view mercurial/templatekw.py @ 24735:07200e3332a1

tags: extract .hgtags filenodes cache to a standalone file

Resolution of .hgtags filenodes values has historically been a
performance pain point for large repositories, where reading individual
manifests can take over 100ms. Multiplied by hundreds or even thousands
of heads and resolving .hgtags filenodes becomes a performance issue.

This patch establishes a standalone cache file holding the .hgtags
filenodes for each changeset. After this patch, the .hgtags filenode
for any particular changeset should only have to be computed once
during the lifetime of the repository.

The introduced hgtagsfnodes1 cache file is modeled after the rev branch
cache: the cache is effectively an array of entries consisting of a
changeset fragment and the filenode for a revision. The file grows in
proportion to the length of the repository (24 bytes per changeset) and
is truncated when the repository is stripped. The file is not written
unless tag info is requested and tags have changed since last time.

This patch partially addresses issue4550. Future patches will split the
"tags" cache file into per-filter files and will refactor the cache
format to not capture the .hgtags fnodes, as these are now stored in
the hgtagsfnodes1 cache. This patch is capable of standing alone. We
should not have to wait on the tags cache filter split and format
refactor for this patch to land.

# templatekw.py - common changeset template keywords
#
# Copyright 2005-2009 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from node import hex
import patch, util, error
import hbisect

# This helper class allows us to handle both:
#  "{files}" (legacy command-line-specific list hack) and
#  "{files % '{file}\n'}" (hgweb-style with inlining and function support)
# and to access raw values:
#  "{ifcontains(file, files, ...)}", "{ifcontains(key, extras, ...)}"
#  "{get(extras, key)}"

class _hybrid(object):
    def __init__(self, gen, values, makemap, joinfmt=None):
        self.gen = gen
        self.values = values
        self._makemap = makemap
        if joinfmt:
            self.joinfmt = joinfmt
        else:
            self.joinfmt = lambda x: x.values()[0]
    def __iter__(self):
        return self.gen
    def __call__(self):
        makemap = self._makemap
        for x in self.values:
            yield makemap(x)
    def __contains__(self, x):
        return x in self.values
    def __len__(self):
        return len(self.values)
    def __getattr__(self, name):
        if name != 'get':
            raise AttributeError(name)
        return getattr(self.values, name)

def showlist(name, values, plural=None, element=None, **args):
    if not element:
        element = name
    f = _showlist(name, values, plural, **args)
    return _hybrid(f, values, lambda x: {element: x})

def _showlist(name, values, plural=None, **args):
    '''expand set of values.
    name is name of key in template map.
    values is list of strings or dicts.
    plural is plural of name, if not simply name + 's'.

    expansion works like this, given name 'foo'.

    if values is empty, expand 'no_foos'.

    if 'foo' not in template map, return values as a string,
    joined by space.

    expand 'start_foos'.

    for each value, expand 'foo'. if 'last_foo' in template
    map, expand it instead of 'foo' for last key.

    expand 'end_foos'.
    '''
    templ = args['templ']
    if plural:
        names = plural
    else: names = name + 's'
    if not values:
        noname = 'no_' + names
        if noname in templ:
            yield templ(noname, **args)
        return
    if name not in templ:
        if isinstance(values[0], str):
            yield ' '.join(values)
        else:
            for v in values:
                yield dict(v, **args)
        return
    startname = 'start_' + names
    if startname in templ:
        yield templ(startname, **args)
    vargs = args.copy()
    def one(v, tag=name):
        try:
            vargs.update(v)
        except (AttributeError, ValueError):
            try:
                for a, b in v:
                    vargs[a] = b
            except ValueError:
                vargs[name] = v
        return templ(tag, **vargs)
    lastname = 'last_' + name
    if lastname in templ:
        last = values.pop()
    else:
        last = None
    for v in values:
        yield one(v)
    if last is not None:
        yield one(last, tag=lastname)
    endname = 'end_' + names
    if endname in templ:
        yield templ(endname, **args)

def getfiles(repo, ctx, revcache):
    if 'files' not in revcache:
        revcache['files'] = repo.status(ctx.p1().node(), ctx.node())[:3]
    return revcache['files']

def getlatesttags(repo, ctx, cache):
    '''return date, distance and name for the latest tag of rev'''

    if 'latesttags' not in cache:
        # Cache mapping from rev to a tuple with tag date, tag
        # distance and tag name
        cache['latesttags'] = {-1: (0, 0, 'null')}
    latesttags = cache['latesttags']

    rev = ctx.rev()
    todo = [rev]
    while todo:
        rev = todo.pop()
        if rev in latesttags:
            continue
        ctx = repo[rev]
        tags = [t for t in ctx.tags()
                if (repo.tagtype(t) and repo.tagtype(t) != 'local')]
        if tags:
            latesttags[rev] = ctx.date()[0], 0, ':'.join(sorted(tags))
            continue
        try:
            # The tuples are laid out so the right one can be found by
            # comparison.
            pdate, pdist, ptag = max(
                latesttags[p.rev()] for p in ctx.parents())
        except KeyError:
            # Cache miss - recurse
            todo.append(rev)
            todo.extend(p.rev() for p in ctx.parents())
            continue
        latesttags[rev] = pdate, pdist + 1, ptag
    return latesttags[rev]

def getrenamedfn(repo, endrev=None):
    rcache = {}
    if endrev is None:
        endrev = len(repo)

    def getrenamed(fn, rev):
        '''looks up all renames for a file (up to endrev) the first
        time the file is given. It indexes on the changerev and only
        parses the manifest if linkrev != changerev.
        Returns rename info for fn at changerev rev.'''
        if fn not in rcache:
            rcache[fn] = {}
            fl = repo.file(fn)
            for i in fl:
                lr = fl.linkrev(i)
                renamed = fl.renamed(fl.node(i))
                rcache[fn][lr] = renamed
                if lr >= endrev:
                    break
        if rev in rcache[fn]:
            return rcache[fn][rev]

        # If linkrev != rev (i.e. rev not found in rcache) fallback to
        # filectx logic.
        try:
            return repo[rev][fn].renamed()
        except error.LookupError:
            return None

    return getrenamed


def showauthor(repo, ctx, templ, **args):
    """:author: String. The unmodified author of the changeset."""
    return ctx.user()

def showbisect(repo, ctx, templ, **args):
    """:bisect: String. The changeset bisection status."""
    return hbisect.label(repo, ctx.node())

def showbranch(**args):
    """:branch: String. The name of the branch on which the changeset was
    committed.
    """
    return args['ctx'].branch()

def showbranches(**args):
    """:branches: List of strings. The name of the branch on which the
    changeset was committed. Will be empty if the branch name was
    default.
    """
    branch = args['ctx'].branch()
    if branch != 'default':
        return showlist('branch', [branch], plural='branches', **args)
    return showlist('branch', [], plural='branches', **args)

def showbookmarks(**args):
    """:bookmarks: List of strings. Any bookmarks associated with the
    changeset.
    """
    repo = args['ctx']._repo
    bookmarks = args['ctx'].bookmarks()
    current = repo._bookmarkcurrent
    makemap = lambda v: {'bookmark': v, 'current': current}
    f = _showlist('bookmark', bookmarks, **args)
    return _hybrid(f, bookmarks, makemap, lambda x: x['bookmark'])

def showchildren(**args):
    """:children: List of strings. The children of the changeset."""
    ctx = args['ctx']
    childrevs = ['%d:%s' % (cctx, cctx) for cctx in ctx.children()]
    return showlist('children', childrevs, element='child', **args)

def showcurrentbookmark(**args):
    """:currentbookmark: String. The active bookmark, if it is
    associated with the changeset"""
    import bookmarks as bookmarks # to avoid circular import issues
    repo = args['repo']
    if bookmarks.iscurrent(repo):
        current = repo._bookmarkcurrent
        if current in args['ctx'].bookmarks():
            return current
    return ''

def showdate(repo, ctx, templ, **args):
    """:date: Date information. The date when the changeset was committed."""
    return ctx.date()

def showdescription(repo, ctx, templ, **args):
    """:desc: String. The text of the changeset description."""
    return ctx.description().strip()

