/mercurial/revset.py

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# revset.py - revision set queries for mercurial
#
# Copyright 2010 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

import re
import parser, util, error, discovery, hbisect, phases
import node
import heapq
import match as matchmod
import ancestor as ancestormod
from i18n import _
import encoding
import obsolete as obsmod
import pathutil
import repoview

def _revancestors(repo, revs, followfirst):
    """Like revlog.ancestors(), but supports followfirst."""
    cut = followfirst and 1 or None
    cl = repo.changelog

    def iterate():
        revqueue, revsnode = None, None
        h = []

        revs.descending()
        revqueue = util.deque(revs)
        if revqueue:
            revsnode = revqueue.popleft()
            heapq.heappush(h, -revsnode)

        seen = set([node.nullrev])
        while h:
            current = -heapq.heappop(h)
            if current not in seen:
                if revsnode and current == revsnode:
                    if revqueue:
                        revsnode = revqueue.popleft()
                        heapq.heappush(h, -revsnode)
                seen.add(current)
                yield current
                for parent in cl.parentrevs(current)[:cut]:
                    if parent != node.nullrev:
                        heapq.heappush(h, -parent)

    return _descgeneratorset(iterate())

def _revdescendants(repo, revs, followfirst):
    """Like revlog.descendants() but supports followfirst."""
    cut = followfirst and 1 or None

    def iterate():
        cl = repo.changelog
        first = min(revs)
        nullrev = node.nullrev
        if first == nullrev:
            # Are there nodes with a null first parent and a non-null
            # second one? Maybe. Do we care? Probably not.
            for i in cl:
                yield i
        else:
            seen = set(revs)
            for i in cl.revs(first + 1):
                for x in cl.parentrevs(i)[:cut]:
                    if x != nullrev and x in seen:
                        seen.add(i)
                        yield i
                        break

    return _ascgeneratorset(iterate())

def _revsbetween(repo, roots, heads):
    """Return all paths between roots and heads, inclusive of both endpoint
    sets."""
    if not roots:
        return baseset([])
    parentrevs = repo.changelog.parentrevs
    visit = baseset(heads)
    reachable = set()
    seen = {}
    minroot = min(roots)
    roots = set(roots)
    # open-code the post-order traversal due to the tiny size of
    # sys.getrecursionlimit()
    while visit:
        rev = visit.pop()
        if rev in roots:
            reachable.add(rev)
        parents = parentrevs(rev)
        seen[rev] = parents
        for parent in parents:
            if parent >= minroot and parent not in seen:
                visit.append(parent)
    if not reachable:
        return baseset([])
    for rev in sorted(seen):
        for parent in seen[rev]:
            if parent in reachable:
                reachable.add(rev)
    return baseset(sorted(reachable))

elements = {
    "(": (20, ("group", 1, ")"), ("func", 1, ")")),
    "~": (18, None, ("ancestor", 18)),
    "^": (18, None, ("parent", 18), ("parentpost", 18)),
    "-": (5, ("negate", 19), ("minus", 5)),
    "::": (17, ("dagrangepre", 17), ("dagrange", 17),
           ("dagrangepost", 17)),
    "..": (17, ("dagrangepre", 17), ("dagrange", 17),
           ("dagrangepost", 17)),
    ":": (15, ("rangepre", 15), ("range", 15), ("rangepost", 15)),
    "not": (10, ("not", 10)),
    "!": (10, ("not", 10)),
    "and": (5, None, ("and", 5)),
    "&": (5, None, ("and", 5)),
    "or": (4, None, ("or", 4)),
    "|": (4, None, ("or", 4)),
    "+": (4, None, ("or", 4)),
    ",": (2, None, ("list", 2)),
    ")": (0, None, None),
    "symbol": (0, ("symbol",), None),
    "string": (0, ("string",), None),
    "end": (0, None, None),
}

keywords = set(['and', 'or', 'not'])

def tokenize(program, lookup=None):
    '''
    Parse a revset statement into a stream of tokens

    Check that @ is a valid unquoted token character (issue3686):
    >>> list(tokenize("@::"))
    [('symbol', '@', 0), ('::', None, 1), ('end', None, 3)]

    '''

    pos, l = 0, len(program)
    while pos < l:
        c = program[pos]
        if c.isspace(): # skip inter-token whitespace
            pass
        elif c == ':' and program[pos:pos + 2] == '::': # look ahead carefully
            yield ('::', None, pos)
            pos += 1 # skip ahead
        elif c == '.' and program[pos:pos + 2] == '..': # look ahead carefully
            yield ('..', None, pos)
            pos += 1 # skip ahead
        elif c in "():,-|&+!~^": # handle simple operators
            yield (c, None, pos)
        elif (c in '"\'' or c == 'r' and
              program[pos:pos + 2] in ("r'", 'r"')): # handle quoted strings
            if c == 'r':
                pos += 1
                c = program[pos]
                decode = lambda x: x
            else:
                decode = lambda x: x.decode('string-escape')
            pos += 1
            s = pos
            while pos < l: # find closing quote
                d = program[pos]
                if d == '\\': # skip over escaped characters
                    pos += 2
                    continue
                if d == c:
                    yield ('string', decode(program[s:pos]), s)
                    break
                pos += 1
            else:
                raise error.ParseError(_("unterminated string"), s)
        # gather up a symbol/keyword
        elif c.isalnum() or c in '._@' or ord(c) > 127:
            s = pos
            pos += 1
            while pos < l: # find end of symbol
                d = program[pos]
                if not (d.isalnum() or d in "-._/@" or ord(d) > 127):
                    break
                if d == '.' and program[pos - 1] == '.': # special case for ..
                    pos -= 1
                    break
                pos += 1
            sym = program[s:pos]
            if sym in keywords: # operator keywords
                yield (sym, None, s)
            elif '-' in sym:
                # some jerk gave us foo-bar-baz, try to check if it's a symbol
                if lookup and lookup(sym):
                    # looks like a real symbol
                    yield ('symbol', sym, s)
                else:
                    # looks like an expression
                    parts = sym.split('-')
                    for p in parts[:-1]:
                        if p: # possible consecutive -
                            yield ('symbol', p, s)
                        s += len(p)
                        yield ('-', None, pos)
                        s += 1
                    if parts[-1]: # possible trailing -
                        yield ('symbol', parts[-1], s)
            else:
                yield ('symbol', sym, s)
            pos -= 1
        else:
            raise error.ParseError(_("syntax error"), pos)
        pos += 1
    yield ('end', None, pos)

