view tests/test-copies.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

#testcases filelog compatibility changeset

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > rebase=
  > [alias]
  > l = log -G -T '{rev} {desc}\n{files}\n'
  > EOF

#if compatibility
  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > copies.read-from = compatibility
  > EOF
#endif

#if changeset
  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > copies.read-from = changeset-only
  > copies.write-to = changeset-only
  > EOF
#endif

  $ REPONUM=0
  $ newrepo() {
  >     cd $TESTTMP
  >     REPONUM=`expr $REPONUM + 1`
  >     hg init repo-$REPONUM
  >     cd repo-$REPONUM
  > }

Simple rename case
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x'
  $ hg mv x y
  $ hg debugp1copies
  x -> y
  $ hg debugp2copies
  $ hg ci -m 'rename x to y'
  $ hg l
  @  1 rename x to y
  |  x y
  o  0 add x
     x
  $ hg debugp1copies -r 1
  x -> y
  $ hg debugpathcopies 0 1
  x -> y
  $ hg debugpathcopies 1 0
  y -> x
Test filtering copies by path. We do filtering by destination.
  $ hg debugpathcopies 0 1 x
  $ hg debugpathcopies 1 0 x
  y -> x
  $ hg debugpathcopies 0 1 y
  x -> y
  $ hg debugpathcopies 1 0 y

Copies not including commit changes
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x'
  $ hg mv x y
  $ hg debugpathcopies . .
  $ hg debugpathcopies . 'wdir()'
  x -> y
  $ hg debugpathcopies 'wdir()' .
  y -> x

Copy a file onto another file
  $ newrepo
  $ echo x > x
  $ echo y > y
  $ hg ci -Aqm 'add x and y'
  $ hg cp -f x y
  $ hg debugp1copies
  x -> y
  $ hg debugp2copies
  $ hg ci -m 'copy x onto y'
  $ hg l
  @  1 copy x onto y
  |  y
  o  0 add x and y
     x y
  $ hg debugp1copies -r 1
  x -> y
Incorrectly doesn't show the rename
  $ hg debugpathcopies 0 1

Copy a file onto another file with same content. If metadata is stored in changeset, this does not
produce a new filelog entry. The changeset's "files" entry should still list the file.
  $ newrepo
  $ echo x > x
  $ echo x > x2
  $ hg ci -Aqm 'add x and x2 with same content'
  $ hg cp -f x x2
  $ hg ci -m 'copy x onto x2'
  $ hg l
  @  1 copy x onto x2
  |  x2
  o  0 add x and x2 with same content
     x x2
  $ hg debugp1copies -r 1
  x -> x2
Incorrectly doesn't show the rename
  $ hg debugpathcopies 0 1

Rename file in a loop: x->y->z->x
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x'
  $ hg mv x y
  $ hg debugp1copies
  x -> y
  $ hg debugp2copies
  $ hg ci -m 'rename x to y'
  $ hg mv y z
  $ hg ci -m 'rename y to z'
  $ hg mv z x
  $ hg ci -m 'rename z to x'
  $ hg l
  @  3 rename z to x
  |  x z
  o  2 rename y to z
  |  y z
  o  1 rename x to y
  |  x y
  o  0 add x
     x
  $ hg debugpathcopies 0 3

Copy x to z, then remove z, then copy x2 (same content as x) to z. With copy metadata in the
changeset, the two copies here will have the same filelog entry, so ctx['z'].introrev() might point
to the first commit that added the file. We should still report the copy as being from x2.
  $ newrepo
  $ echo x > x
  $ echo x > x2
  $ hg ci -Aqm 'add x and x2 with same content'
  $ hg cp x z
  $ hg ci -qm 'copy x to z'
  $ hg rm z
  $ hg ci -m 'remove z'
  $ hg cp x2 z
  $ hg ci -m 'copy x2 to z'
  $ hg l
  @  3 copy x2 to z
  |  z
  o  2 remove z
  |  z
  o  1 copy x to z
  |  z
  o  0 add x and x2 with same content
     x x2
  $ hg debugp1copies -r 3
  x2 -> z
  $ hg debugpathcopies 0 3
  x2 -> z

