tags-cache: skip the filternode step if we are not going to use it
When warming the hgtagsfnodescache, we don't need the actual result, so we can
simply skip the part that "filter" fnode we read from the cache. So provide a
quite visible speed up to the top level `hg debugupdatecache` function.
### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
# benchmark.name = hg.debug.debug-update-cache
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.pre-state = warm
before: 19.947581
after: 18.916804 (-5.17%, -1.03)
#require no-symlink
# The following script was used to create the bundle:
#
# hg init symlinks
# cd symlinks
# echo a > a
# mkdir d
# echo b > d/b
# ln -s a a.lnk
# ln -s d/b d/b.lnk
# hg ci -Am t
# hg bundle --base null ../test-no-symlinks.hg
Extract a symlink on a platform not supporting them
$ hg init t
$ cd t
$ hg pull -q "$TESTDIR/bundles/test-no-symlinks.hg"
$ hg update
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat a.lnk && echo
a
$ cat d/b.lnk && echo
d/b
Copy a symlink and move another
$ hg copy a.lnk d/a2.lnk
$ hg mv d/b.lnk b2.lnk
$ hg ci -Am copy
$ cat d/a2.lnk && echo
a
$ cat b2.lnk && echo
d/b
Bundle and extract again
$ hg bundle --base null ../symlinks.hg
2 changesets found
$ cd ..
$ hg init t2
$ cd t2
$ hg pull ../symlinks.hg
pulling from ../symlinks.hg
requesting all changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 6 changes to 6 files
new changesets d326ae2d01ee:71d85cf3ba90 (2 drafts)
(run 'hg update' to get a working copy)
$ hg update
5 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat a.lnk && echo
a
$ cat d/a2.lnk && echo
a
$ cat b2.lnk && echo
d/b