mercurial/ignore.py

mdiff: compare content of binary files directly

A plain Python string comparison stops when the first mismatch is
found, whereas the call to md5 would need to compute the hash over the
entire string and only then do the comparison.

# ignore.py - ignored file handling for mercurial
#
# Copyright 2007 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

from i18n import _
import util, re

_commentre = None

def _parselines(fp):
    for line in fp:
        if "#" in line:
            global _commentre
            if not _commentre:
                _commentre = re.compile(r'((^|[^\\])(\\\\)*)#.*')
            # remove comments prefixed by an even number of escapes
            line = _commentre.sub(r'\1', line)
            # fixup properly escaped comments that survived the above
            line = line.replace("\\#", "#")
        line = line.rstrip()
        if line:
            yield line

def ignore(root, files, warn):
    '''return the contents of .hgignore files as a list of patterns.

    the files parsed for patterns include:
    .hgignore in the repository root
    any additional files specified in the [ui] section of ~/.hgrc

    trailing white space is dropped.
    the escape character is backslash.
    comments start with #.
    empty lines are skipped.

    lines can be of the following formats:

    syntax: regexp # defaults following lines to non-rooted regexps
    syntax: glob   # defaults following lines to non-rooted globs
    re:pattern     # non-rooted regular expression
    glob:pattern   # non-rooted glob
    pattern        # pattern of the current default type'''

    syntaxes = {'re': 'relre:', 'regexp': 'relre:', 'glob': 'relglob:'}
    pats = {}
    for f in files:
        try:
            pats[f] = []
            fp = open(f)
            syntax = 'relre:'
            for line in _parselines(fp):
                if line.startswith('syntax:'):
                    s = line[7:].strip()
                    try:
                        syntax = syntaxes[s]
                    except KeyError:
                        warn(_("%s: ignoring invalid syntax '%s'\n") % (f, s))
                    continue
                pat = syntax + line
                for s, rels in syntaxes.items():
                    if line.startswith(rels):
                        pat = line
                        break
                    elif line.startswith(s+':'):
                        pat = rels + line[len(s)+1:]
                        break
                pats[f].append(pat)
        except IOError, inst:
            if f != files[0]:
                warn(_("skipping unreadable ignore file '%s': %s\n") %
                     (f, inst.strerror))

    allpats = []
    [allpats.extend(patlist) for patlist in pats.values()]
    if not allpats:
        return util.never

    try:
        files, ignorefunc, anypats = (
            util.matcher(root, inc=allpats, src='.hgignore'))
    except util.Abort:
        # Re-raise an exception where the src is the right file
        for f, patlist in pats.items():
            files, ignorefunc, anypats = (
                util.matcher(root, inc=patlist, src=f))

    return ignorefunc