Create x and y, then rename them both to the same name, but on different sides of a fork
  $ newrepo
  $ echo x > x
  $ echo y > y
  $ hg ci -Aqm 'add x and y'
  $ hg mv x z
  $ hg ci -qm 'rename x to z'
  $ hg co -q 0
  $ hg mv y z
  $ hg ci -qm 'rename y to z'
  $ hg l
  @  2 rename y to z
  |  y z
  | o  1 rename x to z
  |/   x z
  o  0 add x and y
     x y
  $ hg debugpathcopies 1 2
  z -> x
  y -> z

Fork renames x to y on one side and removes x on the other
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x'
  $ hg mv x y
  $ hg ci -m 'rename x to y'
  $ hg co -q 0
  $ hg rm x
  $ hg ci -m 'remove x'
  created new head
  $ hg l
  @  2 remove x
  |  x
  | o  1 rename x to y
  |/   x y
  o  0 add x
     x
  $ hg debugpathcopies 1 2

Merge rename from other branch
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x'
  $ hg mv x y
  $ hg ci -m 'rename x to y'
  $ hg co -q 0
  $ echo z > z
  $ hg ci -Aqm 'add z'
  $ hg merge -q 1
  $ hg debugp1copies
  $ hg debugp2copies
  $ hg ci -m 'merge rename from p2'
  $ hg l
  @    3 merge rename from p2
  |\
  | o  2 add z
  | |  z
  o |  1 rename x to y
  |/   x y
  o  0 add x
     x
Perhaps we should indicate the rename here, but `hg status` is documented to be weird during
merges, so...
  $ hg debugp1copies -r 3
  $ hg debugp2copies -r 3
  $ hg debugpathcopies 0 3
  x -> y
  $ hg debugpathcopies 1 2
  y -> x
  $ hg debugpathcopies 1 3
  $ hg debugpathcopies 2 3
  x -> y

Copy file from either side in a merge
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x'
  $ hg co -q null
  $ echo y > y
  $ hg ci -Aqm 'add y'
  $ hg merge -q 0
  $ hg cp y z
  $ hg debugp1copies
  y -> z
  $ hg debugp2copies
  $ hg ci -m 'copy file from p1 in merge'
  $ hg co -q 1
  $ hg merge -q 0
  $ hg cp x z
  $ hg debugp1copies
  $ hg debugp2copies
  x -> z
  $ hg ci -qm 'copy file from p2 in merge'
  $ hg l
  @    3 copy file from p2 in merge
  |\   z
  +---o  2 copy file from p1 in merge
  | |/   z
  | o  1 add y
  |    y
  o  0 add x
     x
  $ hg debugp1copies -r 2
  y -> z
  $ hg debugp2copies -r 2
  $ hg debugpathcopies 1 2
  y -> z
  $ hg debugpathcopies 0 2
  $ hg debugp1copies -r 3
  $ hg debugp2copies -r 3
  x -> z
  $ hg debugpathcopies 1 3
  $ hg debugpathcopies 0 3
  x -> z

Copy file that exists on both sides of the merge, same content on both sides
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x on branch 1'
  $ hg co -q null
  $ echo x > x
  $ hg ci -Aqm 'add x on branch 2'
  $ hg merge -q 0
  $ hg cp x z
  $ hg debugp1copies
  x -> z
  $ hg debugp2copies
  $ hg ci -qm 'merge'
  $ hg l
  @    2 merge
  |\   z
  | o  1 add x on branch 2
  |    x
  o  0 add x on branch 1
     x
  $ hg debugp1copies -r 2
  x -> z
  $ hg debugp2copies -r 2
It's a little weird that it shows up on both sides
  $ hg debugpathcopies 1 2
  x -> z
  $ hg debugpathcopies 0 2
  x -> z (filelog !)

