mercurial/fileset.py

fileset: prescan parse tree to optimize status usage

We only call status if needed to avoid walking the working directory
or comparing manifests.

Similarly, we scan for whether unknown or ignored files are mentioned
so we can include them.

# fileset.py - file set queries for mercurial
#
# Copyright 2010 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.

import parser, error, util
from i18n import _

elements = {
    "(": (20, ("group", 1, ")"), ("func", 1, ")")),
    "-": (5, ("negate", 19), ("minus", 5)),
    "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'])

globchars = ".*{}[]?/\\"

def tokenize(program):
    pos, l = 0, len(program)
    while pos < l:
        c = program[pos]
        if c.isspace(): # skip inter-token whitespace
            pass
        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)
        elif c.isalnum() or c in globchars or ord(c) > 127:
            # gather up a symbol/keyword
            s = pos
            pos += 1
            while pos < l: # find end of symbol
                d = program[pos]
                if not (d.isalnum() or d in globchars or ord(d) > 127):
                    break
                pos += 1
            sym = program[s:pos]
            if sym in keywords: # operator keywords
                yield (sym, None, s)
            else:
                yield ('symbol', sym, s)
            pos -= 1
        else:
            raise error.ParseError(_("syntax error"), pos)
        pos += 1
    yield ('end', None, pos)

parse = parser.parser(tokenize, elements).parse

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

def getset(mctx, x):
    if not x:
        raise error.ParseError(_("missing argument"))
    return methods[x[0]](mctx, *x[1:])

def stringset(mctx, x):
    m = mctx.matcher([x])
    return [f for f in mctx.subset if m(f)]

def andset(mctx, x, y):
    return getset(mctx.narrow(getset(mctx, x)), y)

def orset(mctx, x, y):
    # needs optimizing
    xl = getset(mctx, x)
    yl = getset(mctx, y)
    return xl + [f for f in yl if f not in xl]

def notset(mctx, x):
    s = set(getset(mctx, x))
    return [r for r in mctx.subset if r not in s]

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

def modified(mctx, x):
    getargs(x, 0, 0, _("modified takes no arguments"))
    s = mctx.status()[0]
    return [f for f in mctx.subset if f in s]

def added(mctx, x):
    getargs(x, 0, 0, _("added takes no arguments"))
    s = mctx.status()[1]
    return [f for f in mctx.subset if f in s]

def removed(mctx, x):
    getargs(x, 0, 0, _("removed takes no arguments"))
    s = mctx.status()[2]
    return [f for f in mctx.subset if f in s]

def deleted(mctx, x):
    getargs(x, 0, 0, _("deleted takes no arguments"))
    s = mctx.status()[3]
    return [f for f in mctx.subset if f in s]

def unknown(mctx, x):
    getargs(x, 0, 0, _("unknown takes no arguments"))
    s = mctx.status()[4]
    return [f for f in mctx.subset if f in s]

def ignored(mctx, x):
    getargs(x, 0, 0, _("ignored takes no arguments"))
    s = mctx.status()[5]
    return [f for f in mctx.subset if f in s]

def clean(mctx, x):
    getargs(x, 0, 0, _("clean takes no arguments"))
    s = mctx.status()[6]
    return [f for f in mctx.subset if f in s]

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

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 len(l) > max:
        raise error.ParseError(err)
    return l

def binary(mctx, x):
    getargs(x, 0, 0, _("binary takes no arguments"))
    return [f for f in mctx.subset if util.binary(mctx.ctx[f].data())]

def exec_(mctx, x):
    getargs(x, 0, 0, _("exec takes no arguments"))
    return [f for f in mctx.subset if mctx.ctx.flags(f) == 'x']

def symlink(mctx, x):
    getargs(x, 0, 0, _("symlink takes no arguments"))
    return [f for f in mctx.subset if mctx.ctx.flags(f) == 'l']

symbols = {
    'added': added,
    'binary': binary,
    'clean': clean,
    'deleted': deleted,
    'exec': exec_,
    'ignored': ignored,
    'modified': modified,
    'removed': removed,
    'symlink': symlink,
    'unknown': unknown,
}

methods = {
    'string': stringset,
    'symbol': stringset,
    'and': andset,
    'or': orset,
    'list': listset,
    'group': getset,
    'not': notset,
    'func': func,
}

class matchctx(object):
    def __init__(self, ctx, subset=None, status=None):
        self.ctx = ctx
        self.subset = subset
        self._status = status
    def status(self):
        return self._status
    def matcher(self, patterns):
        return self.ctx.match(patterns)
    def filter(self, files):
        return [f for f in files if f in self.subset]
    def narrow(self, files):
        return matchctx(self.ctx, self.filter(files), self._status)

def _intree(funcs, tree):
    if isinstance(tree, tuple):
        if tree[0] == 'func' and tree[1][0] == 'symbol':
            if tree[1][1] in funcs:
                return True
        for s in tree[1:]:
            if _intree(funcs, s):
                return True
    return False

def getfileset(ctx, expr):
    tree, pos = parse(expr)
    if (pos != len(expr)):
        raise error.ParseError("invalid token", pos)

    # do we need status info?
    if _intree(['modified', 'added', 'removed', 'deleted',
                'unknown', 'ignored', 'clean'], tree):
        unknown = _intree(['unknown'], tree)
        ignored = _intree(['ignored'], tree)

        r = ctx._repo
        status = r.status(ctx.p1(), ctx,
                          unknown=unknown, ignored=ignored, clean=True)
        subset = []
        for c in status:
            subset.extend(c)
    else:
        status = None
        subset = ctx.walk(ctx.match([]))

    return getset(matchctx(ctx, subset, status), tree)