# helpers

def getstring(x, err):
    if x and (x[0] == 'string' or x[0] == 'symbol'):
        return x[1]
    raise error.ParseError(err)

def getlist(x):
    if not x:
        return []
    if x[0] == 'list':
        return getlist(x[1]) + [x[2]]
    return [x]

def getargs(x, min, max, err):
    l = getlist(x)
    if len(l) < min or (max >= 0 and len(l) > max):
        raise error.ParseError(err)
    return l

def getset(repo, subset, x):
    if not x:
        raise error.ParseError(_("missing argument"))
    s = methods[x[0]](repo, subset, *x[1:])
    if util.safehasattr(s, 'set'):
        return s
    return baseset(s)

def _getrevsource(repo, r):
    extra = repo[r].extra()
    for label in ('source', 'transplant_source', 'rebase_source'):
        if label in extra:
            try:
                return repo[extra[label]].rev()
            except error.RepoLookupError:
                pass
    return None

# operator methods

def stringset(repo, subset, x):
    x = repo[x].rev()
    if x == -1 and len(subset) == len(repo):
        return baseset([-1])
    if len(subset) == len(repo) or x in subset:
        return baseset([x])
    return baseset([])

def symbolset(repo, subset, x):
    if x in symbols:
        raise error.ParseError(_("can't use %s here") % x)
    return stringset(repo, subset, x)

def rangeset(repo, subset, x, y):
    cl = baseset(repo.changelog)
    m = getset(repo, cl, x)
    n = getset(repo, cl, y)

    if not m or not n:
        return baseset([])
    m, n = m[0], n[-1]

    if m < n:
        r = spanset(repo, m, n + 1)
    else:
        r = spanset(repo, m, n - 1)
    return r & subset

def dagrange(repo, subset, x, y):
    r = spanset(repo)
    xs = _revsbetween(repo, getset(repo, r, x), getset(repo, r, y))
    s = subset.set()
    return xs.filter(s.__contains__)

def andset(repo, subset, x, y):
    return getset(repo, getset(repo, subset, x), y)

def orset(repo, subset, x, y):
    xl = getset(repo, subset, x)
    yl = getset(repo, subset - xl, y)
    return xl + yl

def notset(repo, subset, x):
    return subset - getset(repo, subset, x)

def listset(repo, subset, a, b):
    raise error.ParseError(_("can't use a list in this context"))

def func(repo, subset, a, b):
    if a[0] == 'symbol' and a[1] in symbols:
        return symbols[a[1]](repo, subset, b)
    raise error.ParseError(_("not a function: %s") % a[1])

# functions

def adds(repo, subset, x):
    """``adds(pattern)``
    Changesets that add a file matching pattern.

    The pattern without explicit kind like ``glob:`` is expected to be
    relative to the current directory and match against a file or a
    directory.
    """
    # i18n: "adds" is a keyword
    pat = getstring(x, _("adds requires a pattern"))
    return checkstatus(repo, subset, pat, 1)

def ancestor(repo, subset, x):
    """``ancestor(*changeset)``
    A greatest common ancestor of the changesets.

    Accepts 0 or more changesets.
    Will return empty list when passed no args.
    Greatest common ancestor of a single changeset is that changeset.
    """
    # i18n: "ancestor" is a keyword
    l = getlist(x)
    rl = spanset(repo)
    anc = None

    # (getset(repo, rl, i) for i in l) generates a list of lists
    for revs in (getset(repo, rl, i) for i in l):
        for r in revs:
            if anc is None:
                anc = repo[r]
            else:
                anc = anc.ancestor(repo[r])

    if anc is not None and anc.rev() in subset:
        return baseset([anc.rev()])
    return baseset([])

def _ancestors(repo, subset, x, followfirst=False):
    args = getset(repo, spanset(repo), x)
    if not args:
        return baseset([])
    s = _revancestors(repo, args, followfirst)
    return subset.filter(s.__contains__)

def ancestors(repo, subset, x):
    """``ancestors(set)``
    Changesets that are ancestors of a changeset in set.
    """
    return _ancestors(repo, subset, x)

def _firstancestors(repo, subset, x):
    # ``_firstancestors(set)``
    # Like ``ancestors(set)`` but follows only the first parents.
    return _ancestors(repo, subset, x, followfirst=True)

def ancestorspec(repo, subset, x, n):
    """``set~n``
    Changesets that are the Nth ancestor (first parents only) of a changeset
    in set.
    """
    try:
        n = int(n[1])
    except (TypeError, ValueError):
        raise error.ParseError(_("~ expects a number"))
    ps = set()
    cl = repo.changelog
    for r in getset(repo, baseset(cl), x):
        for i in range(n):
            r = cl.parentrevs(r)[0]
        ps.add(r)
    return subset.filter(ps.__contains__)

def author(repo, subset, x):
    """``author(string)``
    Alias for ``user(string)``.
    """
    # i18n: "author" is a keyword
    n = encoding.lower(getstring(x, _("author requires a string")))
    kind, pattern, matcher = _substringmatcher(n)
    return subset.filter(lambda x: matcher(encoding.lower(repo[x].user())))

def only(repo, subset, x):
    """``only(set, [set])``
    Changesets that are ancestors of the first set that are not ancestors
    of any other head in the repo. If a second set is specified, the result
    is ancestors of the first set that are not ancestors of the second set
    (i.e. ::<set1> - ::<set2>).
    """
    cl = repo.changelog
    # i18n: "only" is a keyword
    args = getargs(x, 1, 2, _('only takes one or two arguments'))
    include = getset(repo, spanset(repo), args[0]).set()
    if len(args) == 1:
        descendants = set(_revdescendants(repo, include, False))
        exclude = [rev for rev in cl.headrevs()
            if not rev in descendants and not rev in include]
    else:
        exclude = getset(repo, spanset(repo), args[1])

    results = set(ancestormod.missingancestors(include, exclude, cl.parentrevs))
    return lazyset(subset, results.__contains__)

def bisect(repo, subset, x):
    """``bisect(string)``
    Changesets marked in the specified bisect status:

