view mercurial/sparse.py @ 46568:0d840b9d200d

copies-rust: track "overwrites" directly within CopySource Overwrite are "rare enough" that explicitly keeping track of them is going to be "cheap", or at least much cheaper that issuing many `is_ancestor` calls. Even a simple implementation using no specific optimisation (eg: using the generic HashSet type) yield good result in most cases. They are interesting optimization to can do on top of that. We will implement them in later changesets. We tried different approach to speed up the overwrite detection and this one seems the most promising. Without further optimization, we already see sizable speedup on various cases. Repo Case Source-Rev Dest-Rev # of revisions old time new time Difference Factor time per rev --------------------------------------------------------------------------------------------------------------------------------------------------------------- mozilla-try x00000_revs_x_added_0_copies 6a320851d377 1ebb79acd503 : 363753 revs, 5.138169 s, 4.482399 s, -0.655770 s, × 0.8724, 12 µs/rev mozilla-try x00000_revs_x_added_x_copies 5173c4b6f97c 95d83ee7242d : 362229 revs, 5.127809 s, 4.480366 s, -0.647443 s, × 0.8737, 12 µs/rev mozilla-try x00000_revs_x000_added_x_copies 9126823d0e9c ca82787bb23c : 359344 revs, 4.971136 s, 4.369070 s, -0.602066 s, × 0.8789, 12 µs/rev mozilla-try x00000_revs_x0000_added_x0000_copies 8d3fafa80d4b eb884023b810 : 192665 revs, 1.741678 s, 1.592506 s, -0.149172 s, × 0.9144, 8 µs/rev However, some of the case doing a lot of overwrite get significantly slower. The one with a really problematic slowdown are the special "head reducing" merge in mozilla-try so I am not too worried about them. In addition, further changeset are going to improve the performance of all this. Repo Case Source-Rev Dest-Rev # of revisions old time new time Difference Factor time per rev --------------------------------------------------------------------------------------------------------------------------------------------------------------- mozilla-try x0000_revs_xx000_added_x000_copies 89294cd501d9 7ccb2fc7ccb5 : 97052 revs, 1.343373 s, 2.119204 s, +0.775831 s, × 1.5775, 21 µs/rev mozilla-try x00000_revs_x00000_added_x0000_copies 1b661134e2ca 1ae03d022d6d : 228985 revs, 40.314822 s, 87.824489 s, +47.509667 s, × 2.1785, 383 µs/rev mozilla-try x00000_revs_x00000_added_x000_copies 9b2a99adc05e 8e29777b48e6 : 382065 revs, 20.048029 s, 43.304637 s, +23.256608 s, × 2.1600, 113 µs/rev Full benchmark below: Repo Case Source-Rev Dest-Rev # of revisions old time new time Difference Factor time per rev --------------------------------------------------------------------------------------------------------------------------------------------------------------- mercurial x_revs_x_added_0_copies ad6b123de1c7 39cfcef4f463 : 1 revs, 0.000042 s, 0.000043 s, +0.000001 s, × 1.0238, 43 µs/rev mercurial x_revs_x_added_x_copies 2b1c78674230 0c1d10351869 : 6 revs, 0.000110 s, 0.000114 s, +0.000004 s, × 1.0364, 19 µs/rev mercurial x000_revs_x000_added_x_copies 81f8ff2a9bf2 dd3267698d84 : 1032 revs, 0.004945 s, 0.004937 s, -0.000008 s, × 0.9984, 4 µs/rev pypy x_revs_x_added_0_copies aed021ee8ae8 099ed31b181b : 9 revs, 0.000192 s, 0.000339 s, +0.000147 s, × 1.7656, 37 µs/rev pypy x_revs_x000_added_0_copies 4aa4e1f8e19a 359343b9ac0e : 1 revs, 0.000049 s, 0.000049 s, +0.000000 s, × 1.0000, 49 µs/rev pypy x_revs_x_added_x_copies ac52eb7bbbb0 72e022663155 : 7 revs, 0.000112 s, 0.000202 s, +0.000090 s, × 1.8036, 28 µs/rev pypy x_revs_x00_added_x_copies c3b14617fbd7 ace7255d9a26 : 1 revs, 0.000323 s, 0.000409 