view mercurial/templatekw.py @ 29304:5e32852fa4bd

revset: make filteredset.__nonzero__ respect the order of the filteredset

This fix allows __nonzero__ to respect the direction of iteration of the
whole filteredset. Here's the case when it matters. Imagine that we have a
very large repository and we want to execute a command like:

    $ hg log --rev '(tip:0) and user(ikostia)' --limit 1

(we want to get the latest commit by me).

Mercurial will evaluate a filteredset lazy data structure, an
instance of the filteredset class, which will know that it has to iterate
in a descending order (isdescending() will return True if called). This
means that when some code iterates over the instance of this filteredset,
the 'and user(ikostia)' condition will be first checked on the latest
revision, then on the second latest and so on, allowing Mercurial to
print matches as it founds them. However, cmdutil.getgraphlogrevs
contains the following code:

    revs = _logrevs(repo, opts)
    if not revs:
        return revset.baseset(), None, None

The "not revs" expression is evaluated by calling filteredset.__nonzero__,
which in its current implementation will try to iterate the filteredset
in ascending order until it finds a revision that matches the 'and user(..'
condition. If the condition is only true on late revisions, a lot of
useless iterations will be done. These iterations could be avoided if
__nonzero__ followed the order of the filteredset, which in my opinion
is a sensible thing to do here.

The problem gets even worse when instead of 'user(ikostia)' some more
expensive check is performed, like grepping the commit diff.


I tested this fix on a very large repo where tip is my commit and my very
first commit comes fairly late in the revision history. Results of timing
of the above command on that very large repo.

-with my fix:
real    0m1.795s
user    0m1.657s
sys     0m0.135s

-without my fix:
real    1m29.245s
user    1m28.223s
sys     0m0.929s

I understand that this is a very specific kind of problem that presents
itself very rarely, only on very big repositories and with expensive
checks and so on. But I don't see any disadvantages to this kind of fix
either.

# 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 __future__ import absolute_import

from .node import hex, nullid
from . import (
    encoding,
    error,
    hbisect,
    patch,
    registrar,
    scmutil,
    util,
)

# 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 itermaps(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, separator=' ', **args):
    if not element:
        element = name
    f = _showlist(name, values, plural, separator, **args)
    return _hybrid(f, values, lambda x: {element: x})

def _showlist(name, values, plural=None, separator=' ', **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'.
    separator is used to join values as a string

    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 'separator'.

    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 separator.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(), ctx)[:3]
    return revcache['files']

def getlatesttags(repo, ctx, cache, pattern=None):
    '''return date, distance and name for the latest tag of rev'''

    cachename = 'latesttags'
    if pattern is not None:
        cachename += '-' + pattern
        match = util.stringmatcher(pattern)[2]
    else:
        match = util.always

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

    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'
                    and match(t))]
        if tags:
            latesttags[rev] = ctx.date()[0], 0, [t for t in 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

# 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 = {}

templatekeyword = registrar.templatekeyword(keywords)

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

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

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

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

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

@templatekeyword('children')
def showchildren(**args):
    """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)

# Deprecated, but kept alive for help generation a purpose.
@templatekeyword('currentbookmark')
def showcurrentbookmark(**args):
    """String. The active bookmark, if it is
    associated with the changeset (DEPRECATED)"""
    return showactivebookmark(**args)

@templatekeyword('activebookmark')
def showactivebookmark(**args):
    """String. The active bookmark, if it is
    associated with the changeset"""
    active = args['repo']._activebookmark
    if active and active in args['ctx'].bookmarks():
        return active
    return ''

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

@templatekeyword('desc')
def showdescription(repo, ctx, templ, **args):
    """String. The text of the changeset description."""
    s = ctx.description()
    if isinstance(s, encoding.localstr):
        # try hard to preserve utf-8 bytes
        return encoding.tolocal(encoding.fromlocal(s).strip())
    else:
        return s.strip()

@templatekeyword('diffstat')
def showdiffstat(repo, ctx, templ, **args):
    """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)

@templatekeyword('extras')
def showextras(**args):
    """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']))

@templatekeyword('file_adds')
def showfileadds(**args):
    """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)

@templatekeyword('file_copies')
def showfilecopies(**args):
    """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.
@templatekeyword('file_copies_switch')
def showfilecopiesswitch(**args):
    """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']))

@templatekeyword('file_dels')
def showfiledels(**args):
    """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)

@templatekeyword('file_mods')
def showfilemods(**args):
    """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)