    - ``good``, ``bad``, ``skip``: csets explicitly marked as good/bad/skip
    - ``goods``, ``bads``      : csets topologically good/bad
    - ``range``              : csets taking part in the bisection
    - ``pruned``             : csets that are goods, bads or skipped
    - ``untested``           : csets whose fate is yet unknown
    - ``ignored``            : csets ignored due to DAG topology
    - ``current``            : the cset currently being bisected
    """
    # i18n: "bisect" is a keyword
    status = getstring(x, _("bisect requires a string")).lower()
    state = set(hbisect.get(repo, status))
    return subset.filter(state.__contains__)

# Backward-compatibility
# - no help entry so that we do not advertise it any more
def bisected(repo, subset, x):
    return bisect(repo, subset, x)

def bookmark(repo, subset, x):
    """``bookmark([name])``
    The named bookmark or all bookmarks.

    If `name` starts with `re:`, the remainder of the name is treated as
    a regular expression. To match a bookmark that actually starts with `re:`,
    use the prefix `literal:`.
    """
    # i18n: "bookmark" is a keyword
    args = getargs(x, 0, 1, _('bookmark takes one or no arguments'))
    if args:
        bm = getstring(args[0],
                       # i18n: "bookmark" is a keyword
                       _('the argument to bookmark must be a string'))
        kind, pattern, matcher = _stringmatcher(bm)
        if kind == 'literal':
            bmrev = repo._bookmarks.get(bm, None)
            if not bmrev:
                raise util.Abort(_("bookmark '%s' does not exist") % bm)
            bmrev = repo[bmrev].rev()
            return subset.filter(lambda r: r == bmrev)
        else:
            matchrevs = set()
            for name, bmrev in repo._bookmarks.iteritems():
                if matcher(name):
                    matchrevs.add(bmrev)
            if not matchrevs:
                raise util.Abort(_("no bookmarks exist that match '%s'")
                                 % pattern)
            bmrevs = set()
            for bmrev in matchrevs:
                bmrevs.add(repo[bmrev].rev())
            return subset & bmrevs

    bms = set([repo[r].rev()
               for r in repo._bookmarks.values()])
    return subset.filter(bms.__contains__)

def branch(repo, subset, x):
    """``branch(string or set)``
    All changesets belonging to the given branch or the branches of the given
    changesets.

    If `string` starts with `re:`, the remainder of the name is treated as
    a regular expression. To match a branch that actually starts with `re:`,
    use the prefix `literal:`.
    """
    try:
        b = getstring(x, '')
    except error.ParseError:
        # not a string, but another revspec, e.g. tip()
        pass
    else:
        kind, pattern, matcher = _stringmatcher(b)
        if kind == 'literal':
            # note: falls through to the revspec case if no branch with
            # this name exists
            if pattern in repo.branchmap():
                return subset.filter(lambda r: matcher(repo[r].branch()))
        else:
            return subset.filter(lambda r: matcher(repo[r].branch()))

    s = getset(repo, spanset(repo), x)
    b = set()
    for r in s:
        b.add(repo[r].branch())
    s = s.set()
    return subset.filter(lambda r: r in s or repo[r].branch() in b)

def bumped(repo, subset, x):
    """``bumped()``
    Mutable changesets marked as successors of public changesets.

    Only non-public and non-obsolete changesets can be `bumped`.
    """
    # i18n: "bumped" is a keyword
    getargs(x, 0, 0, _("bumped takes no arguments"))
    bumped = obsmod.getrevs(repo, 'bumped')
    return subset & bumped

def bundle(repo, subset, x):
    """``bundle()``
    Changesets in the bundle.

    Bundle must be specified by the -R option."""

    try:
        bundlerevs = repo.changelog.bundlerevs
    except AttributeError:
        raise util.Abort(_("no bundle provided - specify with -R"))
    return subset & bundlerevs

def checkstatus(repo, subset, pat, field):
    hasset = matchmod.patkind(pat) == 'set'

    def matches(x):
        m = None
        fname = None
        c = repo[x]
        if not m or hasset:
            m = matchmod.match(repo.root, repo.getcwd(), [pat], ctx=c)
            if not m.anypats() and len(m.files()) == 1:
                fname = m.files()[0]
        if fname is not None:
            if fname not in c.files():
                return False
        else:
            for f in c.files():
                if m(f):
                    break
            else:
                return False
        files = repo.status(c.p1().node(), c.node())[field]
        if fname is not None:
            if fname in files:
                return True
        else:
            for f in files:
                if m(f):
                    return True

    return subset.filter(matches)

def _children(repo, narrow, parentset):
    cs = set()
    if not parentset:
        return baseset(cs)
    pr = repo.changelog.parentrevs
    minrev = min(parentset)
    for r in narrow:
        if r <= minrev:
            continue
        for p in pr(r):
            if p in parentset:
                cs.add(r)
    return baseset(cs)

def children(repo, subset, x):
    """``children(set)``
    Child changesets of changesets in set.
    """
    s = getset(repo, baseset(repo), x).set()
    cs = _children(repo, subset, s)
    return subset & cs

def closed(repo, subset, x):
    """``closed()``
    Changeset is closed.
    """
    # i18n: "closed" is a keyword
    getargs(x, 0, 0, _("closed takes no arguments"))
    return subset.filter(lambda r: repo[r].closesbranch())

def contains(repo, subset, x):
    """``contains(pattern)``
    The revision's manifest contains a file matching pattern (but might not
    modify it). See :hg:`help patterns` for information about file patterns.

