $ hg manifest --rev tip
  A
  B
  C
  F

  $ cd ..

Custom message:

  $ hg init message
  $ cd message

  $ hg debugdrawdag << 'EOF'
  >   C
  >   |
  > D B
  > |/
  > A
  > EOF


  $ hg rebase --base B -m 'custom message'
  abort: message can only be specified with collapse
  [255]

  $ cat > $TESTTMP/checkeditform.sh <<EOF
  > env | grep HGEDITFORM
  > true
  > EOF
  $ HGEDITOR="sh $TESTTMP/checkeditform.sh" hg rebase --source B --collapse -m 'custom message' -e --dest D
  rebasing 1:112478962961 "B" (B)
  rebasing 3:26805aba1e60 "C" (C tip)
  HGEDITFORM=rebase.collapse
  saved backup bundle to $TESTTMP/message/.hg/strip-backup/112478962961-f4131707-rebase.hg

  $ hg tglog
  o  2: 2f197b9a08f3 'custom message'
  |
  o  1: b18e25de2cf5 'D'
  |
  o  0: 426bada5c675 'A'
  
  $ hg manifest --rev tip
  A
  B
  C
  D

  $ cd ..

Rebase and collapse - more than one external (fail):

  $ hg init multiple-external-parents
  $ cd multiple-external-parents

  $ hg debugdrawdag << 'EOF'
  >   G
  >   |\
  >   | F
  >   | |
  >   D E
  >   |\|
  > H C B
  >  \|/
  >   A
  > EOF

  $ hg rebase -s C --dest H --collapse
  abort: unable to collapse on top of 3, there is more than one external parent: 1, 6
  [255]

Rebase and collapse - E onto H:

  $ hg rebase -s E --dest I --collapse # root (E) is not a merge
  abort: unknown revision 'I'!
  [255]

  $ hg tglog
  o    7: 64e264db77f0 'G'
  |\
  | o  6: 11abe3fb10b8 'F'
  | |
  | o  5: 49cb92066bfd 'E'
  | |
  o |  4: 4e4f9194f9f1 'D'
  |\|
  | | o  3: 575c4b5ec114 'H'
  | | |
  o---+  2: dc0947a82db8 'C'
   / /
  o /  1: 112478962961 'B'
  |/
  o  0: 426bada5c675 'A'
  
  $ hg manifest --rev tip
  A
  B
  C
  E
  F

  $ cd ..




Test that branchheads cache is updated correctly when doing a strip in which
the parent of the ancestor node to be stripped does not become a head and also,
the parent of a node that is a child of the node stripped becomes a head (node
3). The code is now much simpler and we could just test a simpler scenario
We keep it the test this way in case new complexity is injected.

Create repo b:

  $ hg init branch-heads
  $ cd branch-heads

  $ hg debugdrawdag << 'EOF'
  >   G
  >   |\
  >   | F
  >   | |
  >   D E
  >   |\|
  > H C B
  >  \|/
  >   A
  > EOF

  $ hg heads --template="{rev}:{node} {branch}\n"
  7:64e264db77f061f16d9132b70c5a58e2461fb630 default
  3:575c4b5ec114d64b681d33f8792853568bfb2b2c default

  $ cat $TESTTMP/branch-heads/.hg/cache/branch2-served
  64e264db77f061f16d9132b70c5a58e2461fb630 7
  575c4b5ec114d64b681d33f8792853568bfb2b2c o default
  64e264db77f061f16d9132b70c5a58e2461fb630 o default

  $ hg strip 4
  saved backup bundle to $TESTTMP/branch-heads/.hg/strip-backup/4e4f9194f9f1-5ec4b5e6-backup.hg

  $ cat $TESTTMP/branch-heads/.hg/cache/branch2-served
  11abe3fb10b8689b560681094b17fe161871d043 5
  dc0947a82db884575bb76ea10ac97b08536bfa03 o default
  575c4b5ec114d64b681d33f8792853568bfb2b2c o default
  11abe3fb10b8689b560681094b17fe161871d043 o default

  $ hg heads --template="{rev}:{node} {branch}\n"
  5:11abe3fb10b8689b560681094b17fe161871d043 default
  3:575c4b5ec114d64b681d33f8792853568bfb2b2c default
  2:dc0947a82db884575bb76ea10ac97b08536bfa03 default

  $ cd ..



