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.
https://bz.mercurial-scm.org/1175
$ hg init repo
$ cd repo
$ touch a
$ hg ci -Am0
adding a
$ hg mv a a1
$ hg ci -m1
$ hg co 0
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg mv a a2
$ hg up
note: possible conflict - a was renamed multiple times to:
a1
a2
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg ci -m2
$ touch a
$ hg ci -Am3
adding a
$ hg mv a b
$ hg ci -Am4 a
$ hg ci --debug --traceback -Am5 b
committing files:
b
warning: can't find ancestor for 'b' copied from 'a'!
committing manifest
committing changelog
updating the branch cache
committed changeset 5:83a687e8a97c80992ba385bbfd766be181bfb1d1
$ hg verify -q
$ hg export --git tip
# HG changeset patch
# User test
# Date 0 0
# Thu Jan 01 00:00:00 1970 +0000
# Node ID 83a687e8a97c80992ba385bbfd766be181bfb1d1
# Parent 1d1625283f71954f21d14c3d44d0ad3c019c597f
5
diff --git a/b b/b
new file mode 100644
https://bz.mercurial-scm.org/show_bug.cgi?id=4476
$ hg init foo
$ cd foo
$ touch a && hg ci -Aqm a
$ hg mv a b
$ echo b1 >> b
$ hg ci -Aqm b1
$ hg up 0
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg mv a b
$ echo b2 >> b
$ hg ci -Aqm b2
$ hg graft 1
grafting 1:5974126fad84 "b1"
merging b
warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
abort: unresolved conflicts, can't continue
(use 'hg resolve' and 'hg graft --continue')
[1]
$ echo a > b
$ echo b3 >> b
$ hg resolve --mark b
(no more unresolved files)
continue: hg graft --continue
$ hg graft --continue
grafting 1:5974126fad84 "b1"
$ hg log -f b -T 'changeset: {rev}:{node|short}\nsummary: {desc}\n\n'
changeset: 3:376d30ccffc0
summary: b1
changeset: 2:416baaa2e5e4
summary: b2
changeset: 0:3903775176ed
summary: a