    The pattern without explicit kind like ``glob:`` is expected to be
    relative to the current directory and match against a file exactly
    for efficiency.
    """
    # i18n: "contains" is a keyword
    pat = getstring(x, _("contains requires a pattern"))

    def matches(x):
        if not matchmod.patkind(pat):
            pats = pathutil.canonpath(repo.root, repo.getcwd(), pat)
            if pats in repo[x]:
                return True
        else:
            c = repo[x]
            m = matchmod.match(repo.root, repo.getcwd(), [pat], ctx=c)
            for f in c.manifest():
                if m(f):
                    return True
        return False

    return subset.filter(matches)

def converted(repo, subset, x):
    """``converted([id])``
    Changesets converted from the given identifier in the old repository if
    present, or all converted changesets if no identifier is specified.
    """

    # There is exactly no chance of resolving the revision, so do a simple
    # string compare and hope for the best

    rev = None
    # i18n: "converted" is a keyword
    l = getargs(x, 0, 1, _('converted takes one or no arguments'))
    if l:
        # i18n: "converted" is a keyword
        rev = getstring(l[0], _('converted requires a revision'))

    def _matchvalue(r):
        source = repo[r].extra().get('convert_revision', None)
        return source is not None and (rev is None or source.startswith(rev))

    return subset.filter(lambda r: _matchvalue(r))

def date(repo, subset, x):
    """``date(interval)``
    Changesets within the interval, see :hg:`help dates`.
    """
    # i18n: "date" is a keyword
    ds = getstring(x, _("date requires a string"))
    dm = util.matchdate(ds)
    return subset.filter(lambda x: dm(repo[x].date()[0]))

def desc(repo, subset, x):
    """``desc(string)``
    Search commit message for string. The match is case-insensitive.
    """
    # i18n: "desc" is a keyword
    ds = encoding.lower(getstring(x, _("desc requires a string")))

    def matches(x):
        c = repo[x]
        return ds in encoding.lower(c.description())

    return subset.filter(matches)

def _descendants(repo, subset, x, followfirst=False):
    args = getset(repo, spanset(repo), x)
    if not args:
        return baseset([])
    s = _revdescendants(repo, args, followfirst)

    # Both sets need to be ascending in order to lazily return the union
    # in the correct order.
    args.ascending()

    subsetset = subset.set()
    result = (orderedlazyset(s, subsetset.__contains__, ascending=True) +
              orderedlazyset(args, subsetset.__contains__, ascending=True))

    # Wrap result in a lazyset since it's an _addset, which doesn't implement
    # all the necessary functions to be consumed by callers.
    return orderedlazyset(result, lambda r: True, ascending=True)

def descendants(repo, subset, x):
    """``descendants(set)``
    Changesets which are descendants of changesets in set.
    """
    return _descendants(repo, subset, x)

def _firstdescendants(repo, subset, x):
    # ``_firstdescendants(set)``
    # Like ``descendants(set)`` but follows only the first parents.
    return _descendants(repo, subset, x, followfirst=True)

def destination(repo, subset, x):
    """``destination([set])``
    Changesets that were created by a graft, transplant or rebase operation,
    with the given revisions specified as the source.  Omitting the optional set
    is the same as passing all().
    """
    if x is not None:
        args = getset(repo, spanset(repo), x).set()
    else:
        args = getall(repo, spanset(repo), x).set()

    dests = set()

    # subset contains all of the possible destinations that can be returned, so
    # iterate over them and see if their source(s) were provided in the args.
    # Even if the immediate src of r is not in the args, src's source (or
    # further back) may be.  Scanning back further than the immediate src allows
    # transitive transplants and rebases to yield the same results as transitive
    # grafts.
    for r in subset:
        src = _getrevsource(repo, r)
        lineage = None

        while src is not None:
            if lineage is None:
                lineage = list()

            lineage.append(r)

            # The visited lineage is a match if the current source is in the arg
            # set.  Since every candidate dest is visited by way of iterating
            # subset, any dests further back in the lineage will be tested by a
            # different iteration over subset.  Likewise, if the src was already
            # selected, the current lineage can be selected without going back
            # further.
            if src in args or src in dests:
                dests.update(lineage)
                break

            r = src
            src = _getrevsource(repo, r)

    return subset.filter(dests.__contains__)

def divergent(repo, subset, x):
    """``divergent()``
    Final successors of changesets with an alternative set of final successors.
    """
    # i18n: "divergent" is a keyword
    getargs(x, 0, 0, _("divergent takes no arguments"))
    divergent = obsmod.getrevs(repo, 'divergent')
    return subset.filter(divergent.__contains__)

def draft(repo, subset, x):
    """``draft()``
    Changeset in draft phase."""
    # i18n: "draft" is a keyword
    getargs(x, 0, 0, _("draft takes no arguments"))
    pc = repo._phasecache
    return subset.filter(lambda r: pc.phase(repo, r) == phases.draft)

def extinct(repo, subset, x):
    """``extinct()``
    Obsolete changesets with obsolete descendants only.
    """
    # i18n: "extinct" is a keyword
    getargs(x, 0, 0, _("extinct takes no arguments"))
    extincts = obsmod.getrevs(repo, 'extinct')
    return subset & extincts

def extra(repo, subset, x):
    """``extra(label, [value])``
    Changesets with the given label in the extra metadata, with the given
    optional value.

    If `value` starts with `re:`, the remainder of the value is treated as
    a regular expression. To match a value that actually starts with `re:`,
    use the prefix `literal:`.
    """

    # i18n: "extra" is a keyword
    l = getargs(x, 1, 2, _('extra takes at least 1 and at most 2 arguments'))
    # i18n: "extra" is a keyword
    label = getstring(l[0], _('first argument to extra must be a string'))
    value = None

    if len(l) > 1:
        # i18n: "extra" is a keyword
        value = getstring(l[1], _('second argument to extra must be a string'))
        kind, value, matcher = _stringmatcher(value)

    def _matchvalue(r):
        extra = repo[r].extra()
        return label in extra and (value is None or matcher(extra[label]))

    return subset.filter(lambda r: _matchvalue(r))

def filelog(repo, subset, x):
    """``filelog(pattern)``
    Changesets connected to the specified filelog.

