hgext/interhg.py

convert/svn: do not try converting empty head revisions (issue3347)

Subversion conversion works by picking trunk and branches heads, computing a
revision graph from them and converting the selected commits. By design we fail
to convert empty revisions so we have to be careful when discovering the
revision graph. In this particular issue, the source svn repository was a
partial mirror made by svnsync. The funny part is svnsync preserves all
revisions including empty ones. Also, we trusted ra.stat(path,
stop).created_rev to give us the latest revision with changes in path history
up to stop. This assumption broke at least when path is '', that is the
repository root, which always returned 'stop' revision despited being empty.

The workaround is to first trust ra.stat() but if the returned revision appear
empty, search the whole path history from stop to r1 until some changes are
found.

# interhg.py - interhg
#
# Copyright 2007 OHASHI Hideya <[e-mail]>
#
# Contributor(s):
#   Edward Lee <[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.

'''expand expressions into changelog and summaries

This extension allows the use of a special syntax in summaries, which
will be automatically expanded into links or any other arbitrary
expression, much like InterWiki does.

A few example patterns (link to bug tracking, etc.) that may be used
in your hgrc::

  [interhg]
  issues = s!issue(\\d+)!<a href="http://bts/issue\\1">issue\\1</a>!
  bugzilla = s!((?:bug|b=|(?=#?\\d{4,}))(?:\\s*#?)(\\d+))!<a..=\\2">\\1</a>!i
  boldify = s!(^|\\s)#(\\d+)\\b! <b>#\\2</b>!
'''

import re
from mercurial.hgweb import hgweb_mod
from mercurial import templatefilters, extensions
from mercurial.i18n import _

interhg_table = []

def uisetup(ui):
    orig_escape = templatefilters.filters["escape"]

    def interhg_escape(x):
        escstr = orig_escape(x)
        for regexp, format in interhg_table:
            escstr = regexp.sub(format, escstr)
        return escstr

    templatefilters.filters["escape"] = interhg_escape

def interhg_refresh(orig, self, *args, **kwargs):
    interhg_table[:] = []
    for key, pattern in self.repo.ui.configitems('interhg'):
        # grab the delimiter from the character after the "s"
        unesc = pattern[1]
        delim = re.escape(unesc)

        # identify portions of the pattern, taking care to avoid escaped
        # delimiters. the replace format and flags are optional, but delimiters
        # are required.
        match = re.match(r'^s%s(.+)(?:(?<=\\\\)|(?<!\\))%s(.*)%s([ilmsux])*$'
                         % (delim, delim, delim), pattern)
        if not match:
            self.repo.ui.warn(_("interhg: invalid pattern for %s: %s\n")
                              % (key, pattern))
            continue

        # we need to unescape the delimiter for regexp and format
        delim_re = re.compile(r'(?<!\\)\\%s' % delim)
        regexp = delim_re.sub(unesc, match.group(1))
        format = delim_re.sub(unesc, match.group(2))

        # the pattern allows for 6 regexp flags, so set them if necessary
        flagin = match.group(3)
        flags = 0
        if flagin:
            for flag in flagin.upper():
                flags |= re.__dict__[flag]

        try:
            regexp = re.compile(regexp, flags)
            interhg_table.append((regexp, format))
        except re.error:
            self.repo.ui.warn(_("interhg: invalid regexp for %s: %s\n")
                              % (key, regexp))
    return orig(self, *args, **kwargs)

extensions.wrapfunction(hgweb_mod.hgweb, 'refresh', interhg_refresh)