Copy file that exists on both sides of the merge, different content
  $ newrepo
  $ echo branch1 > x
  $ hg ci -Aqm 'add x on branch 1'
  $ hg co -q null
  $ echo branch2 > x
  $ hg ci -Aqm 'add x on branch 2'
  $ hg merge -q 0
  warning: conflicts while merging x! (edit, then use 'hg resolve --mark')
  [1]
  $ echo resolved > x
  $ hg resolve -m x
  (no more unresolved files)
  $ hg cp x z
  $ hg debugp1copies
  x -> z
  $ hg debugp2copies
  $ hg ci -qm 'merge'
  $ hg l
  @    2 merge
  |\   x z
  | o  1 add x on branch 2
  |    x
  o  0 add x on branch 1
     x
  $ hg debugp1copies -r 2
  x -> z (changeset !)
  $ hg debugp2copies -r 2
  x -> z (no-changeset !)
  $ hg debugpathcopies 1 2
  x -> z (changeset !)
  $ hg debugpathcopies 0 2
  x -> z (no-changeset !)

Copy x->y on one side of merge and copy x->z on the other side. Pathcopies from one parent
of the merge to the merge should include the copy from the other side.
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x'
  $ hg cp x y
  $ hg ci -qm 'copy x to y'
  $ hg co -q 0
  $ hg cp x z
  $ hg ci -qm 'copy x to z'
  $ hg merge -q 1
  $ hg ci -m 'merge copy x->y and copy x->z'
  $ hg l
  @    3 merge copy x->y and copy x->z
  |\
  | o  2 copy x to z
  | |  z
  o |  1 copy x to y
  |/   y
  o  0 add x
     x
  $ hg debugp1copies -r 3
  $ hg debugp2copies -r 3
  $ hg debugpathcopies 2 3
  x -> y
  $ hg debugpathcopies 1 3
  x -> z

Copy x to y on one side of merge, create y and rename to z on the other side.
  $ newrepo
  $ echo x > x
  $ hg ci -Aqm 'add x'
  $ hg cp x y
  $ hg ci -qm 'copy x to y'
  $ hg co -q 0
  $ echo y > y
  $ hg ci -Aqm 'add y'
  $ hg mv y z
  $ hg ci -m 'rename y to z'
  $ hg merge -q 1
  $ hg ci -m 'merge'
  $ hg l
  @    4 merge
  |\
  | o  3 rename y to z
  | |  y z
  | o  2 add y
  | |  y
  o |  1 copy x to y
  |/   y
  o  0 add x
     x
  $ hg debugp1copies -r 3
  y -> z
  $ hg debugp2copies -r 3
  $ hg debugpathcopies 2 3
  y -> z
  $ hg debugpathcopies 1 3
  y -> z (no-filelog !)

Create x and y, then rename x to z on one side of merge, and rename y to z and
modify z on the other side. When storing copies in the changeset, we don't
filter out copies whose target was created on the other side of the merge.
  $ newrepo
  $ echo x > x
  $ echo y > y
  $ hg ci -Aqm 'add x and y'
  $ hg mv x z
  $ hg ci -qm 'rename x to z'
  $ hg co -q 0
  $ hg mv y z
  $ hg ci -qm 'rename y to z'
  $ echo z >> z
  $ hg ci -m 'modify z'
  $ hg merge -q 1
  warning: conflicts while merging z! (edit, then use 'hg resolve --mark')
  [1]
  $ echo z > z
  $ hg resolve -qm z
  $ hg ci -m 'merge 1 into 3'
Try merging the other direction too
  $ hg co -q 1
  $ hg merge -q 3
  warning: conflicts while merging z! (edit, then use 'hg resolve --mark')
  [1]
  $ echo z > z
  $ hg resolve -qm z
  $ hg ci -m 'merge 3 into 1'
  created new head
  $ hg l
  @    5 merge 3 into 1
  |\   z
  +---o  4 merge 1 into 3
  | |/   z
  | o  3 modify z
  | |  z
  | o  2 rename y to z
  | |  y z
  o |  1 rename x to z
  |/   x z
  o  0 add x and y
     x y
  $ hg debugpathcopies 1 4
  y -> z (no-filelog !)
  $ hg debugpathcopies 2 4
  x -> z (no-filelog !)
  $ hg debugpathcopies 0 4
  x -> z (filelog !)
  y -> z (compatibility !)
  y -> z (changeset !)
  $ hg debugpathcopies 1 5
  y -> z (no-filelog !)
  $ hg debugpathcopies 2 5
  x -> z (no-filelog !)
  $ hg debugpathcopies 0 5
  x -> z