    For performance reasons, visits only revisions mentioned in the file-level
    filelog, rather than filtering through all changesets (much faster, but
    doesn't include deletes or duplicate changes). For a slower, more accurate
    result, use ``file()``.

    The pattern without explicit kind like ``glob:`` is expected to be
    relative to the current directory and match against a file exactly
    for efficiency.
    """

    # i18n: "filelog" is a keyword
    pat = getstring(x, _("filelog requires a pattern"))
    s = set()

    if not matchmod.patkind(pat):
        f = pathutil.canonpath(repo.root, repo.getcwd(), pat)
        fl = repo.file(f)
        for fr in fl:
            s.add(fl.linkrev(fr))
    else:
        m = matchmod.match(repo.root, repo.getcwd(), [pat], ctx=repo[None])
        for f in repo[None]:
            if m(f):
                fl = repo.file(f)
                for fr in fl:
                    s.add(fl.linkrev(fr))

    return subset.filter(s.__contains__)

def first(repo, subset, x):
    """``first(set, [n])``
    An alias for limit().
    """
    return limit(repo, subset, x)

def _follow(repo, subset, x, name, followfirst=False):
    l = getargs(x, 0, 1, _("%s takes no arguments or a filename") % name)
    c = repo['.']
    if l:
        x = getstring(l[0], _("%s expected a filename") % name)
        if x in c:
            cx = c[x]
            s = set(ctx.rev() for ctx in cx.ancestors(followfirst=followfirst))
            # include the revision responsible for the most recent version
            s.add(cx.linkrev())
        else:
            return baseset([])
    else:
        s = _revancestors(repo, baseset([c.rev()]), followfirst)

    return subset.filter(s.__contains__)

def follow(repo, subset, x):
    """``follow([file])``
    An alias for ``::.`` (ancestors of the working copy's first parent).
    If a filename is specified, the history of the given file is followed,
    including copies.
    """
    return _follow(repo, subset, x, 'follow')

def _followfirst(repo, subset, x):
    # ``followfirst([file])``
    # Like ``follow([file])`` but follows only the first parent of
    # every revision or file revision.
    return _follow(repo, subset, x, '_followfirst', followfirst=True)

def getall(repo, subset, x):
    """``all()``
    All changesets, the same as ``0:tip``.
    """
    # i18n: "all" is a keyword
    getargs(x, 0, 0, _("all takes no arguments"))
    return subset

def grep(repo, subset, x):
    """``grep(regex)``
    Like ``keyword(string)`` but accepts a regex. Use ``grep(r'...')``
    to ensure special escape characters are handled correctly. Unlike
    ``keyword(string)``, the match is case-sensitive.
    """
    try:
        # i18n: "grep" is a keyword
        gr = re.compile(getstring(x, _("grep requires a string")))
    except re.error, e:
        raise error.ParseError(_('invalid match pattern: %s') % e)

    def matches(x):
        c = repo[x]
        for e in c.files() + [c.user(), c.description()]:
            if gr.search(e):
                return True
        return False

    return subset.filter(matches)

def _matchfiles(repo, subset, x):
    # _matchfiles takes a revset list of prefixed arguments:
    #
    #   [p:foo, i:bar, x:baz]
    #
    # builds a match object from them and filters subset. Allowed
    # prefixes are 'p:' for regular patterns, 'i:' for include
    # patterns and 'x:' for exclude patterns. Use 'r:' prefix to pass
    # a revision identifier, or the empty string to reference the
    # working directory, from which the match object is
    # initialized. Use 'd:' to set the default matching mode, default
    # to 'glob'. At most one 'r:' and 'd:' argument can be passed.

    # i18n: "_matchfiles" is a keyword
    l = getargs(x, 1, -1, _("_matchfiles requires at least one argument"))
    pats, inc, exc = [], [], []
    hasset = False
    rev, default = None, None
    for arg in l:
        # i18n: "_matchfiles" is a keyword
        s = getstring(arg, _("_matchfiles requires string arguments"))
        prefix, value = s[:2], s[2:]
        if prefix == 'p:':
            pats.append(value)
        elif prefix == 'i:':
            inc.append(value)
        elif prefix == 'x:':
            exc.append(value)
        elif prefix == 'r:':
            if rev is not None:
                # i18n: "_matchfiles" is a keyword
                raise error.ParseError(_('_matchfiles expected at most one '
                                         'revision'))
            rev = value
        elif prefix == 'd:':
            if default is not None:
                # i18n: "_matchfiles" is a keyword
                raise error.ParseError(_('_matchfiles expected at most one '
                                         'default mode'))
            default = value
        else:
            # i18n: "_matchfiles" is a keyword
            raise error.ParseError(_('invalid _matchfiles prefix: %s') % prefix)
        if not hasset and matchmod.patkind(value) == 'set':
            hasset = True
    if not default:
        default = 'glob'

    def matches(x):
        m = None
        c = repo[x]
        if not m or (hasset and rev is None):
            ctx = c
            if rev is not None:
                ctx = repo[rev or None]
            m = matchmod.match(repo.root, repo.getcwd(), pats, include=inc,
                               exclude=exc, ctx=ctx, default=default)
        for f in c.files():
            if m(f):
                return True
        return False

    return subset.filter(matches)

def hasfile(repo, subset, x):
    """``file(pattern)``
    Changesets affecting files matched by pattern.

    For a faster but less accurate result, consider using ``filelog()``
    instead.