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

@templatekeyword('graphnode')
def showgraphnode(repo, ctx, **args):
    """String. The character representing the changeset node in
    an ASCII revision graph"""
    wpnodes = repo.dirstate.parents()
    if wpnodes[1] == nullid:
        wpnodes = wpnodes[:1]
    if ctx.node() in wpnodes:
        return '@'
    elif ctx.obsolete():
        return 'x'
    elif ctx.closesbranch():
        return '_'
    else:
        return 'o'

@templatekeyword('latesttag')
def showlatesttag(**args):
    """List of strings. The global tags on the most recent globally
    tagged ancestor of this changeset.
    """
    return showlatesttags(None, **args)

def showlatesttags(pattern, **args):
    """helper method for the latesttag keyword and function"""
    repo, ctx = args['repo'], args['ctx']
    cache = args['cache']
    latesttags = getlatesttags(repo, ctx, cache, pattern)

    # latesttag[0] is an implementation detail for sorting csets on different
    # branches in a stable manner- it is the date the tagged cset was created,
    # not the date the tag was created.  Therefore it isn't made visible here.
    makemap = lambda v: {
        'changes': _showchangessincetag,
        'distance': latesttags[1],
        'latesttag': v,   # BC with {latesttag % '{latesttag}'}
        'tag': v
    }

    tags = latesttags[2]
    f = _showlist('latesttag', tags, separator=':', **args)
    return _hybrid(f, tags, makemap, lambda x: x['latesttag'])

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

@templatekeyword('changessincelatesttag')
def showchangessincelatesttag(repo, ctx, templ, cache, **args):
    """Integer. All ancestors not in the latest tag."""
    latesttag = getlatesttags(repo, ctx, cache)[2][0]

    return _showchangessincetag(repo, ctx, tag=latesttag, **args)

def _showchangessincetag(repo, ctx, **args):
    offset = 0
    revs = [ctx.rev()]
    tag = args['tag']

    # The only() revset doesn't currently support wdir()
    if ctx.rev() is None:
        offset = 1
        revs = [p.rev() for p in ctx.parents()]

    return len(repo.revs('only(%ld, %s)', revs, tag)) + offset

@templatekeyword('manifest')
def showmanifest(**args):
    repo, ctx, templ = args['repo'], args['ctx'], args['templ']
    mnode = ctx.manifestnode()
    if mnode is None:
        # just avoid crash, we might want to use the 'ff...' hash in future
        return
    args = args.copy()
    args.update({'rev': repo.manifest.rev(mnode), 'node': hex(mnode)})
    return templ('manifest', **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)

@templatekeyword('namespaces')
def shownamespaces(**args):
    """Dict of lists. Names attached to this changeset per
    namespace."""
    ctx = args['ctx']
    repo = ctx.repo()
    namespaces = util.sortdict((k, showlist('name', ns.names(repo, ctx.node()),
                                            **args))
                               for k, ns in repo.names.iteritems())
    f = _showlist('namespace', list(namespaces), **args)
    return _hybrid(f, namespaces,
                   lambda k: {'namespace': k, 'names': namespaces[k]},
                   lambda x: x['namespace'])

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

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

@templatekeyword('p2rev')
def showp2rev(repo, ctx, templ, **args):
    """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()

@templatekeyword('p1node')
def showp1node(repo, ctx, templ, **args):
    """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()

@templatekeyword('p2node')
def showp2node(repo, ctx, templ, **args):
    """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()

@templatekeyword('parents')
def showparents(**args):
    """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."""
    repo = args['repo']
    ctx = args['ctx']
    pctxs = scmutil.meaningfulparents(repo, ctx)
    prevs = [str(p.rev()) for p in pctxs]  # ifcontains() needs a list of str
    parents = [[('rev', p.rev()),
                ('node', p.hex()),
                ('phase', p.phasestr())]
               for p in pctxs]
    f = _showlist('parent', parents, **args)
    return _hybrid(f, prevs, lambda x: {'ctx': repo[int(x)], 'revcache': {}})

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

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

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

def showrevslist(name, revs, **args):
    """helper to generate a list of revisions in which a mapped template will
    be evaluated"""
    repo = args['ctx'].repo()
    revs = [str(r) for r in revs]  # ifcontains() needs a list of str
    f = _showlist(name, revs, **args)
    return _hybrid(f, revs,
                   lambda x: {name: x, 'ctx': repo[int(x)], 'revcache': {}})

@templatekeyword('subrepos')
def showsubrepos(**args):
    """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)

# 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
@templatekeyword('tags')
def showtags(**args):
    """List of strings. Any tags associated with the changeset."""
    return shownames('tags', **args)

def loadkeyword(ui, extname, registrarobj):
    """Load template keyword from specified registrarobj
    """
    for name, func in registrarobj._table.iteritems():
        keywords[name] = func

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