annotate mercurial/sparse.py @ 33323:252500520d60

sparse: refactor update actions filtering and call from core

merge.calculateupdates() now filters the update actions through sparse
by default.

The filtering no-ops if sparse isn't enabled or no sparse config
is defined.

The function has been refactored to behave more like a filter
instead of a wrapper of merge.calculateupdates().

We should arguably take sparse into account earlier in
merge.calculateupdates(). This patch preserves the old behavior
of applying sparse at the end of update calculation, which is the
simplest and safest approach.

# 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 collections
import hashlib
import os

from .i18n import _
from .node import nullid
from . import (
    error,
    match as matchmod,
    merge as mergemod,
    pycompat,
)

# 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):
    """Parse sparse config file content.

    Returns a tuple of includes, excludes, and profiles.
    """
    includes = set()
    excludes = set()
    current = includes
    profiles = []
    for line in raw.split('\n'):
        line = line.strip()
        if not line or line.startswith('#'):
            # empty or comment line, skip
            continue
        elif line.startswith('%include '):
            line = line[9:].strip()
            if line:
                profiles.append(line)
        elif line == '[include]':
            if current != includes:
                # TODO pass filename into this API so we can report it.
                raise error.Abort(_('sparse config cannot have includes ' +
                                    'after excludes'))
            continue
        elif line == '[exclude]':
            current = excludes
        elif line:
            if line.strip().startswith('/'):
                ui.warn(_('warning: sparse profile cannot use' +
                          ' paths starting with /, ignoring %s\n') % 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(), []

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

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

    includes, excludes, profiles = parseconfig(repo.ui, raw)
    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 = (
                    "warning: sparse profile '%s' not found "
                    "in rev %s - ignoring it\n" % (profile, ctx))
                # experimental config: sparse.missingwarning
                if repo.ui.configbool(
                        'sparse', 'missingwarning', True):
                    repo.ui.warn(msg)
                else:
                    repo.ui.debug(msg)
                continue

            pincludes, pexcludes, subprofs = parseconfig(repo.ui, raw)
            includes.update(pincludes)
            excludes.update(pexcludes)
            for subprofile in subprofs:
                profiles.append(subprofile)

        profiles = visited

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

    return includes, excludes, profiles

def activeprofiles(repo):
    revs = [repo.changelog.rev(node) for node in
            repo.dirstate.parents() if node != nullid]

    profiles = set()
    for rev in revs:
        profiles.update(patternsforrev(repo, rev)[2])

    return profiles

def invalidatesignaturecache(repo):
    repo._sparsesignaturecache.clear()

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('signature')

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

    if signature is None or (includetemp and tempsignature is None):
        signature = hashlib.sha1(repo.vfs.tryread('sparse')).hexdigest()
        cache['signature'] = signature

        if includetemp:
            raw = repo.vfs.tryread('tempsparse')
            tempsignature = hashlib.sha1(raw).hexdigest()
            cache['tempsignature'] = tempsignature

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

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

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

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

    invalidatesignaturecache(repo)

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

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

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

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('tempsparse'):
        return

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

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

    typeactions = collections.defaultdict(list)
    typeactions['r'] = actions
    mergemod.applyupdates(repo, typeactions, repo[None], repo['.'], False)

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

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

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(repo.root, '')

    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 = '%s %s' % (signature, ' '.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:
                # Explicitly include subdirectories of includes so
                # status will walk them down to the actual include.
                subdirs = set()
                for include in includes:
                    # TODO consider using posix path functions here so Windows
                    # \ directory separators don't come into play.
                    dirname = os.path.dirname(include)
                    # basename is used to avoid issues with absolute
                    # paths (which on Windows can include the drive).
                    while os.path.basename(dirname):
                        subdirs.add(dirname)
                        dirname = os.path.dirname(dirname)

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

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

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

    repo._sparsematchercache[key] = result

    return result

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

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

    if oldsparsematch.always():
        return actions

    files = set()
    prunedactions = {}

    if branchmerge:
        # If we're merging, use the wctx filter, since we're merging into
        # the wctx.
        sparsematch = matcher(repo, [wctx.parents()[0].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 actions.iteritems():
        type, args, msg = action
        files.add(file)
        if sparsematch(file):
            prunedactions[file] = action
        elif type == 'm':
            temporaryfiles.append(file)
            prunedactions[file] = action
        elif branchmerge:
            if type != 'k':
                temporaryfiles.append(file)
                prunedactions[file] = action
        elif type == 'f':
            prunedactions[file] = action
        elif file in wctx:
            prunedactions[file] = ('r', args, msg)

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

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

        typeactions = collections.defaultdict(list)
        typeactions['g'] = actions
        mergemod.applyupdates(repo, typeactions, repo[None], repo['.'],
                              False)

        dirstate = repo.dirstate
        for file, flags, msg in actions:
            dirstate.normal(file)

    profiles = activeprofiles(repo)
    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] = ('g', (flags, False), '')
            elif old and not new:
                prunedactions[file] = ('r', [], '')

    return prunedactions