view mercurial/fileset.py @ 26117:4dc5b51f38fe

revlog: change generaldelta delta parent heuristic The old generaldelta heuristic was "if p1 (or p2) was closer than the last full text, use it, otherwise use prev". This was problematic when a repo contained multiple branches that were very different. If commits to branch A were pushed, and the last full text was branch B, it would generate a fulltext. Then if branch B was pushed, it would generate another fulltext. The problem is that the last fulltext (and delta'ing against `prev` in general) has no correlation with the contents of the incoming revision, and therefore will always have degenerate cases. According to the blame, that algorithm was chosen to minimize the chain length. Since there is already code that protects against that (the delta-vs-fulltext code), and since it has been improved since the original generaldelta algorithm went in (2011), I believe the chain length criteria will still be preserved. The new algorithm always diffs against p1 (or p2 if it's closer), unless the resulting delta will fail the delta-vs-fulltext check, in which case we delta against prev. Some before and after stats on manifest.d size. internal large repo old heuristic - 2.0 GB new heuristic - 1.2 GB mozilla-central old heuristic - 242 MB new heuristic - 261 MB The regression in mozilla central is due to the new heuristic choosing p2r as the delta when it's closer to the tip. Switching the algorithm to always prefer p1r brings the size back down (242 MB). This is result of the way in which mozilla does merges and pushes, and the result could easily swing the other direction in other repos (depending on if they merge X into Y or Y into X), but will never be as degenerate as before. I future patch will address the regression by introducing an optional, even more aggressive delta heuristic which will knock the mozilla manifest size down dramatically.
author Durham Goode <durham@fb.com>
date Sun, 30 Aug 2015 13:58:11 -0700
parents a7527c5769bb
children fc65d63ef3b9
line wrap: on
line source

# fileset.py - file 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.

from __future__ import absolute_import

import re

from .i18n import _
from . import (
    error,
    merge,
    parser,
    util,
)

elements = {
    # token-type: binding-strength, primary, prefix, infix, suffix
    "(": (20, None, ("group", 1, ")"), ("func", 1, ")"), None),
    "-": (5, None, ("negate", 19), ("minus", 5), None),
    "not": (10, None, ("not", 10), None, None),
    "!": (10, None, ("not", 10), None, None),
    "and": (5, None, None, ("and", 5), None),
    "&": (5, None, None, ("and", 5), None),
    "or": (4, None, None, ("or", 4), None),
    "|": (4, None, None, ("or", 4), None),
    "+": (4, None, None, ("or", 4), None),
    ",": (2, None, None, ("list", 2), None),
    ")": (0, None, None, None, None),
    "symbol": (0, "symbol", None, None, None),
    "string": (0, "string", None, None, None),
    "end": (0, None, None, 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)

def parse(expr):
    p = parser.parser(elements)
    tree, pos = p.parse(tokenize(expr))
    if pos != len(expr):
        raise error.ParseError(_("invalid token"), pos)
    return tree

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 minusset(mctx, x, y):
    xl = getset(mctx, x)
    yl = set(getset(mctx, y))
    return [f for f in xl if f not in yl]

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

def modified(mctx, x):
    """``modified()``
    File that is modified according to status.
    """
    # i18n: "modified" is a keyword
    getargs(x, 0, 0, _("modified takes no arguments"))
    s = mctx.status().modified
    return [f for f in mctx.subset if f in s]

def added(mctx, x):
    """``added()``
    File that is added according to status.
    """
    # i18n: "added" is a keyword
    getargs(x, 0, 0, _("added takes no arguments"))
    s = mctx.status().added
    return [f for f in mctx.subset if f in s]

def removed(mctx, x):
    """``removed()``
    File that is removed according to status.
    """
    # i18n: "removed" is a keyword
    getargs(x, 0, 0, _("removed takes no arguments"))
    s = mctx.status().removed
    return [f for f in mctx.subset if f in s]

def deleted(mctx, x):
    """``deleted()``
    File that is deleted according to status.
    """
    # i18n: "deleted" is a keyword
    getargs(x, 0, 0, _("deleted takes no arguments"))
    s = mctx.status().deleted
    return [f for f in mctx.subset if f in s]

def unknown(mctx, x):
    """``unknown()``
    File that is unknown according to status. These files will only be
    considered if this predicate is used.
    """
    # i18n: "unknown" is a keyword
    getargs(x, 0, 0, _("unknown takes no arguments"))
    s = mctx.status().unknown
    return [f for f in mctx.subset if f in s]

def ignored(mctx, x):
    """``ignored()``
    File that is ignored according to status. These files will only be
    considered if this predicate is used.
    """
    # i18n: "ignored" is a keyword
    getargs(x, 0, 0, _("ignored takes no arguments"))
    s = mctx.status().ignored
    return [f for f in mctx.subset if f in s]

def clean(mctx, x):
    """``clean()``
    File that is clean according to status.
    """
    # i18n: "clean" is a keyword
    getargs(x, 0, 0, _("clean takes no arguments"))
    s = mctx.status().clean
    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)

    keep = lambda fn: getattr(fn, '__doc__', None) is not None

    syms = [s for (s, fn) in symbols.items() if keep(fn)]
    raise error.UnknownIdentifier(a[1], syms)

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):
    """``binary()``
    File that appears to be binary (contains NUL bytes).
    """
    # i18n: "binary" is a keyword
    getargs(x, 0, 0, _("binary takes no arguments"))
    return [f for f in mctx.existing() if util.binary(mctx.ctx[f].data())]

def exec_(mctx, x):
    """``exec()``
    File that is marked as executable.
    """
    # i18n: "exec" is a keyword
    getargs(x, 0, 0, _("exec takes no arguments"))
    return [f for f in mctx.existing() if mctx.ctx.flags(f) == 'x']

def symlink(mctx, x):
    """``symlink()``
    File that is marked as a symlink.
    """
    # i18n: "symlink" is a keyword
    getargs(x, 0, 0, _("symlink takes no arguments"))
    return [f for f in mctx.existing() if mctx.ctx.flags(f) == 'l']

def resolved(mctx, x):
    """``resolved()``
    File that is marked resolved according to the resolve state.
    """
    # i18n: "resolved" is a keyword
    getargs(x, 0, 0, _("resolved takes no arguments"))
    if mctx.ctx.rev() is not None:
        return []
    ms = merge.mergestate(mctx.ctx.repo())
    return [f for f in mctx.subset if f in ms and ms[f] == 'r']

def unresolved(mctx, x):
    """``unresolved()``
    File that is marked unresolved according to the resolve state.
    """
    # i18n: "unresolved" is a keyword
    getargs(x, 0, 0, _("unresolved takes no arguments"))
    if mctx.ctx.rev() is not None:
        return []
    ms = merge.mergestate(mctx.ctx.repo())
    return [f for f in mctx.subset if f in ms and ms[f] == 'u']

def hgignore(mctx, x):
    """``hgignore()``
    File that matches the active .hgignore pattern.
    """
    # i18n: "hgignore" is a keyword
    getargs(x, 0, 0, _("hgignore takes no arguments"))
    ignore = mctx.ctx.repo().dirstate._ignore
    return [f for f in mctx.subset if ignore(f)]

def portable(mctx, x):
    """``portable()``
    File that has a portable name. (This doesn't include filenames with case
    collisions.)
    """
    # i18n: "portable" is a keyword
    getargs(x, 0, 0, _("portable takes no arguments"))
    checkwinfilename = util.checkwinfilename
    return [f for f in mctx.subset if checkwinfilename(f) is None]

def grep(mctx, x):
    """``grep(regex)``
    File contains the given regular expression.
    """
    try:
        # i18n: "grep" is a keyword
        r = re.compile(getstring(x, _("grep requires a pattern")))
    except re.error as e:
        raise error.ParseError(_('invalid match pattern: %s') % e)
    return [f for f in mctx.existing() if r.search(mctx.ctx[f].data())]

def _sizetomax(s):
    try:
        s = s.strip().lower()
        for k, v in util._sizeunits:
            if s.endswith(k):
                # max(4k) = 5k - 1, max(4.5k) = 4.6k - 1
                n = s[:-len(k)]
                inc = 1.0
                if "." in n:
                    inc /= 10 ** len(n.split(".")[1])
                return int((float(n) + inc) * v) - 1
        # no extension, this is a precise value
        return int(s)
    except ValueError:
        raise error.ParseError(_("couldn't parse size: %s") % s)

def size(mctx, x):
    """``size(expression)``
    File size matches the given expression. Examples:

    - 1k (files from 1024 to 2047 bytes)
    - < 20k (files less than 20480 bytes)
    - >= .5MB (files at least 524288 bytes)
    - 4k - 1MB (files from 4096 bytes to 1048576 bytes)
    """