Preserves external parent

  $ hg init external-parent
  $ cd external-parent

  $ hg debugdrawdag << 'EOF'
  >   H
  >   |\
  >   | G
  >   | |
  >   | F # F/E = F\n
  >   | |
  >   D E # D/D = D\n
  >   |\|
  > I C B
  >  \|/
  >   A
  > EOF

  $ hg rebase -s F --dest I --collapse # root (F) is not a merge
  rebasing 6:c82b08f646f1 "F" (F)
  file 'E' was deleted in local [dest] but was modified in other [source].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]

  $ echo F > E
  $ hg resolve -m
  (no more unresolved files)
  continue: hg rebase --continue
  $ hg rebase -c
  rebasing 6:c82b08f646f1 "F" (F)
  rebasing 7:a6db7fa104e1 "G" (G)
  rebasing 8:e1d201b72d91 "H" (H tip)
  saved backup bundle to $TESTTMP/external-parent/.hg/strip-backup/c82b08f646f1-f2721fbf-rebase.hg

  $ hg tglog
  o    6: 681daa3e686d 'Collapsed revision
  |\   * F
  | |  * G
  | |  * H'
  | | o  5: 49cb92066bfd 'E'
  | | |
  | o |  4: 09143c0bf13e 'D'
  | |\|
  o | |  3: 08ebfeb61bac 'I'
  | | |
  | o |  2: dc0947a82db8 'C'
  |/ /
  | o  1: 112478962961 'B'
  |/
  o  0: 426bada5c675 'A'
  
  $ hg manifest --rev tip
  A
  C
  D
  E
  F
  G
  I

  $ hg up tip -q
  $ cat E
  F

  $ cd ..

Rebasing from multiple bases:

  $ hg init multiple-bases
  $ cd multiple-bases
  $ hg debugdrawdag << 'EOF'
  >   C B
  > D |/
  > |/
  > A
  > EOF
  $ hg rebase --collapse -r 'B+C' -d D
  rebasing 1:fc2b737bb2e5 "B" (B)
  rebasing 2:dc0947a82db8 "C" (C)
  saved backup bundle to $TESTTMP/multiple-bases/.hg/strip-backup/dc0947a82db8-b0c1a7ea-rebase.hg
  $ hg tglog
  o  2: 2127ae44d291 'Collapsed revision
  |  * B
  |  * C'
  o  1: b18e25de2cf5 'D'
  |
  o  0: 426bada5c675 'A'
  
  $ cd ..

With non-contiguous commits:

  $ hg init non-contiguous
  $ cd non-contiguous
  $ cat >> .hg/hgrc <<EOF
  > [experimental]
  > evolution=all
  > EOF

  $ hg debugdrawdag << 'EOF'
  > F
  > |
  > E
  > |
  > D
  > |
  > C
  > |
  > B G
  > |/
  > A
  > EOF

BROKEN: should be allowed
  $ hg rebase --collapse -r 'B+D+F' -d G
  abort: unable to collapse on top of 2, there is more than one external parent: 3, 5
  [255]
  $ cd ..


  $ hg init multiple-external-parents-2
  $ cd multiple-external-parents-2
  $ hg debugdrawdag << 'EOF'
  > D       G
  > |\     /|
  > B C   E F
  >  \|   |/
  >   \ H /
  >    \|/
  >     A
  > EOF

  $ hg rebase --collapse -d H -s 'B+F'
  abort: unable to collapse on top of 5, there is more than one external parent: 1, 3
  [255]
  $ cd ..

With internal merge:

  $ hg init internal-merge
  $ cd internal-merge

  $ hg debugdrawdag << 'EOF'
  >   E
  >   |\
  >   C D
  >   |/
  > F B
  > |/
  > A
  > EOF


  $ hg rebase -s B --collapse --dest F
  rebasing 1:112478962961 "B" (B)
  rebasing 3:26805aba1e60 "C" (C)
  rebasing 4:be0ef73c17ad "D" (D)
  rebasing 5:02c4367d6973 "E" (E tip)
  saved backup bundle to $TESTTMP/internal-merge/.hg/strip-backup/112478962961-1dfb057b-rebase.hg

  $ hg tglog
  o  2: c0512a1797b0 'Collapsed revision
  |  * B
  |  * C
  |  * D
  |  * E'
  o  1: 8908a377a434 'F'
  |
  o  0: 426bada5c675 'A'
  
  $ hg manifest --rev tip
  A
  B
  C
  D
  F
  $ cd ..