    This predicate uses ``glob:`` as the default kind of pattern.
    """
    # i18n: "file" is a keyword
    pat = getstring(x, _("file requires a pattern"))
    return _matchfiles(repo, subset, ('string', 'p:' + pat))

def head(repo, subset, x):
    """``head()``
    Changeset is a named branch head.
    """
    # i18n: "head" is a keyword
    getargs(x, 0, 0, _("head takes no arguments"))
    hs = set()
    for b, ls in repo.branchmap().iteritems():
        hs.update(repo[h].rev() for h in ls)
    return baseset(hs).filter(subset.__contains__)

def heads(repo, subset, x):
    """``heads(set)``
    Members of set with no children in set.
    """
    s = getset(repo, subset, x)
    ps = parents(repo, subset, x)
    return s - ps

def hidden(repo, subset, x):
    """``hidden()``
    Hidden changesets.
    """
    # i18n: "hidden" is a keyword
    getargs(x, 0, 0, _("hidden takes no arguments"))
    hiddenrevs = repoview.filterrevs(repo, 'visible')
    return subset & hiddenrevs

def keyword(repo, subset, x):
    """``keyword(string)``
    Search commit message, user name, and names of changed files for
    string. The match is case-insensitive.
    """
    # i18n: "keyword" is a keyword
    kw = encoding.lower(getstring(x, _("keyword requires a string")))

    def matches(r):
        c = repo[r]
        return util.any(kw in encoding.lower(t) for t in c.files() + [c.user(),
            c.description()])

    return subset.filter(matches)

def limit(repo, subset, x):
    """``limit(set, [n])``
    First n members of set, defaulting to 1.
    """
    # i18n: "limit" is a keyword
    l = getargs(x, 1, 2, _("limit requires one or two arguments"))
    try:
        lim = 1
        if len(l) == 2:
            # i18n: "limit" is a keyword
            lim = int(getstring(l[1], _("limit requires a number")))
    except (TypeError, ValueError):
        # i18n: "limit" is a keyword
        raise error.ParseError(_("limit expects a number"))
    ss = subset.set()
    os = getset(repo, spanset(repo), l[0])
    bs = baseset([])
    it = iter(os)
    for x in xrange(lim):
        try:
            y = it.next()
            if y in ss:
                bs.append(y)
        except (StopIteration):
            break
    return bs

def last(repo, subset, x):
    """``last(set, [n])``
    Last n members of set, defaulting to 1.
    """
    # i18n: "last" is a keyword
    l = getargs(x, 1, 2, _("last requires one or two arguments"))
    try:
        lim = 1
        if len(l) == 2:
            # i18n: "last" is a keyword
            lim = int(getstring(l[1], _("last requires a number")))
    except (TypeError, ValueError):
        # i18n: "last" is a keyword
        raise error.ParseError(_("last expects a number"))
    ss = subset.set()
    os = getset(repo, spanset(repo), l[0])
    os.reverse()
    bs = baseset([])
    it = iter(os)
    for x in xrange(lim):
        try:
            y = it.next()
            if y in ss:
                bs.append(y)
        except (StopIteration):
            break
    return bs

def maxrev(repo, subset, x):
    """``max(set)``
    Changeset with highest revision number in set.
    """
    os = getset(repo, spanset(repo), x)
    if os:
        m = os.max()
        if m in subset:
            return baseset([m])
    return baseset([])

def merge(repo, subset, x):
    """``merge()``
    Changeset is a merge changeset.
    """
    # i18n: "merge" is a keyword
    getargs(x, 0, 0, _("merge takes no arguments"))
    cl = repo.changelog
    return subset.filter(lambda r: cl.parentrevs(r)[1] != -1)

def branchpoint(repo, subset, x):
    """``branchpoint()``
    Changesets with more than one child.
    """
    # i18n: "branchpoint" is a keyword
    getargs(x, 0, 0, _("branchpoint takes no arguments"))
    cl = repo.changelog
    if not subset:
        return baseset([])
    baserev = min(subset)
    parentscount = [0]*(len(repo) - baserev)
    for r in cl.revs(start=baserev + 1):
        for p in cl.parentrevs(r):
            if p >= baserev:
                parentscount[p - baserev] += 1
    return subset.filter(lambda r: parentscount[r - baserev] > 1)

def minrev(repo, subset, x):
    """``min(set)``
    Changeset with lowest revision number in set.
    """
    os = getset(repo, spanset(repo), x)
    if os:
        m = os.min()
        if m in subset:
            return baseset([m])
    return baseset([])

def _missingancestors(repo, subset, x):
    # i18n: "_missingancestors" is a keyword
    revs, bases = getargs(x, 2, 2,
                          _("_missingancestors requires two arguments"))
    rs = baseset(repo)
    revs = getset(repo, rs, revs)
    bases = getset(repo, rs, bases)
    missing = set(repo.changelog.findmissingrevs(bases, revs))
    return baseset([r for r in subset if r in missing])

def modifies(repo, subset, x):
    """``modifies(pattern)``
    Changesets modifying files matched by pattern.

    The pattern without explicit kind like ``glob:`` is expected to be
    relative to the current directory and match against a file or a
    directory.
    """
    # i18n: "modifies" is a keyword
    pat = getstring(x, _("modifies requires a pattern"))
    return checkstatus(repo, subset, pat, 0)

def node_(repo, subset, x):
    """``id(string)``
    Revision non-ambiguously specified by the given hex string prefix.
    """
    # i18n: "id" is a keyword
    l = getargs(x, 1, 1, _("id requires one argument"))
    # i18n: "id" is a keyword
    n = getstring(l[0], _("id requires a string"))
    if len(n) == 40:
        rn = repo[n].rev()
    else:
        rn = None
        pm = repo.changelog._partialmatch(n)
        if pm is not None:
            rn = repo.changelog.rev(pm)

    return subset.filter(lambda r: r == rn)

def obsolete(repo, subset, x):
    """``obsolete()``
    Mutable changeset with a newer version."""
    # i18n: "obsolete" is a keyword
    getargs(x, 0, 0, _("obsolete takes no arguments"))
    obsoletes = obsmod.getrevs(repo, 'obsolete')
    return subset & obsoletes

