revset: stop serializing node when using "%ln"
Turning hundred of thousand of node from node to hex and back can be slow… what
about we stop doing it?
In many case were we are using node id we should be using revision id. However
this is not a good reason to have a stupidly slow implementation of "%ln".
This caught my attention again because the phase discovery during push make an
extensive use of "%ln" or huge set. In absolute, that phase discovery probably
should use "%ld" and need to improves its algorithmic complexity, but improving
"%ln" seems simple and long overdue. This greatly speeds up `hg push` on
repository with many drafts.
Here are some relevant poulpe benchmarks:
### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
# benchmark.name = hg.command.push
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.explicit-rev = all-out-heads
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.reuse-external-delta-parent = default
## benchmark.variants.revs = any-1-extra-rev
before: 44.235070
after: 20.416329 (-53.85%, -23.82)
## benchmark.variants.revs = any-100-extra-rev
before: 49.234697
after: 26.519829 (-46.14%, -22.71)
### 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: 10.138396
after: 7.750458 (-23.55%, -2.39)
## data-env-vars.name = mercurial-public-2024-03-22-zstd-sparse-revlog
before: 1.263859
after: 0.700229 (-44.60%, -0.56)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
before: 399.484481
after: 346.5089 (-13.26%, -52.98)
## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog
before: 4.540080
after: 3.401700 (-25.07%, -1.14)
## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog
before: 2.975765
after: 1.870798 (-37.13%, -1.10)
Tests about metadataonlyctx
$ hg init
$ echo A > A
$ hg commit -A A -m 'Add A'
$ echo B > B
$ hg commit -A B -m 'Add B'
$ hg rm A
$ echo C > C
$ echo B2 > B
$ hg add C -q
$ hg commit -m 'Remove A'
$ cat > metaedit.py <<EOF
> from mercurial import context, pycompat, registrar
> cmdtable = {}
> command = registrar.command(cmdtable)
> @command(b'metaedit')
> def metaedit(ui, repo, arg):
> # Modify commit message to "FOO"
> with repo.wlock(), repo.lock(), repo.transaction(b'metaedit'):
> old = repo[b'.']
> kwargs = dict(s.split(b'=', 1) for s in arg.split(b';'))
> if b'parents' in kwargs:
> kwargs[b'parents'] = map(int, kwargs[b'parents'].split(b','))
> new = context.metadataonlyctx(repo, old,
> **pycompat.strkwargs(kwargs))
> new.commit()
> EOF
$ hg --config extensions.metaedit=$TESTTMP/metaedit.py metaedit 'text=Changed'
$ hg log -r tip
changeset: 3:ad83e9e00ec9
tag: tip
parent: 1:3afb7afe6632
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Changed
$ hg --config extensions.metaedit=$TESTTMP/metaedit.py metaedit 'parents=0' 2>&1 | grep -E '^RuntimeError'
RuntimeError: can't reuse the manifest: its p1 doesn't match the new ctx p1
$ hg --config extensions.metaedit=$TESTTMP/metaedit.py metaedit 'user=foo <foo@example.com>'
$ hg log -r tip
changeset: 4:1f86eaeca92b
tag: tip
parent: 1:3afb7afe6632
user: foo <foo@example.com>
date: Thu Jan 01 00:00:00 1970 +0000
summary: Remove A