pr: Refactor PR update error message handling.

rhodecode/controllers/pullrequests.py

@@ -1,890 +1,887 b''
 # -*- coding: utf-8 -*-
 
 # Copyright (C) 2012-2016  RhodeCode GmbH
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU Affero General Public License, version 3
 # (only), as published by the Free Software Foundation.
 #
 # 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 Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 # This program is dual-licensed. If you wish to learn more about the
 # RhodeCode Enterprise Edition, including its added features, Support services,
 # and proprietary license terms, please see https://rhodecode.com/licenses/
 
 """
 pull requests controller for rhodecode for initializing pull requests
 """
 
 import peppercorn
 import formencode
 import logging
 
 from webob.exc import HTTPNotFound, HTTPForbidden, HTTPBadRequest
 from pylons import request, tmpl_context as c, url
 from pylons.controllers.util import redirect
 from pylons.i18n.translation import _
 from pyramid.threadlocal import get_current_registry
 from sqlalchemy.sql import func
 from sqlalchemy.sql.expression import or_
 
 from rhodecode import events
 from rhodecode.lib import auth, diffs, helpers as h
 from rhodecode.lib.ext_json import json
 from rhodecode.lib.base import (
     BaseRepoController, render, vcs_operation_context)
 from rhodecode.lib.auth import (
     LoginRequired, HasRepoPermissionAnyDecorator, NotAnonymous,
     HasAcceptedRepoType, XHRRequired)
 from rhodecode.lib.channelstream import channelstream_request
 from rhodecode.lib.utils import jsonify
 from rhodecode.lib.utils2 import safe_int, safe_str, str2bool, safe_unicode
 from rhodecode.lib.vcs.backends.base import EmptyCommit, UpdateFailureReason
 from rhodecode.lib.vcs.exceptions import (
     EmptyRepositoryError, CommitDoesNotExistError, RepositoryRequirementError)
 from rhodecode.lib.diffs import LimitedDiffContainer
 from rhodecode.model.changeset_status import ChangesetStatusModel
 from rhodecode.model.comment import ChangesetCommentsModel
 from rhodecode.model.db import PullRequest, ChangesetStatus, ChangesetComment, \
     Repository
 from rhodecode.model.forms import PullRequestForm
 from rhodecode.model.meta import Session
 from rhodecode.model.pull_request import PullRequestModel
 
 log = logging.getLogger(__name__)
 
 
 class PullrequestsController(BaseRepoController):
     def __before__(self):
         super(PullrequestsController, self).__before__()
 
     def _load_compare_data(self, pull_request, enable_comments=True):
         """
         Load context data needed for generating compare diff
 
         :param pull_request: object related to the request
         :param enable_comments: flag to determine if comments are included
         """
         source_repo = pull_request.source_repo
         source_ref_id = pull_request.source_ref_parts.commit_id
 
         target_repo = pull_request.target_repo
         target_ref_id = pull_request.target_ref_parts.commit_id
 
         # despite opening commits for bookmarks/branches/tags, we always
         # convert this to rev to prevent changes after bookmark or branch change
         c.source_ref_type = 'rev'
         c.source_ref = source_ref_id
 
         c.target_ref_type = 'rev'
         c.target_ref = target_ref_id
 
         c.source_repo = source_repo
         c.target_repo = target_repo
 
         c.fulldiff = bool(request.GET.get('fulldiff'))
 
         # diff_limit is the old behavior, will cut off the whole diff
         # if the limit is applied  otherwise will just hide the
         # big files from the front-end
         diff_limit = self.cut_off_limit_diff
         file_limit = self.cut_off_limit_file
 
         pre_load = ["author", "branch", "date", "message"]
 
         c.commit_ranges = []
         source_commit = EmptyCommit()
         target_commit = EmptyCommit()
         c.missing_requirements = False
         try:
             c.commit_ranges = [
                 source_repo.get_commit(commit_id=rev, pre_load=pre_load)
                 for rev in pull_request.revisions]
 
             c.statuses = source_repo.statuses(
                 [x.raw_id for x in c.commit_ranges])
 
             target_commit = source_repo.get_commit(
                 commit_id=safe_str(target_ref_id))
             source_commit = source_repo.get_commit(
                 commit_id=safe_str(source_ref_id))
         except RepositoryRequirementError:
             c.missing_requirements = True
 
         c.missing_commits = False
         if (c.missing_requirements or
                 isinstance(source_commit, EmptyCommit) or
                     source_commit == target_commit):
             _parsed = []
             c.missing_commits = True
         else:
             vcs_diff = PullRequestModel().get_diff(pull_request)
             diff_processor = diffs.DiffProcessor(
                 vcs_diff, format='gitdiff', diff_limit=diff_limit,
                 file_limit=file_limit, show_full_diff=c.fulldiff)
             _parsed = diff_processor.prepare()
 
         c.limited_diff = isinstance(_parsed, LimitedDiffContainer)
 
         c.files = []
         c.changes = {}
         c.lines_added = 0
         c.lines_deleted = 0
         c.included_files = []
         c.deleted_files = []
 
         for f in _parsed:
             st = f['stats']
             c.lines_added += st['added']
             c.lines_deleted += st['deleted']
 
             fid = h.FID('', f['filename'])
             c.files.append([fid, f['operation'], f['filename'], f['stats']])
             c.included_files.append(f['filename'])
             html_diff = diff_processor.as_html(enable_comments=enable_comments,
                                                parsed_lines=[f])
             c.changes[fid] = [f['operation'], f['filename'], html_diff, f]
 
     def _extract_ordering(self, request):
         column_index = safe_int(request.GET.get('order[0][column]'))
         order_dir = request.GET.get('order[0][dir]', 'desc')
         order_by = request.GET.get(
             'columns[%s][data][sort]' % column_index, 'name_raw')
         return order_by, order_dir
 