def origin(repo, subset, x):
    """``origin([set])``
    Changesets that were specified as a source for the grafts, transplants or
    rebases that created the given revisions.  Omitting the optional set is the
    same as passing all().  If a changeset created by these operations is itself
    specified as a source for one of these operations, only the source changeset
    for the first operation is selected.
    """
    if x is not None:
        args = getset(repo, spanset(repo), x).set()
    else:
        args = getall(repo, spanset(repo), x).set()

    def _firstsrc(rev):
        src = _getrevsource(repo, rev)
        if src is None:
            return None

        while True:
            prev = _getrevsource(repo, src)

            if prev is None:
                return src
            src = prev

    o = set([_firstsrc(r) for r in args])
    return subset.filter(o.__contains__)

def outgoing(repo, subset, x):
    """``outgoing([path])``
    Changesets not found in the specified destination repository, or the
    default push location.
    """
    import hg # avoid start-up nasties
    # i18n: "outgoing" is a keyword
    l = getargs(x, 0, 1, _("outgoing takes one or no arguments"))
    # i18n: "outgoing" is a keyword
    dest = l and getstring(l[0], _("outgoing requires a repository path")) or ''
    dest = repo.ui.expandpath(dest or 'default-push', dest or 'default')
    dest, branches = hg.parseurl(dest)
    revs, checkout = hg.addbranchrevs(repo, repo, branches, [])
    if revs:
        revs = [repo.lookup(rev) for rev in revs]
    other = hg.peer(repo, {}, dest)
    repo.ui.pushbuffer()
    outgoing = discovery.findcommonoutgoing(repo, other, onlyheads=revs)
    repo.ui.popbuffer()
    cl = repo.changelog
    o = set([cl.rev(r) for r in outgoing.missing])
    return subset.filter(o.__contains__)

def p1(repo, subset, x):
    """``p1([set])``
    First parent of changesets in set, or the working directory.
    """
    if x is None:
        p = repo[x].p1().rev()
        return subset.filter(lambda r: r == p)

    ps = set()
    cl = repo.changelog
    for r in getset(repo, spanset(repo), x):
        ps.add(cl.parentrevs(r)[0])
    return subset & ps

def p2(repo, subset, x):
    """``p2([set])``
    Second parent of changesets in set, or the working directory.
    """
    if x is None:
        ps = repo[x].parents()
        try:
            p = ps[1].rev()
            return subset.filter(lambda r: r == p)
        except IndexError:
            return baseset([])

    ps = set()
    cl = repo.changelog
    for r in getset(repo, spanset(repo), x):
        ps.add(cl.parentrevs(r)[1])
    return subset & ps

def parents(repo, subset, x):
    """``parents([set])``
    The set of all parents for all changesets in set, or the working directory.
    """
    if x is None:
        ps = tuple(p.rev() for p in repo[x].parents())
        return subset & ps

    ps = set()
    cl = repo.changelog
    for r in getset(repo, spanset(repo), x):
        ps.update(cl.parentrevs(r))
    return subset & ps

def parentspec(repo, subset, x, n):
    """``set^0``
    The set.
    ``set^1`` (or ``set^``), ``set^2``
    First or second parent, respectively, of all changesets in set.
    """
    try:
        n = int(n[1])
        if n not in (0, 1, 2):
            raise ValueError
    except (TypeError, ValueError):
        raise error.ParseError(_("^ expects a number 0, 1, or 2"))
    ps = set()
    cl = repo.changelog
    for r in getset(repo, baseset(cl), x):
        if n == 0:
            ps.add(r)
        elif n == 1:
            ps.add(cl.parentrevs(r)[0])
        elif n == 2:
            parents = cl.parentrevs(r)
            if len(parents) > 1:
                ps.add(parents[1])
    return subset & ps

def present(repo, subset, x):
    """``present(set)``
    An empty set, if any revision in set isn't found; otherwise,
    all revisions in set.

    If any of specified revisions is not present in the local repository,
    the query is normally aborted. But this predicate allows the query
    to continue even in such cases.
    """
    try:
        return getset(repo, subset, x)
    except error.RepoLookupError:
        return baseset([])

def public(repo, subset, x):
    """``public()``
    Changeset in public phase."""
    # i18n: "public" is a keyword
    getargs(x, 0, 0, _("public takes no arguments"))
    pc = repo._phasecache
    return subset.filter(lambda r: pc.phase(repo, r) == phases.public)

def remote(repo, subset, x):
    """``remote([id [,path]])``
    Local revision that corresponds to the given identifier in a
    remote repository, if present. Here, the '.' identifier is a
    synonym for the current local branch.
    """

    import hg # avoid start-up nasties
    # i18n: "remote" is a keyword
    l = getargs(x, 0, 2, _("remote takes one, two or no arguments"))

    q = '.'
    if len(l) > 0:
    # i18n: "remote" is a keyword
        q = getstring(l[0], _("remote requires a string id"))
    if q == '.':
        q = repo['.'].branch()

    dest = ''
    if len(l) > 1:
        # i18n: "remote" is a keyword
        dest = getstring(l[1], _("remote requires a repository path"))
    dest = repo.ui.expandpath(dest or 'default')
    dest, branches = hg.parseurl(dest)
    revs, checkout = hg.addbranchrevs(repo, repo, branches, [])
    if revs:
        revs = [repo.lookup(rev) for rev in revs]
    other = hg.peer(repo, {}, dest)
    n = other.lookup(q)
    if n in repo:
        r = repo[n].rev()
        if r in subset:
            return baseset([r])
    return baseset([])

def removes(repo, subset, x):
    """``removes(pattern)``
    Changesets which remove files matching pattern.

