tags-cache: directly perform a monimal walk for hgtagsfnodescache warming We do something narrower than the path retrieving data. So lets use dedicated code instead. This provides further useful speedup: ### 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-this-series: 19.947581 skip-fnode-filter: 18.916804 (-5.17%, -1.03) use-rev-num: 17.493725 (-12.30%, -2.45) this-changesets: 15.919466 (-20.19%, -4.03)

import unittest

import silenttestrunner

from mercurial import pathutil


class dirstests(unittest.TestCase):
    def testdirs(self):
        for case, want in [
            (b'a/a/a', [b'a', b'a/a', b'']),
            (b'alpha/beta/gamma', [b'', b'alpha', b'alpha/beta']),
        ]:
            d = pathutil.dirs([])
            d.addpath(case)
            self.assertEqual(sorted(d), sorted(want))

    def testinvalid(self):
        with self.assertRaises(ValueError):
            d = pathutil.dirs([])
            d.addpath(b'a//b')


if __name__ == '__main__':
    silenttestrunner.main(__name__)