     @LoginRequired()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @HasAcceptedRepoType('git', 'hg')
     def show_all(self, repo_name):
         # filter types
         c.active = 'open'
         c.source = str2bool(request.GET.get('source'))
         c.closed = str2bool(request.GET.get('closed'))
         c.my = str2bool(request.GET.get('my'))
         c.awaiting_review = str2bool(request.GET.get('awaiting_review'))
         c.awaiting_my_review = str2bool(request.GET.get('awaiting_my_review'))
         c.repo_name = repo_name
 
         opened_by = None
         if c.my:
             c.active = 'my'
             opened_by = [c.rhodecode_user.user_id]
 
         statuses = [PullRequest.STATUS_NEW, PullRequest.STATUS_OPEN]
         if c.closed:
             c.active = 'closed'
             statuses = [PullRequest.STATUS_CLOSED]
 
         if c.awaiting_review and not c.source:
             c.active = 'awaiting'
         if c.source and not c.awaiting_review:
             c.active = 'source'
         if c.awaiting_my_review:
             c.active = 'awaiting_my'
 
         data = self._get_pull_requests_list(
             repo_name=repo_name, opened_by=opened_by, statuses=statuses)
         if not request.is_xhr:
             c.data = json.dumps(data['data'])
             c.records_total = data['recordsTotal']
             return render('/pullrequests/pullrequests.html')
         else:
             return json.dumps(data)
 
     def _get_pull_requests_list(self, repo_name, opened_by, statuses):
         # pagination
         start = safe_int(request.GET.get('start'), 0)
         length = safe_int(request.GET.get('length'), c.visual.dashboard_items)
         order_by, order_dir = self._extract_ordering(request)
 
         if c.awaiting_review:
             pull_requests = PullRequestModel().get_awaiting_review(
                 repo_name, source=c.source, opened_by=opened_by,
                 statuses=statuses, offset=start, length=length,
                 order_by=order_by, order_dir=order_dir)
             pull_requests_total_count = PullRequestModel(
             ).count_awaiting_review(
                 repo_name, source=c.source, statuses=statuses,
                 opened_by=opened_by)
         elif c.awaiting_my_review:
             pull_requests = PullRequestModel().get_awaiting_my_review(
                 repo_name, source=c.source, opened_by=opened_by,
                 user_id=c.rhodecode_user.user_id, statuses=statuses,
                 offset=start, length=length, order_by=order_by,
                 order_dir=order_dir)
             pull_requests_total_count = PullRequestModel(
             ).count_awaiting_my_review(
                 repo_name, source=c.source, user_id=c.rhodecode_user.user_id,
                 statuses=statuses, opened_by=opened_by)
         else:
             pull_requests = PullRequestModel().get_all(
                 repo_name, source=c.source, opened_by=opened_by,
                 statuses=statuses, offset=start, length=length,
                 order_by=order_by, order_dir=order_dir)
             pull_requests_total_count = PullRequestModel().count_all(
                 repo_name, source=c.source, statuses=statuses,
                 opened_by=opened_by)
 
         from rhodecode.lib.utils import PartialRenderer
         _render = PartialRenderer('data_table/_dt_elements.html')
         data = []
         for pr in pull_requests:
             comments = ChangesetCommentsModel().get_all_comments(
                 c.rhodecode_db_repo.repo_id, pull_request=pr)
 
             data.append({
                 'name': _render('pullrequest_name',
                                 pr.pull_request_id, pr.target_repo.repo_name),
                 'name_raw': pr.pull_request_id,
                 'status': _render('pullrequest_status',
                                   pr.calculated_review_status()),
                 'title': _render(
                     'pullrequest_title', pr.title, pr.description),
                 'description': h.escape(pr.description),
                 'updated_on': _render('pullrequest_updated_on',
                                       h.datetime_to_time(pr.updated_on)),
                 'updated_on_raw': h.datetime_to_time(pr.updated_on),
                 'created_on': _render('pullrequest_updated_on',
                                       h.datetime_to_time(pr.created_on)),
                 'created_on_raw': h.datetime_to_time(pr.created_on),
                 'author': _render('pullrequest_author',
                                   pr.author.full_contact, ),
                 'author_raw': pr.author.full_name,
                 'comments': _render('pullrequest_comments', len(comments)),
                 'comments_raw': len(comments),
                 'closed': pr.is_closed(),
             })
         # json used to render the grid
         data = ({
             'data': data,
             'recordsTotal': pull_requests_total_count,
             'recordsFiltered': pull_requests_total_count,
         })
         return data
 
     @LoginRequired()
     @NotAnonymous()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @HasAcceptedRepoType('git', 'hg')
     def index(self):
         source_repo = c.rhodecode_db_repo
 
         try:
             source_repo.scm_instance().get_commit()
         except EmptyRepositoryError:
             h.flash(h.literal(_('There are no commits yet')),
                     category='warning')
             redirect(url('summary_home', repo_name=source_repo.repo_name))
 
         commit_id = request.GET.get('commit')
         branch_ref = request.GET.get('branch')
         bookmark_ref = request.GET.get('bookmark')
 
         try:
             source_repo_data = PullRequestModel().generate_repo_data(
                 source_repo, commit_id=commit_id,
                 branch=branch_ref, bookmark=bookmark_ref)
         except CommitDoesNotExistError as e:
             log.exception(e)
             h.flash(_('Commit does not exist'), 'error')
             redirect(url('pullrequest_home', repo_name=source_repo.repo_name))
 
         default_target_repo = source_repo
 
         if source_repo.parent:
             parent_vcs_obj = source_repo.parent.scm_instance()
             if parent_vcs_obj and not parent_vcs_obj.is_empty():
                 # change default if we have a parent repo
                 default_target_repo = source_repo.parent
 
         target_repo_data = PullRequestModel().generate_repo_data(
             default_target_repo)
 
         selected_source_ref = source_repo_data['refs']['selected_ref']
 
         title_source_ref = selected_source_ref.split(':', 2)[1]
         c.default_title = PullRequestModel().generate_pullrequest_title(
             source=source_repo.repo_name,
             source_ref=title_source_ref,
             target=default_target_repo.repo_name
         )
 
         c.default_repo_data = {
             'source_repo_name': source_repo.repo_name,
             'source_refs_json': json.dumps(source_repo_data),
             'target_repo_name': default_target_repo.repo_name,
             'target_refs_json': json.dumps(target_repo_data),
         }
         c.default_source_ref = selected_source_ref
 
         return render('/pullrequests/pullrequest.html')
 
     @LoginRequired()
     @NotAnonymous()
     @XHRRequired()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @jsonify
     def get_repo_refs(self, repo_name, target_repo_name):
         repo = Repository.get_by_repo_name(target_repo_name)
         if not repo:
             raise HTTPNotFound
         return PullRequestModel().generate_repo_data(repo)
 
