outgoing: rework the handling of the `missingroots` case to be faster
The previous implementation was slow, to the point it was taking a significant
amount of `hg bundle --type none-streamv2` call. We rework the code to compute
the same value much faster, making the operation disappear from the `hg bundle
--type none-streamv2` profile. Someone would remark that producing a streamclone
does not requires an `outgoing` object. However that is a matter for another
day. There is other user of `missingroots` (non stream `hg bundle` call for
example), and they will also benefit from this rework.
We implement an old TODO in the process, directly computing the missing and
common attribute as we have most element at hand already.
### benchmark.name = hg.command.bundle
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.revs = all
# benchmark.variants.type = none-streamv2
## data-env-vars.name = heptapod-public-2024-03-25-zstd-sparse-revlog
before: 7.750458
after: 6.665565 (-14.00%, -1.08)
## data-env-vars.name = mercurial-public-2024-03-22-zstd-sparse-revlog
before: 0.700229
after: 0.496050 (-29.16%, -0.20)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
before: 346.508952
after: 316.749699 (-8.59%, -29.76)
## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog
before: 3.401700
after: 2.915810 (-14.28%, -0.49)
## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog
before: 1.870798
after: 1.461583 (-21.87%, -0.41)
note: this whole `missingroots` of outgoing has a limited number of callers and
could likely be replace by something simpler (like taking an explicit
"missing_revs" set for example). However this is a wider change and we focus on
a small impact, quick rework that does not change the API for now.
$ cat >> $HGRCPATH << EOF
> [extensions]
> show =
> EOF
$ hg init repo0
$ cd repo0
Empty repo / no checkout results in error
$ hg show stack
abort: stack view only available when there is a working directory
[255]
Stack displays single draft changeset as root revision
$ echo 0 > foo
$ hg -q commit -A -m 'commit 0'
$ hg show stack
@ 9f17 commit 0
Stack displays multiple draft changesets
$ echo 1 > foo
$ hg commit -m 'commit 1'
$ echo 2 > foo
$ hg commit -m 'commit 2'
$ echo 3 > foo
$ hg commit -m 'commit 3'
$ echo 4 > foo
$ hg commit -m 'commit 4'
$ hg show stack
@ 2737 commit 4
o d1a6 commit 3
o 128c commit 2
o 181c commit 1
o 9f17 commit 0
Public parent of draft base is displayed, separated from stack
$ hg phase --public -r 0
$ hg show stack
@ 2737 commit 4
o d1a6 commit 3
o 128c commit 2
o 181c commit 1
/ (stack base)
o 9f17 commit 0
$ hg phase --public -r 1
$ hg show stack
@ 2737 commit 4
o d1a6 commit 3
o 128c commit 2
/ (stack base)
o 181c commit 1
Draft descendants are shown
$ hg -q up 2
$ hg show stack
o 2737 commit 4
o d1a6 commit 3
@ 128c commit 2
/ (stack base)
o 181c commit 1
$ hg -q up 3
$ hg show stack
o 2737 commit 4
@ d1a6 commit 3
o 128c commit 2
/ (stack base)
o 181c commit 1
working dir on public changeset should display special message
$ hg -q up 1
$ hg show stack
(empty stack; working directory parent is a published changeset)
Branch point in descendants displayed at top of graph
$ hg -q up 3
$ echo b > foo
$ hg commit -m 'commit 5 (new dag branch)'
created new head
$ hg -q up 2
$ hg show stack
\ / (multiple children)
|
o d1a6 commit 3
@ 128c commit 2
/ (stack base)
o 181c commit 1
$ cd ..
Base is stopped at merges
$ hg init merge-base
$ cd merge-base
$ echo 0 > foo
$ hg -q commit -A -m initial
$ echo h1 > foo
$ hg commit -m 'head 1'
$ hg -q up 0
$ echo h2 > foo
$ hg -q commit -m 'head 2'
$ hg phase --public -r 0:tip
$ hg -q up 1
$ hg merge -t :local 2
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m 'merge heads'
TODO doesn't yet handle case where wdir is a draft merge
$ hg show stack
@ 8ee9 merge heads
/ (stack base)
o 5947 head 1
$ echo d1 > foo
$ hg commit -m 'draft 1'
$ echo d2 > foo
$ hg commit -m 'draft 2'
$ hg show stack
@ 430d draft 2
o 787b draft 1
/ (stack base)
o 8ee9 merge heads
$ cd ..
Now move on to stacks when there are more commits after the base branchpoint
$ hg init public-rebase
$ cd public-rebase
$ echo 0 > foo
$ hg -q commit -A -m 'base'
$ hg phase --public -r .
$ echo d1 > foo
$ hg commit -m 'draft 1'
$ echo d2 > foo
$ hg commit -m 'draft 2'
$ hg -q up 0
$ echo 1 > foo
$ hg commit -m 'new 1'
created new head
$ echo 2 > foo
$ hg commit -m 'new 2'
$ hg -q up 2
Newer draft heads don't impact output
$ hg show stack
@ eaff draft 2
o 2b21 draft 1
/ (stack base)
o b66b base
Newer public heads are rendered
$ hg phase --public -r '::tip'
$ hg show stack
o baa4 new 2
/ (2 commits ahead)
:
: (stack head)
: @ eaff draft 2
: o 2b21 draft 1
:/ (stack base)
o b66b base
If rebase is available, we show a hint how to rebase to that head
$ hg --config extensions.rebase= show stack
o baa4 new 2
/ (2 commits ahead; hg rebase --source 2b21 --dest baa4)
:
: (stack head)
: @ eaff draft 2
: o 2b21 draft 1
:/ (stack base)
o b66b base
Similar tests but for multiple heads
$ hg -q up 0
$ echo h2 > foo
$ hg -q commit -m 'new head 2'
$ hg phase --public -r .
$ hg -q up 2
$ hg show stack
o baa4 new 2
/ (2 commits ahead)
: o 9a84 new head 2
:/ (1 commits ahead)
:
: (stack head)
: @ eaff draft 2
: o 2b21 draft 1
:/ (stack base)
o b66b base
$ hg --config extensions.rebase= show stack
o baa4 new 2
/ (2 commits ahead; hg rebase --source 2b21 --dest baa4)
: o 9a84 new head 2
:/ (1 commits ahead; hg rebase --source 2b21 --dest 9a84)
:
: (stack head)
: @ eaff draft 2
: o 2b21 draft 1
:/ (stack base)
o b66b base