return ''.join(patch.diff(self._repo, rev1, rev2, match=file_filter,

                          opts=diffopts(git=True,

                                        showfunc=True,

                                        ignorews=ignore_whitespace,

                                        context=context)))

    @classmethod

    def _check_url(cls, url, repoui=None):

        """

        Function will check given url and try to verify if it's a valid

        link. Sometimes it may happened that mercurial will issue basic

        auth request that can cause whole API to hang when used from python

        or other external calls.

        On failures it'll raise urllib2.HTTPError, exception is also thrown

        when the return code is non 200

        """

        # check first if it's not an local url

        if os.path.isdir(url) or url.startswith('file:'):

            return True

        if url.startswith('ssh:'):

            # in case of invalid uri or authentication issues, sshpeer will

            # throw an exception.

            return True

        url_prefix = None

        if '+' in url[:url.find('://')]:

            url_prefix, url = url.split('+', 1)

        handlers = []

        url_obj = hg_url(url)

        test_uri, authinfo = url_obj.authinfo()

        url_obj.passwd = '*****'

        cleaned_uri = str(url_obj)

        if authinfo:

            # create a password manager

            passmgr = urllib2.HTTPPasswordMgrWithDefaultRealm()

            passmgr.add_password(*authinfo)

            handlers.extend((httpbasicauthhandler(passmgr),

                             httpdigestauthhandler(passmgr)))

        o = urllib2.build_opener(*handlers)

        o.addheaders = [('Content-Type', 'application/mercurial-0.1'),

                        ('Accept', 'application/mercurial-0.1')]

        q = {"cmd": 'between'}

        q.update({'pairs': "%s-%s" % ('0' * 40, '0' * 40)})

        qs = '?%s' % urllib.urlencode(q)

        cu = "%s%s" % (test_uri, qs)

        req = urllib2.Request(cu, None, {})

        try:

            resp = o.open(req)

            if resp.code != 200:

                raise Exception('Return Code is not 200')

        except Exception as e:

            # means it cannot be cloned

            raise urllib2.URLError("[%s] org_exc: %s" % (cleaned_uri, e))

        if not url_prefix: # skip svn+http://... (and git+... too)

            # now check if it's a proper hg repo

            try:

            except Exception as e:

                raise urllib2.URLError(

                    "url [%s] does not look like an hg repo org_exc: %s"

                    % (cleaned_uri, e))

        return True

    def _get_repo(self, create, src_url=None, update_after_clone=False):

        """

        Function will check for mercurial repository in given path and return

        a localrepo object. If there is no repository in that path it will

        raise an exception unless ``create`` parameter is set to True - in

        that case repository would be created and returned.

        If ``src_url`` is given, would try to clone repository from the

        location at given clone_point. Additionally it'll make update to

        working copy accordingly to ``update_after_clone`` flag

        """

        try:

            if src_url:

                url = safe_str(self._get_url(src_url))

                opts = {}

                if not update_after_clone:

                    opts.update({'noupdate': True})

"""

Mercurial libs compatibility

"""

import mercurial

from mercurial import demandimport

# patch demandimport, due to bug in mercurial when it always triggers demandimport.enable()

demandimport.enable = lambda *args, **kwargs: 1

from mercurial import archival, merge as hg_merge, patch, ui

from mercurial import discovery

from mercurial import localrepo

from mercurial import unionrepo

from mercurial import scmutil

from mercurial import config

from mercurial import tags as tagsmod

from mercurial.commands import clone, nullid, pull

from mercurial.context import memctx, memfilectx

from mercurial.error import RepoError, RepoLookupError, Abort

from mercurial.hgweb import hgweb_mod

from mercurial.hgweb.common import get_contact

from mercurial.match import match

from mercurial.mdiff import diffopts

from mercurial.node import hex

from mercurial.encoding import tolocal

from mercurial.discovery import findcommonoutgoing

from mercurial.hg import peer

from mercurial.util import url as hg_url

from mercurial.scmutil import revrange

from mercurial.node import nullrev

from mercurial.url import httpbasicauthhandler, httpdigestauthhandler

# Mercurial 4.5 8a0cac20a1ad introduced an extra memctx changectx argument

# - introduce an optional wrapper factory that doesn't pass it on

import inspect

if inspect.getargspec(memfilectx.__init__).args[2] != 'changectx':

    __org_memfilectx = memfilectx

    memfilectx = lambda repo, changectx, *args, **kwargs: __org_memfilectx(repo, *args, **kwargs)

# workaround for 3.3 94ac64bcf6fe and not calling largefiles reposetup correctly

localrepo.localrepository._lfstatuswriters = [lambda *msg, **opts: None]

# 3.5 7699d3212994 added the invariant that repo.lfstatus must exist before hitting overridearchive

localrepo.localrepository.lfstatus = False

# Mercurial 4.2 moved tag from localrepo to the tags module

def tag(repo, *args):

    try:

        tag_f  = tagsmod.tag

    except AttributeError: