controllers: don’t pass start=0 to BaseRepository.get_changesets()

MercurialRepository.get_changesets() can fail if passing start=0 if the
revision 0 is not in self.revisions. That can happen if revision 0 is not in
the visible subset of the revisions in the repository. Before Kallithea
changeset 7c43e15fb8bc7a73f17f577e59a4698589b6809d, it was working by chance
because start=0 was treated like start=None in the relevant places
(GitRepository.get_changesets still does that).

The intention of passing start=0 was seemingly to not limit the start.
Therefore passing start=None (or nothing, as it’s the default value) should be
correct.

I got the following traceback before this change:

Traceback (most recent call last):
  File "~/vcs/kallithea/kallithea/controllers/changelog.py", line 117, in index
    collection = c.db_repo_scm_instance.get_changesets(start=0, end=revision,
  File "~/vcs/kallithea/kallithea/lib/vcs/backends/hg/repository.py", line 529, in get_changesets
    start_pos = None if start is None else self.revisions.index(start_raw_id)
ValueError: '4257f758b3eaacaebb6956d1aefc019afab956b8' is not in list

kallithea/controllers/changelog.py

@@ -1,157 +1,157 b''
 # -*- coding: utf-8 -*-
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 """
 kallithea.controllers.changelog
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 changelog controller for Kallithea
 
 This file was forked by the Kallithea project in July 2014.
 Original author and date, and relevant copyright and licensing information is below:
 :created_on: Apr 21, 2010
 :author: marcink
 :copyright: (c) 2013 RhodeCode GmbH, and others.
 :license: GPLv3, see LICENSE.md for more details.
 """
 
 import logging
 import traceback
 
 from tg import request, session
 from tg import tmpl_context as c
 from tg.i18n import ugettext as _
 from webob.exc import HTTPBadRequest, HTTPFound, HTTPNotFound
 
 from kallithea.controllers import base
 from kallithea.lib import webutils
 from kallithea.lib.auth import HasRepoPermissionLevelDecorator, LoginRequired
 from kallithea.lib.graphmod import graph_data
 from kallithea.lib.page import Page
 from kallithea.lib.utils2 import safe_int
 from kallithea.lib.vcs.exceptions import ChangesetDoesNotExistError, ChangesetError, EmptyRepositoryError, NodeDoesNotExistError, RepositoryError
 from kallithea.lib.webutils import url
 
 
 log = logging.getLogger(__name__)
 
 
 class ChangelogController(base.BaseRepoController):
 
     def _before(self, *args, **kwargs):
         super(ChangelogController, self)._before(*args, **kwargs)
         c.affected_files_cut_off = 60
 
     @staticmethod
     def __get_cs(rev, repo):
         """
         Safe way to get changeset. If error occur fail with error message.
 
         :param rev: revision to fetch
         :param repo: repo instance
         """
 
         try:
             return c.db_repo_scm_instance.get_changeset(rev)
         except EmptyRepositoryError as e:
             webutils.flash(_('There are no changesets yet'), category='error')
         except RepositoryError as e:
             log.error(traceback.format_exc())
             webutils.flash(e, category='error')
         raise HTTPBadRequest()
 
     @LoginRequired(allow_default_user=True)
     @HasRepoPermissionLevelDecorator('read')
     def index(self, repo_name, revision=None, f_path=None):
         limit = 2000
         default = 100
         if request.GET.get('size'):
             c.size = max(min(safe_int(request.GET.get('size')), limit), 1)
             session['changelog_size'] = c.size
             session.save()
         else:
             c.size = int(session.get('changelog_size', default))
         # min size must be 1
         c.size = max(c.size, 1)
         p = safe_int(request.GET.get('page'), 1)
         branch_name = request.GET.get('branch', None)
         if (branch_name and
             branch_name not in c.db_repo_scm_instance.branches and
             branch_name not in c.db_repo_scm_instance.closed_branches and
             not revision
         ):
             raise HTTPFound(location=url('changelog_file_home', repo_name=c.repo_name,
                                     revision=branch_name, f_path=f_path or ''))
 
         if revision == 'tip':
             revision = None
 
         c.changelog_for_path = f_path
         try:
 
             if f_path:
                 log.debug('generating changelog for path %s', f_path)
                 # get the history for the file !
                 tip_cs = c.db_repo_scm_instance.get_changeset()
                 try:
                     collection = tip_cs.get_file_history(f_path)
                 except (NodeDoesNotExistError, ChangesetError):
                     # this node is not present at tip !
                     try:
                         cs = self.__get_cs(revision, repo_name)
                         collection = cs.get_file_history(f_path)
                     except RepositoryError as e:
                         webutils.flash(e, category='warning')
                         raise HTTPFound(location=webutils.url('changelog_home', repo_name=repo_name))
             else:
-                collection = c.db_repo_scm_instance.get_changesets(start=0, end=revision,
+                collection = c.db_repo_scm_instance.get_changesets(end=revision,
                                                         branch_name=branch_name, reverse=True)
             c.total_cs = len(collection)
 
             c.cs_pagination = Page(collection, page=p, item_count=c.total_cs, items_per_page=c.size,
                                    branch=branch_name)
 
             page_revisions = [x.raw_id for x in c.cs_pagination]
             c.cs_comments = c.db_repo.get_comments(page_revisions)
             c.cs_statuses = c.db_repo.statuses(page_revisions)
         except EmptyRepositoryError as e:
             webutils.flash(e, category='warning')
             raise HTTPFound(location=url('summary_home', repo_name=c.repo_name))
         except (RepositoryError, ChangesetDoesNotExistError, Exception) as e:
             log.error(traceback.format_exc())
             webutils.flash(e, category='error')
             raise HTTPFound(location=url('changelog_home', repo_name=c.repo_name))
 
         c.branch_name = branch_name
         c.branch_filters = [('', _('None'))] + \
             [(k, k) for k in c.db_repo_scm_instance.branches]
         if c.db_repo_scm_instance.closed_branches:
             prefix = _('(closed)') + ' '
             c.branch_filters += [('-', '-')] + \
                 [(k, prefix + k) for k in c.db_repo_scm_instance.closed_branches]
         revs = []
         if not f_path:
             revs = [x.revision for x in c.cs_pagination]
         c.jsdata = graph_data(c.db_repo_scm_instance, revs)
 
         c.revision = revision # requested revision ref
         c.first_revision = c.cs_pagination[0] # pagination is never empty here!
         return base.render('changelog/changelog.html')
 
     @LoginRequired(allow_default_user=True)
     @HasRepoPermissionLevelDecorator('read')
     def changelog_details(self, cs):
         if request.environ.get('HTTP_X_PARTIAL_XHR'):
             c.cs = c.db_repo_scm_instance.get_changeset(cs)
             return base.render('changelog/changelog_details.html')
         raise HTTPNotFound()