revision=c.changeset_1.revision,

                                                   repo=c.db_repo_scm_instance)

                    node1 = FileNode(f_path, '', changeset=c.changeset_1)

            else:

                c.changeset_1 = EmptyChangeset(repo=c.db_repo_scm_instance)

                node1 = FileNode(f_path, '', changeset=c.changeset_1)

            if diff2 not in ['', None, 'None', '0' * 12, '0' * 40]:

                c.changeset_2 = c.db_repo_scm_instance.get_changeset(diff2)

                try:

                    node2 = c.changeset_2.get_node(f_path)

                    if node2.is_dir():

                        raise NodeError('%s path is a %s not a file'

                                        % (node2, type(node2)))

                except NodeDoesNotExistError:

                    c.changeset_2 = EmptyChangeset(cs=diff2,

                                                   revision=c.changeset_2.revision,

                                                   repo=c.db_repo_scm_instance)

                    node2 = FileNode(f_path, '', changeset=c.changeset_2)

            else:

                c.changeset_2 = EmptyChangeset(repo=c.db_repo_scm_instance)

                node2 = FileNode(f_path, '', changeset=c.changeset_2)

        except (RepositoryError, NodeError):

            log.error(traceback.format_exc())

            raise HTTPFound(location=url('files_home', repo_name=c.repo_name,

                                f_path=f_path))

        if c.action == 'download':

            raw_diff = diffs.get_gitdiff(node1, node2,

                                      ignore_whitespace=ignore_whitespace_diff,

                                      context=diff_context_size)

            diff_name = '%s_vs_%s.diff' % (diff1, diff2)

            response.content_type = 'text/plain'

            response.content_disposition = (

                'attachment; filename=%s' % diff_name

            )

            return raw_diff

        elif c.action == 'raw':

            raw_diff = diffs.get_gitdiff(node1, node2,

                                      ignore_whitespace=ignore_whitespace_diff,

                                      context=diff_context_size)

            response.content_type = 'text/plain'

            return raw_diff

        else:

            fid = h.FID(diff2, node2.path)

            diff_limit = None if fulldiff else self.cut_off_limit

                                         filenode_new=node2,

                                         diff_limit=diff_limit,

                                         ignore_whitespace=ignore_whitespace_diff,

                                         line_context=diff_context_size)

            c.file_diff_data = [(fid, fid, op, a_path, node2.path, diff, st)]

            return base.render('files/file_diff.html')

    @LoginRequired(allow_default_user=True)

    @HasRepoPermissionLevelDecorator('read')

    def diff_2way(self, repo_name, f_path):

        diff1 = request.GET.get('diff1', '')

        diff2 = request.GET.get('diff2', '')

        try:

            if diff1 not in ['', None, 'None', '0' * 12, '0' * 40]:

                c.changeset_1 = c.db_repo_scm_instance.get_changeset(diff1)

                try:

                    node1 = c.changeset_1.get_node(f_path)

                    if node1.is_dir():

                        raise NodeError('%s path is a %s not a file'

                                        % (node1, type(node1)))

                except NodeDoesNotExistError:

                    c.changeset_1 = EmptyChangeset(cs=diff1,

                                                   revision=c.changeset_1.revision,

                                                   repo=c.db_repo_scm_instance)

                    node1 = FileNode(f_path, '', changeset=c.changeset_1)

            else:

                c.changeset_1 = EmptyChangeset(repo=c.db_repo_scm_instance)

                node1 = FileNode(f_path, '', changeset=c.changeset_1)

            if diff2 not in ['', None, 'None', '0' * 12, '0' * 40]:

                c.changeset_2 = c.db_repo_scm_instance.get_changeset(diff2)

                try:

                    node2 = c.changeset_2.get_node(f_path)

                    if node2.is_dir():

                        raise NodeError('%s path is a %s not a file'

