rust-matchers: fix quadratic complexity in `FileMatcher`
Concretely, this command:
```
$ echo hg up -r <nodeid>; time hg revert dir1 dir2 -r <othernode> --debug
hg up -r <nodeid>
real 0m14.690s
user 0m14.766s
sys 0m5.430s
```
was much slower despite using 16 cores before this change.
The approach taken here is the same one used in match.py, in exactmatcher.
This changeset was originally written by Valentin Gatien-Baron in a private
repository.
I have redacted the commit message and did a minor clean up of the code.
import os
from mercurial import (
hg,
scmutil,
ui as uimod,
util,
)
chdir = os.chdir
mkdir = os.mkdir
pjoin = os.path.join
walkrepos = scmutil.walkrepos
checklink = util.checklink
u = uimod.ui.load()
sym = checklink(b'.')
hg.repository(u, b'top1', create=1)
mkdir(b'subdir')
chdir(b'subdir')
hg.repository(u, b'sub1', create=1)
mkdir(b'subsubdir')
chdir(b'subsubdir')
hg.repository(u, b'subsub1', create=1)
chdir(os.path.pardir)
if sym:
os.symlink(os.path.pardir, b'circle')
os.symlink(pjoin(b'subsubdir', b'subsub1'), b'subsub1')
def runtest():
reposet = frozenset(walkrepos(b'.', followsym=True))
if sym and (len(reposet) != 3):
print("reposet = %r" % (reposet,))
print(
(
"Found %d repositories when I should have found 3"
% (len(reposet),)
)
)
if (not sym) and (len(reposet) != 2):
print("reposet = %r" % (reposet,))
print(
(
"Found %d repositories when I should have found 2"
% (len(reposet),)
)
)
sub1set = frozenset(
(pjoin(b'.', b'sub1'), pjoin(b'.', b'circle', b'subdir', b'sub1'))
)
if len(sub1set & reposet) != 1:
print("sub1set = %r" % (sub1set,))
print("reposet = %r" % (reposet,))
print("sub1set and reposet should have exactly one path in common.")
sub2set = frozenset(
(pjoin(b'.', b'subsub1'), pjoin(b'.', b'subsubdir', b'subsub1'))
)
if len(sub2set & reposet) != 1:
print("sub2set = %r" % (sub2set,))
print("reposet = %r" % (reposet,))
print("sub2set and reposet should have exactly one path in common.")
sub3 = pjoin(b'.', b'circle', b'top1')
if sym and sub3 not in reposet:
print("reposet = %r" % (reposet,))
print("Symbolic links are supported and %s is not in reposet" % (sub3,))
runtest()
if sym:
# Simulate not having symlinks.
del os.path.samestat
sym = False
runtest()