s, +0.000086 s, × 1.2663, 409 µs/rev pypy x_revs_x000_added_x000_copies df6f7a526b60 a83dc6a2d56f : 6 revs, 0.010042 s, 0.011984 s, +0.001942 s, × 1.1934, 1997 µs/rev pypy x000_revs_xx00_added_0_copies 89a76aede314 2f22446ff07e : 4785 revs, 0.049813 s, 0.050820 s, +0.001007 s, × 1.0202, 10 µs/rev pypy x000_revs_x000_added_x_copies 8a3b5bfd266e 2c68e87c3efe : 6780 revs, 0.079937 s, 0.087953 s, +0.008016 s, × 1.1003, 12 µs/rev pypy x000_revs_x000_added_x000_copies 89a76aede314 7b3dda341c84 : 5441 revs, 0.059412 s, 0.062902 s, +0.003490 s, × 1.0587, 11 µs/rev pypy x0000_revs_x_added_0_copies d1defd0dc478 c9cb1334cc78 : 43645 revs, 0.533769 s, 0.679234 s, +0.145465 s, × 1.2725, 15 µs/rev pypy x0000_revs_xx000_added_0_copies bf2c629d0071 4ffed77c095c : 2 revs, 0.013147 s, 0.013095 s, -0.000052 s, × 0.9960, 6547 µs/rev pypy x0000_revs_xx000_added_x000_copies 08ea3258278e d9fa043f30c0 : 11316 revs, 0.110680 s, 0.120910 s, +0.010230 s, × 1.0924, 10 µs/rev netbeans x_revs_x_added_0_copies fb0955ffcbcd a01e9239f9e7 : 2 revs, 0.000085 s, 0.000087 s, +0.000002 s, × 1.0235, 43 µs/rev netbeans x_revs_x000_added_0_copies 6f360122949f 20eb231cc7d0 : 2 revs, 0.000107 s, 0.000107 s, +0.000000 s, × 1.0000, 53 µs/rev netbeans x_revs_x_added_x_copies 1ada3faf6fb6 5a39d12eecf4 : 3 revs, 0.000175 s, 0.000186 s, +0.000011 s, × 1.0629, 62 µs/rev netbeans x_revs_x00_added_x_copies 35be93ba1e2c 9eec5e90c05f : 9 revs, 0.000720 s, 0.000754 s, +0.000034 s, × 1.0472, 83 µs/rev netbeans x000_revs_xx00_added_0_copies eac3045b4fdd 51d4ae7f1290 : 1421 revs, 0.010019 s, 0.010443 s, +0.000424 s, × 1.0423, 7 µs/rev netbeans x000_revs_x000_added_x_copies e2063d266acd 6081d72689dc : 1533 revs, 0.015602 s, 0.015697 s, +0.000095 s, × 1.0061, 10 µs/rev netbeans x000_revs_x000_added_x000_copies ff453e9fee32 411350406ec2 : 5750 revs, 0.058759 s, 0.063528 s, +0.004769 s, × 1.0812, 11 µs/rev netbeans x0000_revs_xx000_added_x000_copies 588c2d1ced70 1aad62e59ddd : 66949 revs, 0.491550 s, 0.545515 s, +0.053965 s, × 1.1098, 8 µs/rev mozilla-central x_revs_x_added_0_copies 3697f962bb7b 7015fcdd43a2 : 2 revs, 0.000087 s, 0.000089 s, +0.000002 s, × 1.0230, 44 µs/rev mozilla-central x_revs_x000_added_0_copies dd390860c6c9 40d0c5bed75d : 8 revs, 0.000268 s, 0.000265 s, -0.000003 s, × 0.9888, 33 µs/rev mozilla-central x_revs_x_added_x_copies 8d198483ae3b 14207ffc2b2f : 9 revs, 0.000181 s, 0.000381 s, +0.000200 s, × 2.1050, 42 µs/rev mozilla-central x_revs_x00_added_x_copies 98cbc58cc6bc 446a150332c3 : 7 revs, 0.000661 s, 0.000672 s, +0.000011 s, × 1.0166, 96 µs/rev mozilla-central x_revs_x000_added_x000_copies 3c684b4b8f68 0a5e72d1b479 : 3 revs, 0.003256 s, 0.003497 s, +0.000241 s, × 1.0740, 1165 µs/rev mozilla-central x_revs_x0000_added_x0000_copies effb563bb7e5 c07a39dc4e80 : 6 revs, 0.066749 s, 0.073204 s, +0.006455 s, × 1.0967, 12200 µs/rev mozilla-central x000_revs_xx00_added_0_copies 6100d773079a 04a55431795e : 1593 revs, 0.006462 s, 0.006482 s, +0.000020 s, × 1.0031, 4 µs/rev mozilla-central x000_revs_x000_added_x_copies 9f17a6fc04f9 2d37b966abed : 41 revs, 0.004919 s, 0.005066 s, +0.000147 s, × 1.0299, 123 µs/rev mozilla-central x000_revs_x000_added_x000_copies 7c97034feb78 4407bd0c6330 : 7839 revs, 0.062421 s, 0.065707 s, +0.003286 s, × 1.0526, 8 µs/rev mozilla-central x0000_revs_xx000_added_0_copies 9eec5917337d 67118cc6dcad : 615 revs, 0.026633 s, 0.026800 s, +0.000167 s, × 1.0063, 43 µs/rev mozilla-central x0000_revs_xx000_added_x000_copies f78c615a656c 96a38b690156 : 30263 revs, 0.197792 s, 0.203856 s, +0.006064 s, × 1.0307, 6 µs/rev mozilla-central x00000_revs_x0000_added_x0000_copies 6832ae71433c 