Interactions between collapse and keepbranches
  $ hg init e
  $ cd e
  $ echo 'a' > a
  $ hg ci -Am 'A'
  adding a

  $ hg branch 'one'
  marked working directory as branch one
  (branches are permanent and global, did you want a bookmark?)
  $ echo 'b' > b
  $ hg ci -Am 'B'
  adding b

  $ hg branch 'two'
  marked working directory as branch two
  $ echo 'c' > c
  $ hg ci -Am 'C'
  adding c

  $ hg up -q 0
  $ echo 'd' > d
  $ hg ci -Am 'D'
  adding d

  $ hg tglog
  @  3: 41acb9dca9eb 'D'
  |
  | o  2: 8ac4a08debf1 'C' two
  | |
  | o  1: 1ba175478953 'B' one
  |/
  o  0: 1994f17a630e 'A'
  
  $ hg rebase --keepbranches --collapse -s 1 -d 3
  abort: cannot collapse multiple named branches
  [255]

  $ cd ..

Rebase, collapse and copies

  $ hg init copies
  $ cd copies
  $ hg unbundle "$TESTDIR/bundles/renames.hg"
  adding changesets
  adding manifests
  adding file changes
  added 4 changesets with 11 changes to 7 files (+1 heads)
  new changesets f447d5abf5ea:338e84e2e558 (4 drafts)
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg up -q tip
  $ hg tglog
  @  3: 338e84e2e558 'move2'
  |
  o  2: 6e7340ee38c0 'move1'
  |
  | o  1: 1352765a01d4 'change'
  |/
  o  0: f447d5abf5ea 'add'
  
  $ hg rebase --collapse -d 1
  rebasing 2:6e7340ee38c0 "move1"
  merging a and d to d
  merging b and e to e
  merging c and f to f
  rebasing 3:338e84e2e558 "move2" (tip)
  merging f and c to c
  merging e and g to g
  saved backup bundle to $TESTTMP/copies/.hg/strip-backup/6e7340ee38c0-ef8ef003-rebase.hg
  $ hg st
  $ hg st --copies --change tip
  A d
    a
  A g
    b
  R b
  $ hg up tip -q
  $ cat c
  c
  c
  $ cat d
  a
  a
  $ cat g
  b
  b
  $ hg log -r . --template "{file_copies}\n"
  d (a)g (b)

Test collapsing a middle revision in-place

  $ hg tglog
  @  2: 64b456429f67 'Collapsed revision
  |  * move1
  |  * move2'
  o  1: 1352765a01d4 'change'
  |
  o  0: f447d5abf5ea 'add'
  
  $ hg rebase --collapse -r 1 -d 0
  abort: cannot rebase changeset with children
  (use --keep to keep original changesets)
  [255]

Test collapsing in place

  $ hg rebase --collapse -b . -d 0
  rebasing 1:1352765a01d4 "change"
  rebasing 2:64b456429f67 "Collapsed revision" (tip)
  saved backup bundle to $TESTTMP/copies/.hg/strip-backup/1352765a01d4-45a352ea-rebase.hg
  $ hg st --change tip --copies
  M a
  M c
  A d
    a
  A g
    b
  R b
  $ hg up tip -q
  $ cat a
  a
  a
  $ cat c
  c
  c
  $ cat d
  a
  a
  $ cat g
  b
  b
  $ cd ..


Test stripping a revision with another child

  $ hg init f
  $ cd f

  $ hg debugdrawdag << 'EOF'
  > C B
  > |/
  > A
  > EOF

  $ hg heads --template="{rev}:{node} {branch}: {desc}\n"
  2:dc0947a82db884575bb76ea10ac97b08536bfa03 default: C
  1:112478962961147124edd43549aedd1a335e44bf default: B

  $ hg strip C
  saved backup bundle to $TESTTMP/f/.hg/strip-backup/dc0947a82db8-d21b92a4-backup.hg

  $ hg tglog
  o  1: 112478962961 'B'
  |
  o  0: 426bada5c675 'A'
  


  $ hg heads --template="{rev}:{node} {branch}: {desc}\n"
  1:112478962961147124edd43549aedd1a335e44bf default: B

  $ cd ..