                                        % (node2, type(node2)))

                except NodeDoesNotExistError:

                    c.changeset_2 = EmptyChangeset(cs=diff2,

                                                   revision=c.changeset_2.revision,

                                                   repo=c.db_repo_scm_instance)

                    node2 = FileNode(f_path, '', changeset=c.changeset_2)

            else:

                c.changeset_2 = EmptyChangeset(repo=c.db_repo_scm_instance)

                node2 = FileNode(f_path, '', changeset=c.changeset_2)

        except ChangesetDoesNotExistError as e:

            msg = _('Such revision does not exist for this repository')

            webutils.flash(msg, category='error')

            raise HTTPNotFound()

                        'label': change['new_lineno'],

                        'url': '#%s' % anchor_new,

                    })

                    _html.append('''</td>\n''')

                else:

                    ###########################################################

                    # NO LINE NUMBER

                    ###########################################################

                    anchor = "%(filename)s_%(count_no_lineno)s" % {

                        'filename': _safe_id(file_info['filename']),

                        'count_no_lineno': count_no_lineno,

                    }

                    count_no_lineno += 1

                    _html.append('''\t<td id="%(anchor)s" class="%(olc)s" colspan="2">''' % {

                        'anchor': anchor,

                        'olc': no_lineno_class,

                    })

                    _html.append('''</td>\n''')

                ###########################################################

                # CODE

                ###########################################################

                _html.append('''\t<td class="%(cc)s">''' % {

                    'cc': code_class,

                })

                _html.append('''\n\t\t<div class="add-bubble"><div>&nbsp;</div></div><pre>%(code)s</pre>\n''' % {

                    'code': change['line']

                })

                _html.append('''\t</td>''')

                _html.append('''\n</tr>\n''')

    _html.append('''</table>''')

    if _html_empty:

        return None

    return ''.join(_html)

def wrap_to_table(html):

    """Given a string with html, return it wrapped in a table, similar to what

    as_html returns."""

    return '''\

              <table class="code-difftable">

                <tr class="line">

                <td class="lineno new"></td>

                <td class="code"><pre>%s</pre></td>

                </tr>

              </table>''' % html

                ignore_whitespace=True, line_context=3):

    """

    Checks for diff_limit and presents a message if the diff is too big.

    """

    if filenode_old is None:

        filenode_old = FileNode(filenode_new.path, '', EmptyChangeset())

    op = None

    a_path = filenode_old.path # default, might be overriden by actual rename in diff

    if filenode_old.is_binary or filenode_new.is_binary:

        html_diff = wrap_to_table(_('Binary file'))

        stats = (0, 0)

    elif diff_limit != -1 and (

            diff_limit is None or

            (filenode_old.size < diff_limit and filenode_new.size < diff_limit)):

        raw_diff = get_gitdiff(filenode_old, filenode_new,

                                ignore_whitespace=ignore_whitespace,

                                context=line_context)

        diff_processor = DiffProcessor(raw_diff)

        if diff_processor.parsed: # there should be exactly one element, for the specified file

            f = diff_processor.parsed[0]

            op = f['operation']

            a_path = f['old_filename']

        html_diff = as_html(parsed_lines=diff_processor.parsed)

        stats = diff_processor.stat()

    else:

        html_diff = wrap_to_table(_('Changeset was too big and was cut off, use '

                               'diff menu to display this diff'))

        stats = (0, 0)

    if not html_diff:

        submodules = [o for o in [filenode_new, filenode_old] if isinstance(o, SubModuleNode)]

        if submodules:

            html_diff = wrap_to_table(webutils.escape('Submodule %r' % submodules[0]))

        else:

            html_diff = wrap_to_table(_('No changes detected'))

    cs1 = filenode_old.changeset.raw_id

    cs2 = filenode_new.changeset.raw_id

    return cs1, cs2, a_path, html_diff, stats, op

def get_gitdiff(filenode_old, filenode_new, ignore_whitespace=True, context=3):

    """

    Returns git style diff between given ``filenode_old`` and ``filenode_new``.