4c222a1d9a00 : 153721 revs, 1.259970 s, 1.293394 s, +0.033424 s, × 1.0265, 8 µs/rev mozilla-central x00000_revs_x00000_added_x000_copies 76caed42cf7c 1daa622bbe42 : 204976 revs, 1.689184 s, 1.698239 s, +0.009055 s, × 1.0054, 8 µs/rev mozilla-try x_revs_x_added_0_copies aaf6dde0deb8 9790f499805a : 2 revs, 0.000865 s, 0.000875 s, +0.000010 s, × 1.0116, 437 µs/rev mozilla-try x_revs_x000_added_0_copies d8d0222927b4 5bb8ce8c7450 : 2 revs, 0.000893 s, 0.000891 s, -0.000002 s, × 0.9978, 445 µs/rev mozilla-try x_revs_x_added_x_copies 092fcca11bdb 936255a0384a : 4 revs, 0.000172 s, 0.000292 s, +0.000120 s, × 1.6977, 73 µs/rev mozilla-try x_revs_x00_added_x_copies b53d2fadbdb5 017afae788ec : 2 revs, 0.001159 s, 0.003939 s, +0.002780 s, × 3.3986, 1969 µs/rev mozilla-try x_revs_x000_added_x000_copies 20408ad61ce5 6f0ee96e21ad : 1 revs, 0.031621 s, 0.033027 s, +0.001406 s, × 1.0445, 33027 µs/rev mozilla-try x_revs_x0000_added_x0000_copies effb563bb7e5 c07a39dc4e80 : 6 revs, 0.068571 s, 0.073703 s, +0.005132 s, × 1.0748, 12283 µs/rev mozilla-try x000_revs_xx00_added_0_copies 6100d773079a 04a55431795e : 1593 revs, 0.006452 s, 0.006469 s, +0.000017 s, × 1.0026, 4 µs/rev mozilla-try x000_revs_x000_added_x_copies 9f17a6fc04f9 2d37b966abed : 41 revs, 0.005443 s, 0.005278 s, -0.000165 s, × 0.9697, 128 µs/rev mozilla-try x000_revs_x000_added_x000_copies 1346fd0130e4 4c65cbdabc1f : 6657 revs, 0.063180 s, 0.064995 s, +0.001815 s, × 1.0287, 9 µs/rev mozilla-try x0000_revs_x_added_0_copies 63519bfd42ee a36a2a865d92 : 40314 revs, 0.293564 s, 0.301041 s, +0.007477 s, × 1.0255, 7 µs/rev mozilla-try x0000_revs_x_added_x_copies 9fe69ff0762d bcabf2a78927 : 38690 revs, 0.286595 s, 0.285575 s, -0.001020 s, × 0.9964, 7 µs/rev mozilla-try x0000_revs_xx000_added_x_copies 156f6e2674f2 4d0f2c178e66 : 8598 revs, 0.083256 s, 0.085597 s, +0.002341 s, × 1.0281, 9 µs/rev mozilla-try x0000_revs_xx000_added_0_copies 9eec5917337d 67118cc6dcad : 615 revs, 0.027282 s, 0.027118 s, -0.000164 s, × 0.9940, 44 µs/rev mozilla-try x0000_revs_xx000_added_x000_copies 89294cd501d9 7ccb2fc7ccb5 : 97052 revs, 1.343373 s, 2.119204 s, +0.775831 s, × 1.5775, 21 µs/rev mozilla-try x0000_revs_x0000_added_x0000_copies e928c65095ed e951f4ad123a : 52031 revs, 0.665737 s, 0.701479 s, +0.035742 s, × 1.0537, 13 µs/rev mozilla-try x00000_revs_x_added_0_copies 6a320851d377 1ebb79acd503 : 363753 revs, 5.138169 s, 4.482399 s, -0.655770 s, × 0.8724, 12 µs/rev mozilla-try x00000_revs_x00000_added_0_copies dc8a3ca7010e d16fde900c9c : 34414 revs, 0.573276 s, 0.574082 s, +0.000806 s, × 1.0014, 16 µs/rev mozilla-try x00000_revs_x_added_x_copies 5173c4b6f97c 95d83ee7242d : 362229 revs, 5.127809 s, 4.480366 s, -0.647443 s, × 0.8737, 12 µs/rev mozilla-try x00000_revs_x000_added_x_copies 9126823d0e9c ca82787bb23c : 359344 revs, 4.971136 s, 4.369070 s, -0.602066 s, × 0.8789, 12 µs/rev mozilla-try x00000_revs_x0000_added_x0000_copies 8d3fafa80d4b eb884023b810 : 192665 revs, 1.741678 s, 1.592506 s, -0.149172 s, × 0.9144, 8 µs/rev mozilla-try x00000_revs_x00000_added_x0000_copies 1b661134e2ca 1ae03d022d6d : 228985 revs, 40.314822 s, 87.824489 s, +47.509667 s, × 2.1785, 383 µs/rev mozilla-try x00000_revs_x00000_added_x000_copies 9b2a99adc05e 8e29777b48e6 : 382065 revs, 20.048029 s, 43.304637 s, +23.256608 s, × 2.1600, 113 µs/rev private : 459513 revs, 37.179470 s, 33.853687 s, -3.325783 s, × 0.9105, 73 µs/rev Differential Revision: https://phab.mercurial-scm.org/D9644
author Pierre-Yves David <pierre-yves.david@octobus.net>
date Tue, 15 Dec 2020 18:04:23 +0100
parents 590a840fa367
children d55b71393907
line wrap: on
line source

# sparse.py - functionality for sparse checkouts
#
# Copyright 2014 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import os

from .i18n import _
from .node import (
    hex,
    nullid,
)
from . import (
    error,
    match as matchmod,
    merge as mergemod,
    mergestate as mergestatemod,
    pathutil,
    pycompat,
    requirements,
    scmutil,
    util,
)
from .utils import hashutil


# Whether sparse features are enabled. This variable is intended to be
# temporary to facilitate porting sparse to core. It should eventually be
# a per-repo option, possibly a repo requirement.
enabled = False


def parseconfig(ui, raw, action):
    """Parse sparse config file content.

    action is the command which is trigerring this read, can be narrow, sparse

    Returns a tuple of includes, excludes, and profiles.
    """
    includes = set()
    excludes = set()
    profiles = set()
    current = None
    havesection = False

    for line in raw.split(b'\n'):
        line = line.strip()
        if not line or line.startswith(b'#'):
            # empty or comment line, skip
            continue
        elif line.startswith(b'%include '):
            line = line[9:].strip()
            if line:
                profiles.add(line)
        elif line == b'[include]':
            if havesection and current != includes:
                # TODO pass filename into this API so we can report it.
                raise error.Abort(
                    _(
                        b'%(action)s config cannot have includes '
                        b'after excludes'
                    )
                    % {b'action': action}
                )
            havesection = True
            current = includes
            continue
        elif line == b'[exclude]':
            havesection = True
            current = excludes
        elif line:
            if current is None:
                raise error.Abort(
                    _(
                        b'%(action)s config entry outside of '
                        b'section: %(line)s'
                    )
                    % {b'action': action, b'line': line},
                    hint=_(
                        b'add an [include] or [exclude] line '
                        b'to declare the entry type'
                    ),
                )

            if line.strip().startswith(b'/'):
                ui.warn(
                    _(
                        b'warning: %(action)s profile cannot use'
                        b' paths starting with /, ignoring %(line)s\n'
                    )
                    % {b'action': action, b'line': line}
                )
                continue
            current.add(line)

    return includes, excludes, profiles


# Exists as separate function to facilitate monkeypatching.
def readprofile(repo, profile, changeid):
    """Resolve the raw content of a sparse profile file."""
    # TODO add some kind of cache here because this incurs a manifest
    # resolve and can be slow.
    return repo.filectx(profile, changeid=changeid).data()


def patternsforrev(repo, rev):
    """Obtain sparse checkout patterns for the given rev.

    Returns a tuple of iterables representing includes, excludes, and
    patterns.
    """
    # Feature isn't enabled. No-op.
    if not enabled:
        return set(), set(), set()

    raw = repo.vfs.tryread(b'sparse')
    if not raw:
        return set(), set(), set()

    if rev is None:
        raise error.Abort(
            _(b'cannot parse sparse patterns from working directory')
        )

    includes, excludes, profiles = parseconfig(repo.ui, raw, b'sparse')
    ctx = repo[rev]

    if profiles:
        visited = set()
        while profiles:
            profile = profiles.pop()
            if profile in visited:
                continue

            visited.add(profile)

            try:
                raw = readprofile(repo, profile, rev)
            except error.ManifestLookupError:
                msg = (
                    b"warning: sparse profile '%s' not found "
                    b"in rev %s - ignoring it\n" % (profile, ctx)
                )
                # experimental config: sparse.missingwarning
                if repo.ui.configbool(b'sparse', b'missingwarning'):
                    repo.ui.warn(msg)
                else:
                    repo.ui.debug(msg)
                continue

            pincludes, pexcludes, subprofs = parseconfig(
                repo.ui, raw, b'sparse'
            )
            includes.update(pincludes)
            excludes.update(pexcludes)
            profiles.update(subprofs)

        profiles = visited

    if includes:
        includes.add(b'.hg*')

    return includes, excludes, profiles


def activeconfig(repo):
    """Determine the active sparse config rules.

    Rules are constructed by reading the current sparse config and bringing in
    referenced profiles from parents of the working directory.
    """
    revs = [
        repo.changelog.rev(node)
        for node in repo.dirstate.parents()
        if node != nullid
    ]

    allincludes = set()
    allexcludes = set()
    allprofiles = set()

    for rev in revs:
        includes, excludes, profiles = patternsforrev(repo, rev)
        allincludes |= includes
        allexcludes |= excludes
        allprofiles |= profiles

    return allincludes, allexcludes, allprofiles


def configsignature(repo, includetemp=True):
    """Obtain the signature string for the current sparse configuration.

    This is used to construct a cache key for matchers.
    """
    cache = repo._sparsesignaturecache

    signature = cache.get(b'signature')

    if includetemp:
        tempsignature = cache.get(b'tempsignature')
    else:
        tempsignature = b'0'

    if signature is None or (includetemp and tempsignature is None):
        signature = hex(hashutil.sha1(repo.vfs.tryread(b'sparse')).digest())
        cache[b'signature'] = signature

        if includetemp:
            raw = repo.vfs.tryread(b'tempsparse')
            tempsignature = hex(hashutil.sha1(raw).digest())
            cache[b'tempsignature'] = tempsignature

    return b'%s %s' % (signature, tempsignature)


def writeconfig(repo, includes, excludes, profiles):
    """Write the sparse config file given a sparse configuration."""
    with repo.vfs(b'sparse', b'wb') as fh:
        for p in sorted(profiles):
            fh.write(b'%%include %s\n' % p)

        if includes:
            fh.write(b'[include]\n')
            for i in sorted(includes):
                fh.write(i)
                fh.write(b'\n')

        if excludes:
            fh.write(b'[exclude]\n')
            for e in sorted(excludes):
                fh.write(e)
                fh.write(b'\n')

    repo._sparsesignaturecache.clear()


def readtemporaryincludes(repo):
    raw = repo.vfs.tryread(b'tempsparse')
    if not raw:
        return set()

    return set(raw.split(b'\n'))


def writetemporaryincludes(repo, includes):
    repo.vfs.write(b'tempsparse', b'\n'.join(sorted(includes)))
    repo._sparsesignaturecache.clear()


def addtemporaryincludes(repo, additional):
    includes = readtemporaryincludes(repo)
    for i in additional:
        includes.add(i)
    writetemporaryincludes(repo, includes)


def prunetemporaryincludes(repo):
    if not enabled or not repo.vfs.exists(b'tempsparse'):
        return

    s = repo.status()
    if s.modified or s.added or s.removed or s.deleted:
        # Still have pending changes. Don't bother trying to prune.
        return

    sparsematch = matcher(repo, includetemp=False)
    dirstate = repo.dirstate
    mresult = mergemod.mergeresult()
    dropped = []
    tempincludes = readtemporaryincludes(repo)
    for file in tempincludes:
        if file in dirstate and not sparsematch(file):
            message = _(b'dropping temporarily included sparse files')
            mresult.addfile(file, mergestatemod.ACTION_REMOVE, None, message)
            dropped.append(file)

    mergemod.applyupdates(
        repo, mresult, repo[None], repo[b'.'], False, wantfiledata=False
    )

    # Fix dirstate
    for file in dropped:
        dirstate.drop(file)

    repo.vfs.unlink(b'tempsparse')
    repo._sparsesignaturecache.clear()
    msg = _(
        b'cleaned up %d temporarily added file(s) from the '
        b'sparse checkout\n'
    )
    repo.ui.status(msg % len(tempincludes))


def forceincludematcher(matcher, includes):
    """Returns a matcher that returns true for any of the forced includes
    before testing against the actual matcher."""
    kindpats = [(b'path', include, b'') for include in includes]
    includematcher = matchmod.includematcher(b'', kindpats)
    return matchmod.unionmatcher([includematcher, matcher])


def matcher(repo, revs=None, includetemp=True):
    """Obtain a matcher for sparse working directories for the given revs.

    If multiple revisions are specified, the matcher is the union of all
    revs.

    ``includetemp`` indicates whether to use the temporary sparse profile.
    """
    # If sparse isn't enabled, sparse matcher matches everything.
    if not enabled:
        return matchmod.always()

    if not revs or revs == [None]:
        revs = [
            repo.changelog.rev(node)
            for node in repo.dirstate.parents()
            if node != nullid
        ]

    signature = configsignature(repo, includetemp=includetemp)

    key = b'%s %s' % (signature, b' '.join(map(pycompat.bytestr, revs)))

    result = repo._sparsematchercache.get(key)
    if result:
        return result

    matchers = []
    for rev in revs:
        try:
            includes, excludes, profiles = patternsforrev(repo, rev)

            if includes or excludes:
                matcher = matchmod.match(
                    repo.root,
                    b'',
                    [],
                    include=includes,
                    exclude=excludes,
                    default=b'relpath',
                )
                matchers.append(matcher)
        except IOError:
            pass

    if not matchers:
        result = matchmod.always()
    elif len(matchers) == 1:
        result = matchers[0]
    else:
        result = matchmod.unionmatcher(matchers)

    if includetemp:
        tempincludes = readtemporaryincludes(repo)
        result = forceincludematcher(result, tempincludes)

    repo._sparsematchercache[key] = result

    return result


def filterupdatesactions(repo, wctx, mctx, branchmerge, mresult):
    """Filter updates to only lay out files that match the sparse rules."""
    if not enabled:
        return

    oldrevs = [pctx.rev() for pctx in wctx.parents()]
    oldsparsematch = matcher(repo, oldrevs)

    if oldsparsematch.always():
        return

    files = set()
    prunedactions = {}

    if branchmerge:
        # If we're merging, use the wctx filter, since we're merging into
        # the wctx.
        sparsematch = matcher(repo, [wctx.p1().rev()])
    else:
        # If we're updating, use the target context's filter, since we're
        # moving to the target context.
        sparsematch = matcher(repo, [mctx.rev()])

    temporaryfiles = []
    for file, action in mresult.filemap():
        type, args, msg = action
        files.add(file)
        if sparsematch(file):
            prunedactions[file] = action
        elif type == mergestatemod.ACTION_MERGE:
            temporaryfiles.append(file)
            prunedactions[file] = action
        elif branchmerge:
            if type not in mergestatemod.NO_OP_ACTIONS:
                temporaryfiles.append(file)
                prunedactions[file] = action
        elif type == mergestatemod.ACTION_FORGET:
            prunedactions[file] = action
        elif file in wctx:
            prunedactions[file] = (mergestatemod.ACTION_REMOVE, args, msg)

        # in case or rename on one side, it is possible that f1 might not
        # be present in sparse checkout we should include it
        # TODO: should we do the same for f2?
        # exists as a separate check because file can be in sparse and hence
        # if we try to club this condition in above `elif type == ACTION_MERGE`
        # it won't be triggered
        if branchmerge and type == mergestatemod.ACTION_MERGE:
            f1, f2, fa, move, anc = args
            if not sparsematch(f1):
                temporaryfiles.append(f1)

    if len(temporaryfiles) > 0:
        repo.ui.status(
            _(
                b'temporarily included %d file(s) in the sparse '
                b'checkout for merging\n'
            )
            % len(temporaryfiles)
        )
        addtemporaryincludes(repo, temporaryfiles)

        # Add the new files to the working copy so they can be merged, etc
        tmresult = mergemod.mergeresult()
        message = b'temporarily adding to sparse checkout'
        wctxmanifest = repo[None].manifest()
        for file in temporaryfiles:
            if file in wctxmanifest:
                fctx = repo[None][file]
                tmresult.addfile(
                    file,
                    mergestatemod.ACTION_GET,
                    (fctx.flags(), False),
                    message,
                )

        mergemod.applyupdates(
            repo, tmresult, repo[None], repo[b'.'], False, wantfiledata=False
        )

        dirstate = repo.dirstate
        for file, flags, msg in tmresult.getactions([mergestatemod.ACTION_GET]):
            dirstate.normal(file)

    profiles = activeconfig(repo)[2]
    changedprofiles = profiles & files
    # If an active profile changed during the update, refresh the checkout.
    # Don't do this during a branch merge, since all incoming changes should
    # have been handled by the temporary includes above.
    if changedprofiles and not branchmerge:
        mf = mctx.manifest()
        for file in mf:
            old = oldsparsematch(file)
            new = sparsematch(file)
            if not old and new:
                flags = mf.flags(file)
                prunedactions[file] = (
                    mergestatemod.ACTION_GET,
                    (flags, False),
                    b'',
                )
            elif old and not new:
                prunedactions[file] = (mergestatemod.ACTION_REMOVE, [], b'')

    mresult.setactions(prunedactions)


def refreshwdir(repo, origstatus, origsparsematch, force=False):
    """Refreshes working directory by taking sparse config into account.

    The old status and sparse matcher is compared against the current sparse
    matcher.