Test collapsing changes that add then remove a file

  $ hg init collapseaddremove
  $ cd collapseaddremove

  $ touch base
  $ hg commit -Am base
  adding base
  $ touch a
  $ hg commit -Am a
  adding a
  $ hg rm a
  $ touch b
  $ hg commit -Am b
  adding b
  $ hg book foo
  $ hg rebase -d 0 -r "1::2" --collapse -m collapsed
  rebasing 1:6d8d9f24eec3 "a"
  rebasing 2:1cc73eca5ecc "b" (foo tip)
  saved backup bundle to $TESTTMP/collapseaddremove/.hg/strip-backup/6d8d9f24eec3-77d3b6e2-rebase.hg
  $ hg log -G --template "{rev}: '{desc}' {bookmarks}"
  @  1: 'collapsed' foo
  |
  o  0: 'base'
  
  $ hg manifest --rev tip
  b
  base

  $ cd ..

Test that rebase --collapse will remember message after
running into merge conflict and invoking rebase --continue.

  $ hg init collapse_remember_message
  $ cd collapse_remember_message
  $ hg debugdrawdag << 'EOF'
  > C B # B/A = B\n
  > |/  # C/A = C\n
  > A
  > EOF
  $ hg rebase --collapse -m "new message" -b B -d C
  rebasing 1:81e5401e4d37 "B" (B)
  merging A
  warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]
  $ rm A.orig
  $ hg resolve --mark A
  (no more unresolved files)
  continue: hg rebase --continue
  $ hg rebase --continue
  rebasing 1:81e5401e4d37 "B" (B)
  saved backup bundle to $TESTTMP/collapse_remember_message/.hg/strip-backup/81e5401e4d37-96c3dd30-rebase.hg
  $ hg log
  changeset:   2:17186933e123
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     new message
  
  changeset:   1:043039e9df84
  tag:         C
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     C
  
  changeset:   0:426bada5c675
  tag:         A
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     A
  
  $ cd ..

Test aborted editor on final message

  $ HGMERGE=:merge3
  $ export HGMERGE
  $ hg init aborted-editor
  $ cd aborted-editor
  $ hg debugdrawdag << 'EOF'
  > C   # D/A = D\n
  > |   # C/A = C\n
  > B D # B/A = B\n
  > |/  # A/A = A\n
  > A
  > EOF
  $ hg rebase --collapse -t internal:merge3 -s B -d D
  rebasing 1:f899f3910ce7 "B" (B)
  merging A
  warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]
  $ hg tglog
  o  3: 63668d570d21 'C'
  |
  | @  2: 82b8abf9c185 'D'
  | |
  % |  1: f899f3910ce7 'B'
  |/
  o  0: 4a2df7238c3b 'A'
  
  $ cat A
  <<<<<<< dest:   82b8abf9c185 D - test: D
  D
  ||||||| base
  A
  =======
  B
  >>>>>>> source: f899f3910ce7 B - test: B
  $ echo BC > A
  $ hg resolve -m
  (no more unresolved files)
  continue: hg rebase --continue
  $ hg rebase --continue
  rebasing 1:f899f3910ce7 "B" (B)
  rebasing 3:63668d570d21 "C" (C tip)
  merging A
  warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]
  $ hg tglog
  %  3: 63668d570d21 'C'
  |
  | @  2: 82b8abf9c185 'D'
  | |
  o |  1: f899f3910ce7 'B'
  |/
  o  0: 4a2df7238c3b 'A'
  
  $ cat A
  <<<<<<< dest:   82b8abf9c185 D - test: D
  BC
  ||||||| base
  B
  =======
  C
  >>>>>>> source: 63668d570d21 C tip - test: C
  $ echo BD > A
  $ hg resolve -m
  (no more unresolved files)
  continue: hg rebase --continue
  $ HGEDITOR=false hg rebase --continue --config ui.interactive=1
  already rebased 1:f899f3910ce7 "B" (B) as 82b8abf9c185
  rebasing 3:63668d570d21 "C" (C tip)
  abort: edit failed: false exited with status 1
  [255]
  $ hg tglog
  %  3: 63668d570d21 'C'
  |
  | @  2: 82b8abf9c185 'D'
  | |
  o |  1: f899f3910ce7 'B'
  |/
  o  0: 4a2df7238c3b 'A'
  
  $ hg rebase --continue
  already rebased 1:f899f3910ce7 "B" (B) as 82b8abf9c185
  already rebased 3:63668d570d21 "C" (C tip) as 82b8abf9c185
  saved backup bundle to $TESTTMP/aborted-editor/.hg/strip-backup/f899f3910ce7-7cab5e15-rebase.hg