status: prefer relative paths in Rust code
… when the repository root is under the current directory,
so the kernel needs to traverse fewer directory in every call
to `read_dir` or `symlink_metadata`.
Better yet would be to use libc functions like `openat` and `fstatat`
to remove such repeated traversals entirely, but the standard library
does not provide APIs based on those.
Maybe with a crate like https://crates.io/crates/openat instead?
Benchmarks of `rhg status` show that this patch is neutral in some configurations,
and makes the command up to ~20% faster in others.
Below is semi-arbitrary subset of results. The four numeric columns are:
time (in seconds) with this changeset’s parent, time with this changeset,
time difference (negative is better), time ratio (less than 1 is better).
```
mercurial-dirstate-v1 | default-plain-clean.no-iu.pbr | 0.0061 -> 0.0059: -0.0002 (0.97)
mercurial-dirstate-v2 | default-plain-clean.no-iu.pbr | 0.0029 -> 0.0028: -0.0001 (0.97)
mozilla-dirstate-v1 | default-plain-clean.no-iu.pbr | 0.2110 -> 0.2102: -0.0007 (1.00)
mozilla-dirstate-v2 | default-copies-clean.ignored.pbr | 0.0489 -> 0.0401: -0.0088 (0.82)
mozilla-dirstate-v2 | default-copies-clean.no-iu.pbr | 0.0479 -> 0.0393: -0.0085 (0.82)
mozilla-dirstate-v2 | default-copies-large.all.pbr | 0.1262 -> 0.1210: -0.0051 (0.96)
mozilla-dirstate-v2 | default-copies-small.ignored-unknown.pbr | 0.1262 -> 0.1200: -0.0062 (0.95)
mozilla-dirstate-v2 | default-copies-small.ignored.pbr | 0.0536 -> 0.0417: -0.0119 (0.78)
mozilla-dirstate-v2 | default-copies-small.no-iu.pbr | 0.0482 -> 0.0393: -0.0089 (0.81)
mozilla-dirstate-v2 | default-plain-clean.ignored.pbr | 0.0518 -> 0.0402: -0.0116 (0.78)
mozilla-dirstate-v2 | default-plain-clean.no-iu.pbr | 0.0481 -> 0.0392: -0.0088 (0.82)
mozilla-dirstate-v2 | default-plain-large.all.pbr | 0.1271 -> 0.1218: -0.0052 (0.96)
mozilla-dirstate-v2 | default-plain-small.ignored-unknown.pbr | 0.1225 -> 0.1202: -0.0022 (0.98)
mozilla-dirstate-v2 | default-plain-small.ignored.pbr | 0.0510 -> 0.0418: -0.0092 (0.82)
mozilla-dirstate-v2 | default-plain-small.no-iu.pbr | 0.0480 -> 0.0394: -0.0086 (0.82)
netbeans-dirstate-v1 | default-plain-clean.no-iu.pbr | 0.1442 -> 0.1422: -0.0020 (0.99)
netbeans-dirstate-v2 | default-plain-clean.no-iu.pbr | 0.0325 -> 0.0282: -0.0043 (0.87)
```
Differential Revision: https://phab.mercurial-scm.org/D12175
$ cat > adddrop.py <<EOF
> from mercurial import registrar
> cmdtable = {}
> command = registrar.command(cmdtable)
> @command(b'debugadddrop',
> [(b'', b'drop', False, b'drop file from dirstate', b'FILE'),
> (b'', b'normal-lookup', False, b'add file to dirstate', b'FILE')],
> b'hg debugadddrop')
> def debugadddrop(ui, repo, *pats, **opts):
> '''Add or drop unnamed arguments to or from the dirstate'''
> drop = opts.get('drop')
> nl = opts.get('normal_lookup')
> if nl and drop:
> raise error.Abort('drop and normal-lookup are mutually exclusive')
> wlock = repo.wlock()
> try:
> for file in pats:
> if opts.get('normal_lookup'):
> with repo.dirstate.parentchange():
> repo.dirstate.update_file(
> file,
> p1_tracked=True,
> wc_tracked=True,
> possibly_dirty=True,
> )
> else:
> repo.dirstate._map.reset_state(file)
> repo.dirstate._dirty = True
>
> repo.dirstate.write(repo.currenttransaction())
> finally:
> wlock.release()
> EOF
$ echo "[extensions]" >> $HGRCPATH
$ echo "debugadddrop=`pwd`/adddrop.py" >> $HGRCPATH
basic test for hg debugrebuildstate
$ hg init repo
$ cd repo
$ touch foo bar
$ hg ci -Am 'add foo bar'
adding bar
adding foo
$ touch baz
$ hg add baz
$ hg rm bar
$ hg debugrebuildstate
state dump after
$ hg debugstate --no-dates | sort
n 0 -1 unset bar
n 0 -1 unset foo
$ hg debugadddrop --normal-lookup file1 file2
$ hg debugadddrop --drop bar
$ hg debugadddrop --drop
$ hg debugstate --no-dates
n 0 -1 unset file1
n 0 -1 unset file2
n 0 -1 unset foo
$ hg debugrebuildstate
status
$ hg st -A
! bar
? baz
C foo
Test debugdirstate --minimal where a file is not in parent manifest
but in the dirstate
$ touch foo bar qux
$ hg add qux
$ hg remove bar
$ sleep 1 # remove potential ambiguity in mtime
$ hg status -A
A qux
R bar
? baz
C foo
$ hg debugadddrop --normal-lookup baz
$ hg debugdirstate --no-dates
r 0 0 * bar (glob)
n 0 -1 * baz (glob)
n 644 0 * foo (glob)
a 0 -1 * qux (glob)
$ hg debugrebuilddirstate --minimal
$ hg debugdirstate --no-dates
r 0 0 * bar (glob)
n 644 0 * foo (glob)
a 0 -1 * qux (glob)
$ hg status -A
A qux
R bar
? baz
C foo
Test debugdirstate --minimal where file is in the parent manifest but not the
dirstate
$ hg manifest
bar
foo
$ sleep 1 # remove potential ambiguity in mtime
$ hg status -A
A qux
R bar
? baz
C foo
$ hg debugdirstate --no-dates
r 0 0 * bar (glob)
n 644 0 * foo (glob)
a 0 -1 * qux (glob)
$ hg debugadddrop --drop foo
$ hg debugdirstate --no-dates
r 0 0 * bar (glob)
a 0 -1 * qux (glob)
$ hg debugrebuilddirstate --minimal
$ hg debugdirstate --no-dates
r 0 0 * bar (glob)
n 0 -1 * foo (glob)
a 0 -1 * qux (glob)
$ hg status -A
A qux
R bar
? baz
C foo