def showdiffstat(repo, ctx, templ, **args):
    """:diffstat: String. Statistics of changes with the following format:
    "modified files: +added/-removed lines"
    """
    stats = patch.diffstatdata(util.iterlines(ctx.diff()))
    maxname, maxtotal, adds, removes, binary = patch.diffstatsum(stats)
    return '%s: +%s/-%s' % (len(stats), adds, removes)

def showextras(**args):
    """:extras: List of dicts with key, value entries of the 'extras'
    field of this changeset."""
    extras = args['ctx'].extra()
    extras = util.sortdict((k, extras[k]) for k in sorted(extras))
    makemap = lambda k: {'key': k, 'value': extras[k]}
    c = [makemap(k) for k in extras]
    f = _showlist('extra', c, plural='extras', **args)
    return _hybrid(f, extras, makemap,
                   lambda x: '%s=%s' % (x['key'], x['value']))

def showfileadds(**args):
    """:file_adds: List of strings. Files added by this changeset."""
    repo, ctx, revcache = args['repo'], args['ctx'], args['revcache']
    return showlist('file_add', getfiles(repo, ctx, revcache)[1],
                    element='file', **args)

def showfilecopies(**args):
    """:file_copies: List of strings. Files copied in this changeset with
    their sources.
    """
    cache, ctx = args['cache'], args['ctx']
    copies = args['revcache'].get('copies')
    if copies is None:
        if 'getrenamed' not in cache:
            cache['getrenamed'] = getrenamedfn(args['repo'])
        copies = []
        getrenamed = cache['getrenamed']
        for fn in ctx.files():
            rename = getrenamed(fn, ctx.rev())
            if rename:
                copies.append((fn, rename[0]))

    copies = util.sortdict(copies)
    makemap = lambda k: {'name': k, 'source': copies[k]}
    c = [makemap(k) for k in copies]
    f = _showlist('file_copy', c, plural='file_copies', **args)
    return _hybrid(f, copies, makemap,
                   lambda x: '%s (%s)' % (x['name'], x['source']))

# showfilecopiesswitch() displays file copies only if copy records are
# provided before calling the templater, usually with a --copies
# command line switch.
def showfilecopiesswitch(**args):
    """:file_copies_switch: List of strings. Like "file_copies" but displayed
    only if the --copied switch is set.
    """
    copies = args['revcache'].get('copies') or []
    copies = util.sortdict(copies)
    makemap = lambda k: {'name': k, 'source': copies[k]}
    c = [makemap(k) for k in copies]
    f = _showlist('file_copy', c, plural='file_copies', **args)
    return _hybrid(f, copies, makemap,
                   lambda x: '%s (%s)' % (x['name'], x['source']))

def showfiledels(**args):
    """:file_dels: List of strings. Files removed by this changeset."""
    repo, ctx, revcache = args['repo'], args['ctx'], args['revcache']
    return showlist('file_del', getfiles(repo, ctx, revcache)[2],
                    element='file', **args)

def showfilemods(**args):
    """:file_mods: List of strings. Files modified by this changeset."""
    repo, ctx, revcache = args['repo'], args['ctx'], args['revcache']
    return showlist('file_mod', getfiles(repo, ctx, revcache)[0],
                    element='file', **args)

def showfiles(**args):
    """:files: List of strings. All files modified, added, or removed by this
    changeset.
    """
    return showlist('file', args['ctx'].files(), **args)

def showlatesttag(repo, ctx, templ, cache, **args):
    """:latesttag: String. Most recent global tag in the ancestors of this
    changeset.
    """
    return getlatesttags(repo, ctx, cache)[2]

def showlatesttagdistance(repo, ctx, templ, cache, **args):
    """:latesttagdistance: Integer. Longest path to the latest tag."""
    return getlatesttags(repo, ctx, cache)[1]

def showmanifest(**args):
    repo, ctx, templ = args['repo'], args['ctx'], args['templ']
    mnode = ctx.manifestnode()
    args = args.copy()
    args.update({'rev': repo.manifest.rev(mnode), 'node': hex(mnode)})
    return templ('manifest', **args)

def shownode(repo, ctx, templ, **args):
    """:node: String. The changeset identification hash, as a 40 hexadecimal
    digit string.
    """
    return ctx.hex()