Test for a case in fullcopytracing algorithm where neither of the merging csets
is a descendant of the merge base. This test reflects that the algorithm
correctly finds the copies:

  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > evolution.createmarkers=True
  > evolution.allowunstable=True
  > EOF

  $ newrepo
  $ echo a > a
  $ hg add a
  $ hg ci -m "added a"
  $ echo b > b
  $ hg add b
  $ hg ci -m "added b"

  $ hg mv b b1
  $ hg ci -m "rename b to b1"

  $ hg up ".^"
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo d > d
  $ hg add d
  $ hg ci -m "added d"
  created new head

  $ echo baba >> b
  $ hg ci --amend -m "added d, modified b"

  $ hg l --hidden
  @  4 added d, modified b
  |  b d
  | x  3 added d
  |/   d
  | o  2 rename b to b1
  |/   b b1
  o  1 added b
  |  b
  o  0 added a
     a

Grafting revision 4 on top of revision 2, showing that it respect the rename:

  $ hg up 2 -q
  $ hg graft -r 4 --base 3 --hidden
  grafting 4:af28412ec03c "added d, modified b" (tip) (no-changeset !)
  grafting 4:6325ca0b7a1c "added d, modified b" (tip) (changeset !)
  merging b1 and b to b1

  $ hg l -l1 -p
  @  5 added d, modified b
  |  b1
  ~  diff -r 5a4825cc2926 -r 94a2f1a0e8e2 b1 (no-changeset !)
  ~  diff -r 0a0ed3b3251c -r d544fb655520 b1 (changeset !)
     --- a/b1	Thu Jan 01 00:00:00 1970 +0000
     +++ b/b1	Thu Jan 01 00:00:00 1970 +0000
     @@ -1,1 +1,2 @@
      b
     +baba
  
Test to make sure that fullcopytracing algorithm doesn't fail when neither of the
merging csets is a descendant of the base.
-------------------------------------------------------------------------------------------------

  $ newrepo
  $ echo a > a
  $ hg add a
  $ hg ci -m "added a"
  $ echo b > b
  $ hg add b
  $ hg ci -m "added b"

  $ echo foobar > willconflict
  $ hg add willconflict
  $ hg ci -m "added willconflict"
  $ echo c > c
  $ hg add c
  $ hg ci -m "added c"

  $ hg l
  @  3 added c
  |  c
  o  2 added willconflict
  |  willconflict
  o  1 added b
  |  b
  o  0 added a
     a

  $ hg up ".^^"
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo d > d
  $ hg add d
  $ hg ci -m "added d"
  created new head

  $ echo barfoo > willconflict
  $ hg add willconflict
  $ hg ci --amend -m "added willconflict and d"

  $ hg l
  @  5 added willconflict and d
  |  d willconflict
  | o  3 added c
  | |  c
  | o  2 added willconflict
  |/   willconflict
  o  1 added b
  |  b
  o  0 added a
     a

  $ hg rebase -r . -d 2 -t :other
  rebasing 5:5018b1509e94 "added willconflict and d" (tip) (no-changeset !)
  rebasing 5:af8d273bf580 "added willconflict and d" (tip) (changeset !)

  $ hg up 3 -q
  $ hg l --hidden
  o  6 added willconflict and d
  |  d willconflict
  | x  5 added willconflict and d
  | |  d willconflict
  | | x  4 added d
  | |/   d
  +---@  3 added c
  | |    c
  o |  2 added willconflict
  |/   willconflict
  o  1 added b
  |  b
  o  0 added a
     a

Now if we trigger a merge between revision 3 and 6 using base revision 4,
neither of the merging csets will be a descendant of the base revision:

  $ hg graft -r 6 --base 4 --hidden -t :other
  grafting 6:99802e4f1e46 "added willconflict and d" (tip) (no-changeset !)
  grafting 6:b19f0df72728 "added willconflict and d" (tip) (changeset !)