     @LoginRequired()
     @NotAnonymous()
     @XHRRequired()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @jsonify
     def get_repo_destinations(self, repo_name):
         repo = Repository.get_by_repo_name(repo_name)
         if not repo:
             raise HTTPNotFound
         filter_query = request.GET.get('query')
 
         query = Repository.query() \
             .order_by(func.length(Repository.repo_name)) \
             .filter(or_(
             Repository.repo_name == repo.repo_name,
             Repository.fork_id == repo.repo_id))
 
         if filter_query:
             ilike_expression = u'%{}%'.format(safe_unicode(filter_query))
             query = query.filter(
                 Repository.repo_name.ilike(ilike_expression))
 
         add_parent = False
         if repo.parent:
             if filter_query in repo.parent.repo_name:
                 parent_vcs_obj = repo.parent.scm_instance()
                 if parent_vcs_obj and not parent_vcs_obj.is_empty():
                     add_parent = True
 
         limit = 20 - 1 if add_parent else 20
         all_repos = query.limit(limit).all()
         if add_parent:
             all_repos += [repo.parent]
 
         repos = []
         for obj in self.scm_model.get_repos(all_repos):
             repos.append({
                 'id': obj['name'],
                 'text': obj['name'],
                 'type': 'repo',
                 'obj': obj['dbrepo']
             })
 
         data = {
             'more': False,
             'results': [{
                 'text': _('Repositories'),
                 'children': repos
             }] if repos else []
         }
         return data
 
     @LoginRequired()
     @NotAnonymous()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @HasAcceptedRepoType('git', 'hg')
     @auth.CSRFRequired()
     def create(self, repo_name):
         repo = Repository.get_by_repo_name(repo_name)
         if not repo:
             raise HTTPNotFound
 
         controls = peppercorn.parse(request.POST.items())
 
         try:
             _form = PullRequestForm(repo.repo_id)().to_python(controls)
         except formencode.Invalid as errors:
             if errors.error_dict.get('revisions'):
                 msg = 'Revisions: %s' % errors.error_dict['revisions']
             elif errors.error_dict.get('pullrequest_title'):
                 msg = _('Pull request requires a title with min. 3 chars')
             else:
                 msg = _('Error creating pull request: {}').format(errors)
             log.exception(msg)
             h.flash(msg, 'error')
 
             # would rather just go back to form ...
             return redirect(url('pullrequest_home', repo_name=repo_name))
 
         source_repo = _form['source_repo']
         source_ref = _form['source_ref']
         target_repo = _form['target_repo']
         target_ref = _form['target_ref']
         commit_ids = _form['revisions'][::-1]
         reviewers = [
             (r['user_id'], r['reasons']) for r in _form['review_members']]
 
         # find the ancestor for this pr
         source_db_repo = Repository.get_by_repo_name(_form['source_repo'])
         target_db_repo = Repository.get_by_repo_name(_form['target_repo'])
 
         source_scm = source_db_repo.scm_instance()
         target_scm = target_db_repo.scm_instance()
 
         source_commit = source_scm.get_commit(source_ref.split(':')[-1])
         target_commit = target_scm.get_commit(target_ref.split(':')[-1])
 
         ancestor = source_scm.get_common_ancestor(
             source_commit.raw_id, target_commit.raw_id, target_scm)
 
         target_ref_type, target_ref_name, __ = _form['target_ref'].split(':')
         target_ref = ':'.join((target_ref_type, target_ref_name, ancestor))
 
         pullrequest_title = _form['pullrequest_title']
         title_source_ref = source_ref.split(':', 2)[1]
         if not pullrequest_title:
             pullrequest_title = PullRequestModel().generate_pullrequest_title(
                 source=source_repo,
                 source_ref=title_source_ref,
                 target=target_repo
             )
 
         description = _form['pullrequest_desc']
         try:
             pull_request = PullRequestModel().create(
                 c.rhodecode_user.user_id, source_repo, source_ref, target_repo,
                 target_ref, commit_ids, reviewers, pullrequest_title,
                 description
             )
             Session().commit()
             h.flash(_('Successfully opened new pull request'),
                     category='success')
         except Exception as e:
             msg = _('Error occurred during sending pull request')
             log.exception(msg)
             h.flash(msg, category='error')
             return redirect(url('pullrequest_home', repo_name=repo_name))
 
         return redirect(url('pullrequest_show', repo_name=target_repo,
                             pull_request_id=pull_request.pull_request_id))
 
     @LoginRequired()
     @NotAnonymous()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @auth.CSRFRequired()
     @jsonify
     def update(self, repo_name, pull_request_id):
         pull_request_id = safe_int(pull_request_id)
         pull_request = PullRequest.get_or_404(pull_request_id)
         # only owner or admin can update it
         allowed_to_update = PullRequestModel().check_user_update(
             pull_request, c.rhodecode_user)
         if allowed_to_update:
             controls = peppercorn.parse(request.POST.items())
 
             if 'review_members' in controls:
                 self._update_reviewers(
                     pull_request_id, controls['review_members'])
             elif str2bool(request.POST.get('update_commits', 'false')):
                 self._update_commits(pull_request)
             elif str2bool(request.POST.get('close_pull_request', 'false')):
                 self._reject_close(pull_request)
             elif str2bool(request.POST.get('edit_pull_request', 'false')):
                 self._edit_pull_request(pull_request)
             else:
                 raise HTTPBadRequest()
             return True
         raise HTTPForbidden()
 
     def _edit_pull_request(self, pull_request):
         try:
             PullRequestModel().edit(
                 pull_request, request.POST.get('title'),
                 request.POST.get('description'))
         except ValueError:
             msg = _(u'Cannot update closed pull requests.')
             h.flash(msg, category='error')
             return
         else:
             Session().commit()
 
         msg = _(u'Pull request title & description updated.')
         h.flash(msg, category='success')
         return
 
     def _update_commits(self, pull_request):
         resp = PullRequestModel().update_commits(pull_request)
-        msg = PullRequestModel.UPDATE_STATUS_MESSAGES[resp.reason]
 
-        # Abort if pull request update failed.
-        if not resp.success:
-            h.flash(msg, category='error')
-            return
-
-        if resp.reason == UpdateFailureReason.NONE:
+        if resp.success:
             msg = _(
                 u'Pull request updated to "{source_commit_id}" with '
                 u'{count_added} added, {count_removed} removed commits.')
             msg = msg.format(
                 source_commit_id=pull_request.source_ref_parts.commit_id,
                 count_added=len(resp.changes.added),
                 count_removed=len(resp.changes.removed))
             h.flash(msg, category='success')
 
             registry = get_current_registry()
             rhodecode_plugins = getattr(registry, 'rhodecode_plugins', {})
             channelstream_config = rhodecode_plugins.get('channelstream', {})
             if channelstream_config.get('enabled'):
                 message = msg + (
                     ' - <a onclick="window.location.reload()">'
                     '<strong>{}</strong></a>'.format(_('Reload page')))
                 channel = '/repo${}$/pr/{}'.format(
                     pull_request.target_repo.repo_name,
                     pull_request.pull_request_id
                 )
                 payload = {
                     'type': 'message',
                     'user': 'system',
                     'exclude_users': [request.user.username],
                     'channel': channel,
                     'message': {
                         'message': message,
                         'level': 'success',
                         'topic': '/notifications'
                     }
                 }
                 channelstream_request(
                     channelstream_config, [payload], '/message',
                     raise_exc=False)
-        elif resp.reason == UpdateFailureReason.NO_CHANGE:
-            # Display a warning if no update is needed.
-            h.flash(msg, category='warning')
         else:
-            h.flash(msg, category='error')
+            msg = PullRequestModel.UPDATE_STATUS_MESSAGES[resp.reason]
+            warning_reasons = [
+                UpdateFailureReason.NO_CHANGE,
+                UpdateFailureReason.WRONG_REF_TPYE,
+            ]
+            category = 'warning' if resp.reason in warning_reasons else 'error'
+            h.flash(msg, category=category)
 
     @auth.CSRFRequired()
     @LoginRequired()
     @NotAnonymous()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     def merge(self, repo_name, pull_request_id):
         """
         POST /{repo_name}/pull-request/{pull_request_id}
 
         Merge will perform a server-side merge of the specified
         pull request, if the pull request is approved and mergeable.
         After succesfull merging, the pull request is automatically
         closed, with a relevant comment.
         """
         pull_request_id = safe_int(pull_request_id)
         pull_request = PullRequest.get_or_404(pull_request_id)
         user = c.rhodecode_user
 
         if self._meets_merge_pre_conditions(pull_request, user):
             log.debug("Pre-conditions checked, trying to merge.")
             extras = vcs_operation_context(
                 request.environ, repo_name=pull_request.target_repo.repo_name,
                 username=user.username, action='push',
                 scm=pull_request.target_repo.repo_type)
             self._merge_pull_request(pull_request, user, extras)
 
         return redirect(url(
             'pullrequest_show',
             repo_name=pull_request.target_repo.repo_name,
             pull_request_id=pull_request.pull_request_id))
 
     def _meets_merge_pre_conditions(self, pull_request, user):
         if not PullRequestModel().check_user_merge(pull_request, user):
             raise HTTPForbidden()
 
         merge_status, msg = PullRequestModel().merge_status(pull_request)
         if not merge_status:
             log.debug("Cannot merge, not mergeable.")
             h.flash(msg, category='error')
             return False
 
         if (pull_request.calculated_review_status()
             is not ChangesetStatus.STATUS_APPROVED):
             log.debug("Cannot merge, approval is pending.")
             msg = _('Pull request reviewer approval is pending.')
             h.flash(msg, category='error')
             return False
         return True
 
     def _merge_pull_request(self, pull_request, user, extras):
         merge_resp = PullRequestModel().merge(
             pull_request, user, extras=extras)
 
         if merge_resp.executed:
             log.debug("The merge was successful, closing the pull request.")
             PullRequestModel().close_pull_request(
                 pull_request.pull_request_id, user)
             Session().commit()
             msg = _('Pull request was successfully merged and closed.')
             h.flash(msg, category='success')
         else:
             log.debug(
                 "The merge was not successful. Merge response: %s",
                 merge_resp)
             msg = PullRequestModel().merge_status_message(
                 merge_resp.failure_reason)
             h.flash(msg, category='error')
 
     def _update_reviewers(self, pull_request_id, review_members):
         reviewers = [
             (int(r['user_id']), r['reasons']) for r in review_members]
         PullRequestModel().update_reviewers(pull_request_id, reviewers)
         Session().commit()
 
     def _reject_close(self, pull_request):
         if pull_request.is_closed():
             raise HTTPForbidden()
 
         PullRequestModel().close_pull_request_with_comment(
             pull_request, c.rhodecode_user, c.rhodecode_db_repo)
         Session().commit()
 
     @LoginRequired()
     @NotAnonymous()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @auth.CSRFRequired()
     @jsonify
     def delete(self, repo_name, pull_request_id):
         pull_request_id = safe_int(pull_request_id)
         pull_request = PullRequest.get_or_404(pull_request_id)
         # only owner can delete it !
         if pull_request.author.user_id == c.rhodecode_user.user_id:
             PullRequestModel().delete(pull_request)
             Session().commit()
             h.flash(_('Successfully deleted pull request'),
                     category='success')
             return redirect(url('my_account_pullrequests'))
         raise HTTPForbidden()
 
     @LoginRequired()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     def show(self, repo_name, pull_request_id):
         pull_request_id = safe_int(pull_request_id)
         c.pull_request = PullRequest.get_or_404(pull_request_id)
 
         c.template_context['pull_request_data']['pull_request_id'] = \
             pull_request_id
 
         # pull_requests repo_name we opened it against
         # ie. target_repo must match
         if repo_name != c.pull_request.target_repo.repo_name:
             raise HTTPNotFound
 
         c.allowed_to_change_status = PullRequestModel(). \
             check_user_change_status(c.pull_request, c.rhodecode_user)
         c.allowed_to_update = PullRequestModel().check_user_update(
             c.pull_request, c.rhodecode_user) and not c.pull_request.is_closed()
         c.allowed_to_merge = PullRequestModel().check_user_merge(
             c.pull_request, c.rhodecode_user) and not c.pull_request.is_closed()
         c.shadow_clone_url = PullRequestModel().get_shadow_clone_url(
             c.pull_request)
 
         cc_model = ChangesetCommentsModel()
 
         c.pull_request_reviewers = c.pull_request.reviewers_statuses()
 
         c.pull_request_review_status = c.pull_request.calculated_review_status()
         c.pr_merge_status, c.pr_merge_msg = PullRequestModel().merge_status(
             c.pull_request)
         c.approval_msg = None
         if c.pull_request_review_status != ChangesetStatus.STATUS_APPROVED:
             c.approval_msg = _('Reviewer approval is pending.')
             c.pr_merge_status = False
         # load compare data into template context
         enable_comments = not c.pull_request.is_closed()
         self._load_compare_data(c.pull_request, enable_comments=enable_comments)
 
         # this is a hack to properly display links, when creating PR, the
         # compare view and others uses different notation, and
         # compare_commits.html renders links based on the target_repo.
         # We need to swap that here to generate it properly on the html side
         c.target_repo = c.source_repo
 
         # inline comments
         c.inline_cnt = 0
         c.inline_comments = cc_model.get_inline_comments(
             c.rhodecode_db_repo.repo_id,
             pull_request=pull_request_id).items()
         # count inline comments
         for __, lines in c.inline_comments:
             for comments in lines.values():
                 c.inline_cnt += len(comments)
 
         # outdated comments
         c.outdated_cnt = 0
         if ChangesetCommentsModel.use_outdated_comments(c.pull_request):
             c.outdated_comments = cc_model.get_outdated_comments(
                 c.rhodecode_db_repo.repo_id,
                 pull_request=c.pull_request)
             # Count outdated comments and check for deleted files
             for file_name, lines in c.outdated_comments.iteritems():
                 for comments in lines.values():
                     c.outdated_cnt += len(comments)
                 if file_name not in c.included_files:
                     c.deleted_files.append(file_name)
         else:
             c.outdated_comments = {}
 
         # comments
         c.comments = cc_model.get_comments(c.rhodecode_db_repo.repo_id,
                                            pull_request=pull_request_id)
 
         if c.allowed_to_update:
             force_close = ('forced_closed', _('Close Pull Request'))
             statuses = ChangesetStatus.STATUSES + [force_close]
         else:
             statuses = ChangesetStatus.STATUSES
         c.commit_statuses = statuses
 
         c.ancestor = None # TODO: add ancestor here
 
         return render('/pullrequests/pullrequest_show.html')
 
     @LoginRequired()
     @NotAnonymous()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @auth.CSRFRequired()
     @jsonify
     def comment(self, repo_name, pull_request_id):
         pull_request_id = safe_int(pull_request_id)
         pull_request = PullRequest.get_or_404(pull_request_id)
         if pull_request.is_closed():
             raise HTTPForbidden()
 
         # TODO: johbo: Re-think this bit, "approved_closed" does not exist
         # as a changeset status, still we want to send it in one value.
         status = request.POST.get('changeset_status', None)
         text = request.POST.get('text')
         if status and '_closed' in status:
             close_pr = True
             status = status.replace('_closed', '')
         else:
             close_pr = False
 
         forced = (status == 'forced')
         if forced:
             status = 'rejected'
 
         allowed_to_change_status = PullRequestModel().check_user_change_status(
             pull_request, c.rhodecode_user)
 
         if status and allowed_to_change_status:
             message = (_('Status change %(transition_icon)s %(status)s')
                        % {'transition_icon': '>',
                           'status': ChangesetStatus.get_status_lbl(status)})
             if close_pr:
                 message = _('Closing with') + ' ' + message
             text = text or message
         comm = ChangesetCommentsModel().create(
             text=text,
             repo=c.rhodecode_db_repo.repo_id,
             user=c.rhodecode_user.user_id,
             pull_request=pull_request_id,
             f_path=request.POST.get('f_path'),
             line_no=request.POST.get('line'),
             status_change=(ChangesetStatus.get_status_lbl(status)
                            if status and allowed_to_change_status else None),
             status_change_type=(status
                                 if status and allowed_to_change_status else None),
             closing_pr=close_pr
         )
 
 
 
         if allowed_to_change_status:
             old_calculated_status = pull_request.calculated_review_status()
             # get status if set !
             if status:
                 ChangesetStatusModel().set_status(
                     c.rhodecode_db_repo.repo_id,
                     status,
                     c.rhodecode_user.user_id,
                     comm,
                     pull_request=pull_request_id
                 )
 
             Session().flush()
             events.trigger(events.PullRequestCommentEvent(pull_request, comm))
             # we now calculate the status of pull request, and based on that
             # calculation we set the commits status
             calculated_status = pull_request.calculated_review_status()
             if old_calculated_status != calculated_status:
                 PullRequestModel()._trigger_pull_request_hook(
                     pull_request, c.rhodecode_user, 'review_status_change')
 
             calculated_status_lbl = ChangesetStatus.get_status_lbl(
                 calculated_status)
 
             if close_pr:
                 status_completed = (
                     calculated_status in [ChangesetStatus.STATUS_APPROVED,
                                           ChangesetStatus.STATUS_REJECTED])
                 if forced or status_completed:
                     PullRequestModel().close_pull_request(
                         pull_request_id, c.rhodecode_user)
                 else:
                     h.flash(_('Closing pull request on other statuses than '
                               'rejected or approved is forbidden. '
                               'Calculated status from all reviewers '
                               'is currently: %s') % calculated_status_lbl,
                             category='warning')
 
         Session().commit()
 
         if not request.is_xhr:
             return redirect(h.url('pullrequest_show', repo_name=repo_name,
                                   pull_request_id=pull_request_id))
 
         data = {
             'target_id': h.safeid(h.safe_unicode(request.POST.get('f_path'))),
         }
         if comm:
             c.co = comm
             data.update(comm.get_dict())
             data.update({'rendered_text':
                              render('changeset/changeset_comment_block.html')})
 
         return data
 
     @LoginRequired()
     @NotAnonymous()
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     @auth.CSRFRequired()
     @jsonify
     def delete_comment(self, repo_name, comment_id):
         return self._delete_comment(comment_id)
 
     def _delete_comment(self, comment_id):
         comment_id = safe_int(comment_id)
         co = ChangesetComment.get_or_404(comment_id)
         if co.pull_request.is_closed():
             # don't allow deleting comments on closed pull request
             raise HTTPForbidden()
 
         is_owner = co.author.user_id == c.rhodecode_user.user_id
         is_repo_admin = h.HasRepoPermissionAny('repository.admin')(c.repo_name)
         if h.HasPermissionAny('hg.admin')() or is_repo_admin or is_owner:
             old_calculated_status = co.pull_request.calculated_review_status()
             ChangesetCommentsModel().delete(comment=co)
             Session().commit()
             calculated_status = co.pull_request.calculated_review_status()
             if old_calculated_status != calculated_status:
                 PullRequestModel()._trigger_pull_request_hook(
                     co.pull_request, c.rhodecode_user, 'review_status_change')
             return True
         else:
             raise HTTPForbidden()

rhodecode/model/pull_request.py

@@ -1,1250 +1,1250 b''
 # -*- coding: utf-8 -*-
 
 # Copyright (C) 2012-2016  RhodeCode GmbH
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU Affero General Public License, version 3
 # (only), as published by the Free Software Foundation.
 #
 # 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 Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 # This program is dual-licensed. If you wish to learn more about the
 # RhodeCode Enterprise Edition, including its added features, Support services,
 # and proprietary license terms, please see https://rhodecode.com/licenses/
 
 
 """
 pull request model for RhodeCode
 """
 
 from collections import namedtuple
 import json
 import logging
 import datetime
 import urllib
 
 from pylons.i18n.translation import _
 from pylons.i18n.translation import lazy_ugettext
 
 from rhodecode.lib import helpers as h, hooks_utils, diffs
 from rhodecode.lib.compat import OrderedDict
 from rhodecode.lib.hooks_daemon import prepare_callback_daemon
 from rhodecode.lib.markup_renderer import (
     DEFAULT_COMMENTS_RENDERER, RstTemplateRenderer)
 from rhodecode.lib.utils import action_logger
 from rhodecode.lib.utils2 import safe_unicode, safe_str, md5_safe
 from rhodecode.lib.vcs.backends.base import (
     Reference, MergeResponse, MergeFailureReason, UpdateFailureReason)
 from rhodecode.lib.vcs.conf import settings as vcs_settings
 from rhodecode.lib.vcs.exceptions import (
     CommitDoesNotExistError, EmptyRepositoryError)
 from rhodecode.model import BaseModel
 from rhodecode.model.changeset_status import ChangesetStatusModel
 from rhodecode.model.comment import ChangesetCommentsModel
 from rhodecode.model.db import (
     PullRequest, PullRequestReviewers, ChangesetStatus,
     PullRequestVersion, ChangesetComment)
 from rhodecode.model.meta import Session
 from rhodecode.model.notification import NotificationModel, \
     EmailNotificationModel
 from rhodecode.model.scm import ScmModel
 from rhodecode.model.settings import VcsSettingsModel
 
 
 log = logging.getLogger(__name__)
 
 
 # Data structure to hold the response data when updating commits during a pull
 # request update.
 UpdateResponse = namedtuple(
     'UpdateResponse', 'success, reason, new, old, changes')
 
 
 class PullRequestModel(BaseModel):
 
     cls = PullRequest
 
     DIFF_CONTEXT = 3
 
     MERGE_STATUS_MESSAGES = {
         MergeFailureReason.NONE: lazy_ugettext(
             'This pull request can be automatically merged.'),
         MergeFailureReason.UNKNOWN: lazy_ugettext(
             'This pull request cannot be merged because of an unhandled'
             ' exception.'),
         MergeFailureReason.MERGE_FAILED: lazy_ugettext(
             'This pull request cannot be merged because of conflicts.'),
         MergeFailureReason.PUSH_FAILED: lazy_ugettext(
             'This pull request could not be merged because push to target'
             ' failed.'),
         MergeFailureReason.TARGET_IS_NOT_HEAD: lazy_ugettext(
             'This pull request cannot be merged because the target is not a'
             ' head.'),
         MergeFailureReason.HG_SOURCE_HAS_MORE_BRANCHES: lazy_ugettext(
             'This pull request cannot be merged because the source contains'
             ' more branches than the target.'),
         MergeFailureReason.HG_TARGET_HAS_MULTIPLE_HEADS: lazy_ugettext(
             'This pull request cannot be merged because the target has'
             ' multiple heads.'),
         MergeFailureReason.TARGET_IS_LOCKED: lazy_ugettext(
             'This pull request cannot be merged because the target repository'
             ' is locked.'),
         MergeFailureReason._DEPRECATED_MISSING_COMMIT: lazy_ugettext(
             'This pull request cannot be merged because the target or the '
             'source reference is missing.'),
         MergeFailureReason.MISSING_TARGET_REF: lazy_ugettext(
             'This pull request cannot be merged because the target '
             'reference is missing.'),
         MergeFailureReason.MISSING_SOURCE_REF: lazy_ugettext(
             'This pull request cannot be merged because the source '
             'reference is missing.'),
     }
 
     UPDATE_STATUS_MESSAGES = {
         UpdateFailureReason.NONE: lazy_ugettext(
             'Pull request update successful.'),
         UpdateFailureReason.UNKNOWN: lazy_ugettext(
             'Pull request update failed because of an unknown error.'),
         UpdateFailureReason.NO_CHANGE: lazy_ugettext(
             'No update needed because the source reference is already '
             'up to date.'),
         UpdateFailureReason.WRONG_REF_TPYE: lazy_ugettext(
             'Pull request cannot be updated because the reference type is '
             'not supported for an update.'),
         UpdateFailureReason.MISSING_TARGET_REF: lazy_ugettext(
             'This pull request cannot be updated because the target '
             'reference is missing.'),
         UpdateFailureReason.MISSING_SOURCE_REF: lazy_ugettext(
             'This pull request cannot be updated because the source '
             'reference is missing.'),
     }
 
     def __get_pull_request(self, pull_request):
         return self._get_instance(PullRequest, pull_request)
 
     def _check_perms(self, perms, pull_request, user, api=False):
         if not api:
             return h.HasRepoPermissionAny(*perms)(
                 user=user, repo_name=pull_request.target_repo.repo_name)
         else:
             return h.HasRepoPermissionAnyApi(*perms)(
                 user=user, repo_name=pull_request.target_repo.repo_name)
 
     def check_user_read(self, pull_request, user, api=False):
         _perms = ('repository.admin', 'repository.write', 'repository.read',)
         return self._check_perms(_perms, pull_request, user, api)
 
     def check_user_merge(self, pull_request, user, api=False):
         _perms = ('repository.admin', 'repository.write', 'hg.admin',)
         return self._check_perms(_perms, pull_request, user, api)
 
     def check_user_update(self, pull_request, user, api=False):
         owner = user.user_id == pull_request.user_id
         return self.check_user_merge(pull_request, user, api) or owner
 
     def check_user_change_status(self, pull_request, user, api=False):
         reviewer = user.user_id in [x.user_id for x in
                                     pull_request.reviewers]
         return self.check_user_update(pull_request, user, api) or reviewer
 
     def get(self, pull_request):
         return self.__get_pull_request(pull_request)
 
     def _prepare_get_all_query(self, repo_name, source=False, statuses=None,
                                opened_by=None, order_by=None,
                                order_dir='desc'):
         repo = self._get_repo(repo_name)
         q = PullRequest.query()
         # source or target
         if source:
             q = q.filter(PullRequest.source_repo == repo)
         else:
             q = q.filter(PullRequest.target_repo == repo)
 
         # closed,opened
         if statuses:
             q = q.filter(PullRequest.status.in_(statuses))
 
         # opened by filter
         if opened_by:
             q = q.filter(PullRequest.user_id.in_(opened_by))
 
         if order_by:
             order_map = {
                 'name_raw': PullRequest.pull_request_id,
                 'title': PullRequest.title,
                 'updated_on_raw': PullRequest.updated_on
             }
             if order_dir == 'asc':
                 q = q.order_by(order_map[order_by].asc())
             else:
                 q = q.order_by(order_map[order_by].desc())
 
         return q
 
     def count_all(self, repo_name, source=False, statuses=None,
                   opened_by=None):
         """
         Count the number of pull requests for a specific repository.
 
         :param repo_name: target or source repo
         :param source: boolean flag to specify if repo_name refers to source
         :param statuses: list of pull request statuses
         :param opened_by: author user of the pull request
         :returns: int number of pull requests
         """
         q = self._prepare_get_all_query(
             repo_name, source=source, statuses=statuses, opened_by=opened_by)
 
         return q.count()
 
     def get_all(self, repo_name, source=False, statuses=None, opened_by=None,
                 offset=0, length=None, order_by=None, order_dir='desc'):
         """
         Get all pull requests for a specific repository.
 
         :param repo_name: target or source repo
         :param source: boolean flag to specify if repo_name refers to source
         :param statuses: list of pull request statuses
         :param opened_by: author user of the pull request
         :param offset: pagination offset
         :param length: length of returned list
         :param order_by: order of the returned list
         :param order_dir: 'asc' or 'desc' ordering direction
         :returns: list of pull requests
         """
         q = self._prepare_get_all_query(
             repo_name, source=source, statuses=statuses, opened_by=opened_by,
             order_by=order_by, order_dir=order_dir)
 
         if length:
             pull_requests = q.limit(length).offset(offset).all()
         else:
             pull_requests = q.all()
 
         return pull_requests
 
     def count_awaiting_review(self, repo_name, source=False, statuses=None,
                               opened_by=None):
         """
         Count the number of pull requests for a specific repository that are
         awaiting review.
 
         :param repo_name: target or source repo
         :param source: boolean flag to specify if repo_name refers to source
         :param statuses: list of pull request statuses
         :param opened_by: author user of the pull request
         :returns: int number of pull requests
         """
         pull_requests = self.get_awaiting_review(
             repo_name, source=source, statuses=statuses, opened_by=opened_by)
 
         return len(pull_requests)
 
     def get_awaiting_review(self, repo_name, source=False, statuses=None,
                             opened_by=None, offset=0, length=None,
                             order_by=None, order_dir='desc'):
         """
         Get all pull requests for a specific repository that are awaiting
         review.
 
         :param repo_name: target or source repo
         :param source: boolean flag to specify if repo_name refers to source
         :param statuses: list of pull request statuses
         :param opened_by: author user of the pull request
         :param offset: pagination offset
         :param length: length of returned list
         :param order_by: order of the returned list
         :param order_dir: 'asc' or 'desc' ordering direction
         :returns: list of pull requests
         """
         pull_requests = self.get_all(
             repo_name, source=source, statuses=statuses, opened_by=opened_by,
             order_by=order_by, order_dir=order_dir)
 
         _filtered_pull_requests = []
         for pr in pull_requests:
             status = pr.calculated_review_status()
             if status in [ChangesetStatus.STATUS_NOT_REVIEWED,
                           ChangesetStatus.STATUS_UNDER_REVIEW]:
                 _filtered_pull_requests.append(pr)
         if length:
             return _filtered_pull_requests[offset:offset+length]
         else:
             return _filtered_pull_requests
 
     def count_awaiting_my_review(self, repo_name, source=False, statuses=None,
                                  opened_by=None, user_id=None):
         """
         Count the number of pull requests for a specific repository that are
         awaiting review from a specific user.
 
         :param repo_name: target or source repo
         :param source: boolean flag to specify if repo_name refers to source
         :param statuses: list of pull request statuses
         :param opened_by: author user of the pull request
         :param user_id: reviewer user of the pull request
         :returns: int number of pull requests
         """
         pull_requests = self.get_awaiting_my_review(
             repo_name, source=source, statuses=statuses, opened_by=opened_by,
             user_id=user_id)
 
         return len(pull_requests)
 
     def get_awaiting_my_review(self, repo_name, source=False, statuses=None,
                                opened_by=None, user_id=None, offset=0,
                                length=None, order_by=None, order_dir='desc'):
         """
         Get all pull requests for a specific repository that are awaiting
         review from a specific user.
 
         :param repo_name: target or source repo
         :param source: boolean flag to specify if repo_name refers to source
         :param statuses: list of pull request statuses
         :param opened_by: author user of the pull request
         :param user_id: reviewer user of the pull request
         :param offset: pagination offset
         :param length: length of returned list
         :param order_by: order of the returned list
         :param order_dir: 'asc' or 'desc' ordering direction
         :returns: list of pull requests
         """
         pull_requests = self.get_all(
             repo_name, source=source, statuses=statuses, opened_by=opened_by,
             order_by=order_by, order_dir=order_dir)
 
         _my = PullRequestModel().get_not_reviewed(user_id)
         my_participation = []
         for pr in pull_requests:
             if pr in _my:
                 my_participation.append(pr)
         _filtered_pull_requests = my_participation
         if length:
             return _filtered_pull_requests[offset:offset+length]
         else:
             return _filtered_pull_requests
 
     def get_not_reviewed(self, user_id):
         return [
             x.pull_request for x in PullRequestReviewers.query().filter(
                 PullRequestReviewers.user_id == user_id).all()
         ]
 
     def get_versions(self, pull_request):
         """
         returns version of pull request sorted by ID descending
         """
         return PullRequestVersion.query()\
             .filter(PullRequestVersion.pull_request == pull_request)\
             .order_by(PullRequestVersion.pull_request_version_id.asc())\
             .all()
 
     def create(self, created_by, source_repo, source_ref, target_repo,
         target_ref, revisions, reviewers, title, description=None):
         created_by_user = self._get_user(created_by)
         source_repo = self._get_repo(source_repo)
         target_repo = self._get_repo(target_repo)
 
         pull_request = PullRequest()
         pull_request.source_repo = source_repo
         pull_request.source_ref = source_ref
         pull_request.target_repo = target_repo
         pull_request.target_ref = target_ref
         pull_request.revisions = revisions
         pull_request.title = title
         pull_request.description = description
         pull_request.author = created_by_user
 
         Session().add(pull_request)
         Session().flush()
 
         reviewer_ids = set()
         # members / reviewers
         for reviewer_object in reviewers:
             if isinstance(reviewer_object, tuple):
                 user_id, reasons = reviewer_object
             else:
                 user_id, reasons = reviewer_object, []
 
             user = self._get_user(user_id)
             reviewer_ids.add(user.user_id)
 
             reviewer = PullRequestReviewers(user, pull_request, reasons)
             Session().add(reviewer)
 