def showp1rev(repo, ctx, templ, **args):
    """:p1rev: Integer. The repository-local revision number of the changeset's
    first parent, or -1 if the changeset has no parents."""
    return ctx.p1().rev()

def showp2rev(repo, ctx, templ, **args):
    """:p2rev: Integer. The repository-local revision number of the changeset's
    second parent, or -1 if the changeset has no second parent."""
    return ctx.p2().rev()

def showp1node(repo, ctx, templ, **args):
    """:p1node: String. The identification hash of the changeset's first parent,
    as a 40 digit hexadecimal string. If the changeset has no parents, all
    digits are 0."""
    return ctx.p1().hex()

def showp2node(repo, ctx, templ, **args):
    """:p2node: String. The identification hash of the changeset's second
    parent, as a 40 digit hexadecimal string. If the changeset has no second
    parent, all digits are 0."""
    return ctx.p2().hex()

def showphase(repo, ctx, templ, **args):
    """:phase: String. The changeset phase name."""
    return ctx.phasestr()

def showphaseidx(repo, ctx, templ, **args):
    """:phaseidx: Integer. The changeset phase index."""
    return ctx.phase()

def showrev(repo, ctx, templ, **args):
    """:rev: Integer. The repository-local changeset revision number."""
    return ctx.rev()

def showsubrepos(**args):
    """:subrepos: List of strings. Updated subrepositories in the changeset."""
    ctx = args['ctx']
    substate = ctx.substate
    if not substate:
        return showlist('subrepo', [], **args)
    psubstate = ctx.parents()[0].substate or {}
    subrepos = []
    for sub in substate:
        if sub not in psubstate or substate[sub] != psubstate[sub]:
            subrepos.append(sub) # modified or newly added in ctx
    for sub in psubstate:
        if sub not in substate:
            subrepos.append(sub) # removed in ctx
    return showlist('subrepo', sorted(subrepos), **args)

def shownames(namespace, **args):
    """helper method to generate a template keyword for a namespace"""
    ctx = args['ctx']
    repo = ctx.repo()
    ns = repo.names[namespace]
    names = ns.names(repo, ctx.node())
    return showlist(ns.templatename, names, plural=namespace, **args)

# don't remove "showtags" definition, even though namespaces will put
# a helper function for "tags" keyword into "keywords" map automatically,
# because online help text is built without namespaces initialization
def showtags(**args):
    """:tags: List of strings. Any tags associated with the changeset."""
    return shownames('tags', **args)

# keywords are callables like:
# fn(repo, ctx, templ, cache, revcache, **args)
# with:
# repo - current repository instance
# ctx - the changectx being displayed
# templ - the templater instance
# cache - a cache dictionary for the whole templater run
# revcache - a cache dictionary for the current revision
keywords = {
    'author': showauthor,
    'bisect': showbisect,
    'branch': showbranch,
    'branches': showbranches,
    'bookmarks': showbookmarks,
    'children': showchildren,
    'currentbookmark': showcurrentbookmark,
    'date': showdate,
    'desc': showdescription,
    'diffstat': showdiffstat,
    'extras': showextras,
    'file_adds': showfileadds,
    'file_copies': showfilecopies,
    'file_copies_switch': showfilecopiesswitch,
    'file_dels': showfiledels,
    'file_mods': showfilemods,
    'files': showfiles,
    'latesttag': showlatesttag,
    'latesttagdistance': showlatesttagdistance,
    'manifest': showmanifest,
    'node': shownode,
    'p1rev': showp1rev,
    'p1node': showp1node,
    'p2rev': showp2rev,
    'p2node': showp2node,
    'phase': showphase,
    'phaseidx': showphaseidx,
    'rev': showrev,
    'subrepos': showsubrepos,
    'tags': showtags,
}

def _showparents(**args):
    """:parents: List of strings. The parents of the changeset in "rev:node"
    format. If the changeset has only one "natural" parent (the predecessor
    revision) nothing is shown."""
    pass

dockeywords = {
    'parents': _showparents,
}
dockeywords.update(keywords)
del dockeywords['branches']

# tell hggettext to extract docstrings from these functions:
i18nfunctions = dockeywords.values()