    # i18n: "size" is a keyword
    expr = getstring(x, _("size requires an expression")).strip()
    if '-' in expr: # do we have a range?
        a, b = expr.split('-', 1)
        a = util.sizetoint(a)
        b = util.sizetoint(b)
        m = lambda x: x >= a and x <= b
    elif expr.startswith("<="):
        a = util.sizetoint(expr[2:])
        m = lambda x: x <= a
    elif expr.startswith("<"):
        a = util.sizetoint(expr[1:])
        m = lambda x: x < a
    elif expr.startswith(">="):
        a = util.sizetoint(expr[2:])
        m = lambda x: x >= a
    elif expr.startswith(">"):
        a = util.sizetoint(expr[1:])
        m = lambda x: x > a
    elif expr[0].isdigit or expr[0] == '.':
        a = util.sizetoint(expr)
        b = _sizetomax(expr)
        m = lambda x: x >= a and x <= b
    else:
        raise error.ParseError(_("couldn't parse size: %s") % expr)

    return [f for f in mctx.existing() if m(mctx.ctx[f].size())]

def encoding(mctx, x):
    """``encoding(name)``
    File can be successfully decoded with the given character
    encoding. May not be useful for encodings other than ASCII and
    UTF-8.
    """

    # i18n: "encoding" is a keyword
    enc = getstring(x, _("encoding requires an encoding name"))

    s = []
    for f in mctx.existing():
        d = mctx.ctx[f].data()
        try:
            d.decode(enc)
        except LookupError:
            raise util.Abort(_("unknown encoding '%s'") % enc)
        except UnicodeDecodeError:
            continue
        s.append(f)

    return s

def eol(mctx, x):
    """``eol(style)``
    File contains newlines of the given style (dos, unix, mac). Binary
    files are excluded, files with mixed line endings match multiple
    styles.
    """

    # i18n: "encoding" is a keyword
    enc = getstring(x, _("encoding requires an encoding name"))

    s = []
    for f in mctx.existing():
        d = mctx.ctx[f].data()
        if util.binary(d):
            continue
        if (enc == 'dos' or enc == 'win') and '\r\n' in d:
            s.append(f)
        elif enc == 'unix' and re.search('(?<!\r)\n', d):
            s.append(f)
        elif enc == 'mac' and re.search('\r(?!\n)', d):
            s.append(f)
    return s

def copied(mctx, x):
    """``copied()``
    File that is recorded as being copied.
    """
    # i18n: "copied" is a keyword
    getargs(x, 0, 0, _("copied takes no arguments"))
    s = []
    for f in mctx.subset:
        p = mctx.ctx[f].parents()
        if p and p[0].path() != f:
            s.append(f)
    return s

def subrepo(mctx, x):
    """``subrepo([pattern])``
    Subrepositories whose paths match the given pattern.
    """
    # i18n: "subrepo" is a keyword
    getargs(x, 0, 1, _("subrepo takes at most one argument"))
    ctx = mctx.ctx
    sstate = sorted(ctx.substate)
    if x:
        # i18n: "subrepo" is a keyword
        pat = getstring(x, _("subrepo requires a pattern or no arguments"))

        from . import match as matchmod # avoid circular import issues
        fast = not matchmod.patkind(pat)
        if fast:
            def m(s):
                return (s == pat)
        else:
            m = matchmod.match(ctx.repo().root, '', [pat], ctx=ctx)
        return [sub for sub in sstate if m(sub)]
    else:
        return [sub for sub in sstate]

symbols = {
    'added': added,
    'binary': binary,
    'clean': clean,
    'copied': copied,
    'deleted': deleted,
    'encoding': encoding,
    'eol': eol,
    'exec': exec_,
    'grep': grep,
    'ignored': ignored,
    'hgignore': hgignore,
    'modified': modified,
    'portable': portable,
    'removed': removed,
    'resolved': resolved,
    'size': size,
    'symlink': symlink,
    'unknown': unknown,
    'unresolved': unresolved,
    'subrepo': subrepo,
}

methods = {
    'string': stringset,
    'symbol': stringset,
    'and': andset,
    'or': orset,
    'minus': minusset,
    '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 existing(self):
        if self._status is not None:
            removed = set(self._status[3])
            unknown = set(self._status[4] + self._status[5])
        else:
            removed = set()
            unknown = set()
        return (f for f in self.subset
                if (f in self.ctx and f not in removed) or f in unknown)
    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

# filesets using matchctx.existing()
_existingcallers = [
    'binary',
    'exec',
    'grep',
    'size',
    'symlink',
]

def getfileset(ctx, expr):
    tree = parse(expr)

    # do we need status info?
    if (_intree(['modified', 'added', 'removed', 'deleted',
                 'unknown', 'ignored', 'clean'], tree) or
        # Using matchctx.existing() on a workingctx requires us to check
        # for deleted files.
        (ctx.rev() is None and _intree(_existingcallers, 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 = list(ctx.walk(ctx.match([])))

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

def prettyformat(tree):
    return parser.prettyformat(tree, ('string', 'symbol'))

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