    Will abort if a file with pending changes is being excluded or included
    unless ``force`` is True.
    """
    # Verify there are no pending changes
    pending = set()
    pending.update(origstatus.modified)
    pending.update(origstatus.added)
    pending.update(origstatus.removed)
    sparsematch = matcher(repo)
    abort = False

    for f in pending:
        if not sparsematch(f):
            repo.ui.warn(_(b"pending changes to '%s'\n") % f)
            abort = not force

    if abort:
        raise error.Abort(
            _(b'could not update sparseness due to pending changes')
        )

    # Calculate merge result
    dirstate = repo.dirstate
    ctx = repo[b'.']
    added = []
    lookup = []
    dropped = []
    mf = ctx.manifest()
    files = set(mf)
    mresult = mergemod.mergeresult()

    for file in files:
        old = origsparsematch(file)
        new = sparsematch(file)
        # Add files that are newly included, or that don't exist in
        # the dirstate yet.
        if (new and not old) or (old and new and not file in dirstate):
            fl = mf.flags(file)
            if repo.wvfs.exists(file):
                mresult.addfile(file, mergestatemod.ACTION_EXEC, (fl,), b'')
                lookup.append(file)
            else:
                mresult.addfile(
                    file, mergestatemod.ACTION_GET, (fl, False), b''
                )
                added.append(file)
        # Drop files that are newly excluded, or that still exist in
        # the dirstate.
        elif (old and not new) or (not old and not new and file in dirstate):
            dropped.append(file)
            if file not in pending:
                mresult.addfile(file, mergestatemod.ACTION_REMOVE, [], b'')

    # Verify there are no pending changes in newly included files
    abort = False
    for file in lookup:
        repo.ui.warn(_(b"pending changes to '%s'\n") % file)
        abort = not force
    if abort:
        raise error.Abort(
            _(
                b'cannot change sparseness due to pending '
                b'changes (delete the files or use '
                b'--force to bring them back dirty)'
            )
        )

    # Check for files that were only in the dirstate.
    for file, state in pycompat.iteritems(dirstate):
        if not file in files:
            old = origsparsematch(file)
            new = sparsematch(file)
            if old and not new:
                dropped.append(file)

    mergemod.applyupdates(
        repo, mresult, repo[None], repo[b'.'], False, wantfiledata=False
    )

    # Fix dirstate
    for file in added:
        dirstate.normal(file)

    for file in dropped:
        dirstate.drop(file)

    for file in lookup:
        # File exists on disk, and we're bringing it back in an unknown state.
        dirstate.normallookup(file)

    return added, dropped, lookup


def aftercommit(repo, node):
    """Perform actions after a working directory commit."""
    # This function is called unconditionally, even if sparse isn't
    # enabled.
    ctx = repo[node]

    profiles = patternsforrev(repo, ctx.rev())[2]

    # profiles will only have data if sparse is enabled.
    if profiles & set(ctx.files()):
        origstatus = repo.status()
        origsparsematch = matcher(repo)
        refreshwdir(repo, origstatus, origsparsematch, force=True)

    prunetemporaryincludes(repo)


def _updateconfigandrefreshwdir(
    repo, includes, excludes, profiles, force=False, removing=False
):
    """Update the sparse config and working directory state."""
    raw = repo.vfs.tryread(b'sparse')
    oldincludes, oldexcludes, oldprofiles = parseconfig(repo.ui, raw, b'sparse')

    oldstatus = repo.status()
    oldmatch = matcher(repo)
    oldrequires = set(repo.requirements)

    # TODO remove this try..except once the matcher integrates better
    # with dirstate. We currently have to write the updated config
    # because that will invalidate the matcher cache and force a
    # re-read. We ideally want to update the cached matcher on the
    # repo instance then flush the new config to disk once wdir is
    # updated. But this requires massive rework to matcher() and its
    # consumers.

    if requirements.SPARSE_REQUIREMENT in oldrequires and removing:
        repo.requirements.discard(requirements.SPARSE_REQUIREMENT)
        scmutil.writereporequirements(repo)
    elif requirements.SPARSE_REQUIREMENT not in oldrequires:
        repo.requirements.add(requirements.SPARSE_REQUIREMENT)
        scmutil.writereporequirements(repo)

    try:
        writeconfig(repo, includes, excludes, profiles)
        return refreshwdir(repo, oldstatus, oldmatch, force=force)
    except Exception:
        if repo.requirements != oldrequires:
            repo.requirements.clear()
            repo.requirements |= oldrequires
            scmutil.writereporequirements(repo)
        writeconfig(repo, oldincludes, oldexcludes, oldprofiles)
        raise


def clearrules(repo, force=False):
    """Clears include/exclude rules from the sparse config.

    The remaining sparse config only has profiles, if defined. The working
    directory is refreshed, as needed.
    """
    with repo.wlock():
        raw = repo.vfs.tryread(b'sparse')
        includes, excludes, profiles = parseconfig(repo.ui, raw, b'sparse')

        if not includes and not excludes:
            return

        _updateconfigandrefreshwdir(repo, set(), set(), profiles, force=force)


def importfromfiles(repo, opts, paths, force=False):
    """Import sparse config rules from files.

    The updated sparse config is written out and the working directory
    is refreshed, as needed.
    """
    with repo.wlock():
        # read current configuration
        raw = repo.vfs.tryread(b'sparse')
        includes, excludes, profiles = parseconfig(repo.ui, raw, b'sparse')
        aincludes, aexcludes, aprofiles = activeconfig(repo)

        # Import rules on top; only take in rules that are not yet
        # part of the active rules.
        changed = False
        for p in paths:
            with util.posixfile(util.expandpath(p), mode=b'rb') as fh:
                raw = fh.read()

            iincludes, iexcludes, iprofiles = parseconfig(
                repo.ui, raw, b'sparse'
            )
            oldsize = len(includes) + len(excludes) + len(profiles)
            includes.update(iincludes - aincludes)
            excludes.update(iexcludes - aexcludes)
            profiles.update(iprofiles - aprofiles)
            if len(includes) + len(excludes) + len(profiles) > oldsize:
                changed = True

        profilecount = includecount = excludecount = 0
        fcounts = (0, 0, 0)

        if changed:
            profilecount = len(profiles - aprofiles)
            includecount = len(includes - aincludes)
            excludecount = len(excludes - aexcludes)

            fcounts = map(
                len,
                _updateconfigandrefreshwdir(
                    repo, includes, excludes, profiles, force=force
                ),
            )

        printchanges(
            repo.ui, opts, profilecount, includecount, excludecount, *fcounts
        )


def updateconfig(
    repo,
    pats,
    opts,
    include=False,
    exclude=False,
    reset=False,
    delete=False,
    enableprofile=False,
    disableprofile=False,
    force=False,
    usereporootpaths=False,
):
    """Perform a sparse config update.

    Only one of the actions may be performed.

    The new config is written out and a working directory refresh is performed.
    """
    with repo.wlock():
        raw = repo.vfs.tryread(b'sparse')
        oldinclude, oldexclude, oldprofiles = parseconfig(
            repo.ui, raw, b'sparse'
        )

        if reset:
            newinclude = set()
            newexclude = set()
            newprofiles = set()
        else:
            newinclude = set(oldinclude)
            newexclude = set(oldexclude)
            newprofiles = set(oldprofiles)

        if any(os.path.isabs(pat) for pat in pats):
            raise error.Abort(_(b'paths cannot be absolute'))

        if not usereporootpaths:
            # let's treat paths as relative to cwd
            root, cwd = repo.root, repo.getcwd()
            abspats = []
            for kindpat in pats:
                kind, pat = matchmod._patsplit(kindpat, None)
                if kind in matchmod.cwdrelativepatternkinds or kind is None:
                    ap = (kind + b':' if kind else b'') + pathutil.canonpath(
                        root, cwd, pat
                    )
                    abspats.append(ap)
                else:
                    abspats.append(kindpat)
            pats = abspats

        if include:
            newinclude.update(pats)
        elif exclude:
            newexclude.update(pats)
        elif enableprofile:
            newprofiles.update(pats)
        elif disableprofile:
            newprofiles.difference_update(pats)
        elif delete:
            newinclude.difference_update(pats)
            newexclude.difference_update(pats)

        profilecount = len(newprofiles - oldprofiles) - len(
            oldprofiles - newprofiles
        )
        includecount = len(newinclude - oldinclude) - len(
            oldinclude - newinclude
        )
        excludecount = len(newexclude - oldexclude) - len(
            oldexclude - newexclude
        )

        fcounts = map(
            len,
            _updateconfigandrefreshwdir(
                repo,
                newinclude,
                newexclude,
                newprofiles,
                force=force,
                removing=reset,
            ),
        )

        printchanges(
            repo.ui, opts, profilecount, includecount, excludecount, *fcounts
        )


def printchanges(
    ui,
    opts,
    profilecount=0,
    includecount=0,
    excludecount=0,
    added=0,
    dropped=0,
    conflicting=0,
):
    """Print output summarizing sparse config changes."""
    with ui.formatter(b'sparse', opts) as fm:
        fm.startitem()
        fm.condwrite(
            ui.verbose,
            b'profiles_added',
            _(b'Profiles changed: %d\n'),
            profilecount,
        )
        fm.condwrite(
            ui.verbose,
            b'include_rules_added',
            _(b'Include rules changed: %d\n'),
            includecount,
        )
        fm.condwrite(
            ui.verbose,
            b'exclude_rules_added',
            _(b'Exclude rules changed: %d\n'),
            excludecount,
        )

        # In 'plain' verbose mode, mergemod.applyupdates already outputs what
        # files are added or removed outside of the templating formatter
        # framework. No point in repeating ourselves in that case.
        if not fm.isplain():
            fm.condwrite(
                ui.verbose, b'files_added', _(b'Files added: %d\n'), added
            )
            fm.condwrite(
                ui.verbose, b'files_dropped', _(b'Files dropped: %d\n'), dropped
            )
            fm.condwrite(
                ui.verbose,
                b'files_conflicting',
                _(b'Files conflicting: %d\n'),
                conflicting,
            )