view mercurial/ignore.py @ 5042:f191bc3916f7

merge: do early copy to deal with issue636

Without copies/renames, merges source names are 1:1 with their
targets. Copies and renames introduce the possibility that there will
be two merges with the same input but different output. By doing the
copy to the destination name before the merge, the actual merge
becomes 1:1 again, and no source is the input to two different merges.

- add a preliminary scan to applyupdates to do copies
- for the merge action, pass the old name (for finding ancestors) and
  the new name (for input to the merge) to filemerge
- eliminate the old post-merge copy
- lookup file contents from new name in filemerge
- pass new name to external merge helper
- report merge failure at new name
- add a test

# 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

def _parselines(fp):
    for line in fp:
        if not line.endswith('\n'):
            line += '\n'
        escape = False
        for i in xrange(len(line)):
            if escape: escape = False
            elif line[i] == '\\': escape = True
            elif line[i] == '#': break
        line = line[:i].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


    '''default match function used by dirstate and
    localrepository.  this honours the repository .hgignore file
    and any other files specified in the [ui] section of .hgrc.'''