    The pattern without explicit kind like ``glob:`` is expected to be
    relative to the current directory and match against a file or a
    directory.
    """
    # i18n: "removes" is a keyword
    pat = getstring(x, _("removes requires a pattern"))
    return checkstatus(repo, subset, pat, 2)

def rev(repo, subset, x):
    """``rev(number)``
    Revision with the given numeric identifier.
    """
    # i18n: "rev" is a keyword
    l = getargs(x, 1, 1, _("rev requires one argument"))
    try:
        # i18n: "rev" is a keyword
        l = int(getstring(l[0], _("rev requires a number")))
    except (TypeError, ValueError):
        # i18n: "rev" is a keyword
        raise error.ParseError(_("rev expects a number"))
    return subset.filter(lambda r: r == l)

def matching(repo, subset, x):
    """``matching(revision [, field])``
    Changesets in which a given set of fields match the set of fields in the
    selected revision or set.

    To match more than one field pass the list of fields to match separated
    by spaces (e.g. ``author description``).

    Valid fields are most regular revision fields and some special fields.

    Regular revision fields are ``description``, ``author``, ``branch``,
    ``date``, ``files``, ``phase``, ``parents``, ``substate``, ``user``
    and ``diff``.
    Note that ``author`` and ``user`` are synonyms. ``diff`` refers to the
    contents of the revision. Two revisions matching their ``diff`` will
    also match their ``files``.

    Special fields are ``summary`` and ``metadata``:
    ``summary`` matches the first line of the description.
    ``metadata`` is equivalent to matching ``description user date``
    (i.e. it matches the main metadata fields).

    ``metadata`` is the default field which is used when no fields are
    specified. You can match more than one field at a time.
    """
    # i18n: "matching" is a keyword
    l = getargs(x, 1, 2, _("matching takes 1 or 2 arguments"))

    revs = getset(repo, baseset(repo.changelog), l[0])

    fieldlist = ['metadata']
    if len(l) > 1:
            fieldlist = getstring(l[1],
                # i18n: "matching" is a keyword
                _("matching requires a string "
                "as its second argument")).split()

    # Make sure that there are no repeated fields,
    # expand the 'special' 'metadata' field type
    # and check the 'files' whenever we check the 'diff'
    fields = []
    for field in fieldlist:
        if field == 'metadata':
            fields += ['user', 'description', 'date']
        elif field == 'diff':
            # a revision matching the diff must also match the files
            # since matching the diff is very costly, make sure to
            # also match the files first
            fields += ['files', 'diff']
        else:
            if field == 'author':
                field = 'user'
            fields.append(field)
    fields = set(fields)
    if 'summary' in fields and 'description' in fields:
        # If a revision matches its description it also matches its summary
        fields.discard('summary')

    # We may want to match more than one field
    # Not all fields take the same amount of time to be matched
    # Sort the selected fields in order of increasing matching cost
    fieldorder = ['phase', 'parents', 'user', 'date', 'branch', 'summary',
        'files', 'description', 'substate', 'diff']
    def fieldkeyfunc(f):
        try:
            return fieldorder.index(f)
        except ValueError:
            # assume an unknown field is very costly
            return len(fieldorder)
    fields = list(fields)
    fields.sort(key=fieldkeyfunc)

    # Each field will be matched with its own "getfield" function
    # which will be added to the getfieldfuncs array of functions
    getfieldfuncs = []
    _funcs = {
        'user': lambda r: repo[r].user(),
        'branch': lambda r: repo[r].branch(),
        'date': lambda r: repo[r].date(),
        'description': lambda r: repo[r].description(),
        'files': lambda r: repo[r].files(),
        'parents': lambda r: repo[r].parents(),
        'phase': lambda r: repo[r].phase(),
        'substate': lambda r: repo[r].substate,
        'summary': lambda r: repo[r].description().splitlines()[0],
        'diff': lambda r: list(repo[r].diff(git=True),)
    }
    for info in fields:
        getfield = _funcs.get(info, None)
        if getfield is None:
            raise error.ParseError(
                # i18n: "matching" is a keyword
                _("unexpected field name passed to matching: %s") % info)
        getfieldfuncs.append(getfield)
    # convert the getfield array of functions into a "getinfo" function
    # which returns an array of field values (or a single value if there
    # is only one field to match)
    getinfo = lambda r: [f(r) for f in getfieldfuncs]

    def matches(x):
        for rev in revs:
            target = getinfo(rev)
            match = True
            for n, f in enumerate(getfieldfuncs):
                if target[n] != f(x):
                    match = False
            if match:
                return True
        return False

    return subset.filter(matches)

def reverse(repo, subset, x):
    """``reverse(set)``
    Reverse order of set.
    """
    l = getset(repo, subset, x)
    l.reverse()
    return l

def roots(repo, subset, x):
    """``roots(set)``
    Changesets in set with no parent changeset in set.
    """
    s = getset(repo, spanset(repo), x).set()
    subset = baseset([r for r in s if r in subset.set()])
    cs = _children(repo, subset, s)
    return subset - cs

def secret(repo, subset, x):
    """``secret()``
    Changeset in secret phase."""
    # i18n: "secret" is a keyword
    getargs(x, 0, 0, _("secret takes no arguments"))
    pc = repo._phasecache
    return subset.filter(lambda x: pc.phase(repo, x) == phases.secret)

def sort(repo, subset, x):
    """``sort(set[, [-]key...])``
    Sort set by keys. The default sort order is ascending, specify a key
    as ``-key`` to sort in descending order.

    The keys can be:

    - ``rev`` for the revision number,
    - ``branch`` for the branch name,
    - ``desc`` for the commit message (description),
    - ``user`` for user name (``author`` can be used as an alias),
    - ``date`` for the commit date
    """
    # i18n: "sort" is a keyword
    l = getargs(x, 1, 2, _("sort requires one or two arguments"))
    keys = "rev"
    if len(l) == 2:
        # i18n: "sort" is a keyword
        keys = getstring(l[1], _("sort spec must be a string"))

    s = l[0]
    keys = keys.split()
    l = []
    def invert(s):
        return "".join(chr(255 - ord(c)) for c in s)
    revs = getset(repo, subset, s)
    if keys == ["rev"]:
   …