         # Set approval status to "Under Review" for all commits which are
         # part of this pull request.
         ChangesetStatusModel().set_status(
             repo=target_repo,
             status=ChangesetStatus.STATUS_UNDER_REVIEW,
             user=created_by_user,
             pull_request=pull_request
         )
 
         self.notify_reviewers(pull_request, reviewer_ids)
         self._trigger_pull_request_hook(
             pull_request, created_by_user, 'create')
 
         return pull_request
 
     def _trigger_pull_request_hook(self, pull_request, user, action):
         pull_request = self.__get_pull_request(pull_request)
         target_scm = pull_request.target_repo.scm_instance()
         if action == 'create':
             trigger_hook = hooks_utils.trigger_log_create_pull_request_hook
         elif action == 'merge':
             trigger_hook = hooks_utils.trigger_log_merge_pull_request_hook
         elif action == 'close':
             trigger_hook = hooks_utils.trigger_log_close_pull_request_hook
         elif action == 'review_status_change':
             trigger_hook = hooks_utils.trigger_log_review_pull_request_hook
         elif action == 'update':
             trigger_hook = hooks_utils.trigger_log_update_pull_request_hook
         else:
             return
 
         trigger_hook(
             username=user.username,
             repo_name=pull_request.target_repo.repo_name,
             repo_alias=target_scm.alias,
             pull_request=pull_request)
 
     def _get_commit_ids(self, pull_request):
         """
         Return the commit ids of the merged pull request.
 
         This method is not dealing correctly yet with the lack of autoupdates
         nor with the implicit target updates.
         For example: if a commit in the source repo is already in the target it
         will be reported anyways.
         """
         merge_rev = pull_request.merge_rev
         if merge_rev is None:
             raise ValueError('This pull request was not merged yet')
 
         commit_ids = list(pull_request.revisions)
         if merge_rev not in commit_ids:
             commit_ids.append(merge_rev)
 
         return commit_ids
 
     def merge(self, pull_request, user, extras):
         log.debug("Merging pull request %s", pull_request.pull_request_id)
         merge_state = self._merge_pull_request(pull_request, user, extras)
         if merge_state.executed:
             log.debug(
                 "Merge was successful, updating the pull request comments.")
             self._comment_and_close_pr(pull_request, user, merge_state)
             self._log_action('user_merged_pull_request', user, pull_request)
         else:
             log.warn("Merge failed, not updating the pull request.")
         return merge_state
 
     def _merge_pull_request(self, pull_request, user, extras):
         target_vcs = pull_request.target_repo.scm_instance()
         source_vcs = pull_request.source_repo.scm_instance()
         target_ref = self._refresh_reference(
             pull_request.target_ref_parts, target_vcs)
 
         message = _(
             'Merge pull request #%(pr_id)s from '
             '%(source_repo)s %(source_ref_name)s\n\n %(pr_title)s') % {
                 'pr_id': pull_request.pull_request_id,
                 'source_repo': source_vcs.name,
                 'source_ref_name': pull_request.source_ref_parts.name,
                 'pr_title': pull_request.title
             }
 
         workspace_id = self._workspace_id(pull_request)
         use_rebase = self._use_rebase_for_merging(pull_request)
 
         callback_daemon, extras = prepare_callback_daemon(
             extras, protocol=vcs_settings.HOOKS_PROTOCOL,
             use_direct_calls=vcs_settings.HOOKS_DIRECT_CALLS)
 
         with callback_daemon:
             # TODO: johbo: Implement a clean way to run a config_override
             # for a single call.
             target_vcs.config.set(
                 'rhodecode', 'RC_SCM_DATA', json.dumps(extras))
             merge_state = target_vcs.merge(
                 target_ref, source_vcs, pull_request.source_ref_parts,
                 workspace_id, user_name=user.username,
                 user_email=user.email, message=message, use_rebase=use_rebase)
         return merge_state
 
     def _comment_and_close_pr(self, pull_request, user, merge_state):
         pull_request.merge_rev = merge_state.merge_ref.commit_id
         pull_request.updated_on = datetime.datetime.now()
 
         ChangesetCommentsModel().create(
             text=unicode(_('Pull request merged and closed')),
             repo=pull_request.target_repo.repo_id,
             user=user.user_id,
             pull_request=pull_request.pull_request_id,
             f_path=None,
             line_no=None,
             closing_pr=True
         )
 
         Session().add(pull_request)
         Session().flush()
         # TODO: paris: replace invalidation with less radical solution
         ScmModel().mark_for_invalidation(
             pull_request.target_repo.repo_name)
         self._trigger_pull_request_hook(pull_request, user, 'merge')
 
     def has_valid_update_type(self, pull_request):
         source_ref_type = pull_request.source_ref_parts.type
         return source_ref_type in ['book', 'branch', 'tag']
 
     def update_commits(self, pull_request):
         """
         Get the updated list of commits for the pull request
         and return the new pull request version and the list
         of commits processed by this update action
         """
         pull_request = self.__get_pull_request(pull_request)
         source_ref_type = pull_request.source_ref_parts.type
         source_ref_name = pull_request.source_ref_parts.name
         source_ref_id = pull_request.source_ref_parts.commit_id
 
         if not self.has_valid_update_type(pull_request):
             log.debug(
                 "Skipping update of pull request %s due to ref type: %s",
                 pull_request, source_ref_type)
             return UpdateResponse(
                 success=False,
                 reason=UpdateFailureReason.WRONG_REF_TPYE,
                 old=pull_request, new=None, changes=None)
 
         source_repo = pull_request.source_repo.scm_instance()
         try:
             source_commit = source_repo.get_commit(commit_id=source_ref_name)
         except CommitDoesNotExistError:
             return UpdateResponse(
                 success=False,
                 reason=UpdateFailureReason.MISSING_SOURCE_REF,
                 old=pull_request, new=None, changes=None)
 
         if source_ref_id == source_commit.raw_id:
             log.debug("Nothing changed in pull request %s", pull_request)
             return UpdateResponse(
-                success=True,
+                success=False,
                 reason=UpdateFailureReason.NO_CHANGE,
                 old=pull_request, new=None, changes=None)
 
         # Finally there is a need for an update
         pull_request_version = self._create_version_from_snapshot(pull_request)
         self._link_comments_to_version(pull_request_version)
 
         target_ref_type = pull_request.target_ref_parts.type
         target_ref_name = pull_request.target_ref_parts.name
         target_ref_id = pull_request.target_ref_parts.commit_id
         target_repo = pull_request.target_repo.scm_instance()
 
         try:
             if target_ref_type in ('tag', 'branch', 'book'):
                 target_commit = target_repo.get_commit(target_ref_name)
             else:
                 target_commit = target_repo.get_commit(target_ref_id)
         except CommitDoesNotExistError:
             return UpdateResponse(
                 success=False,
                 reason=UpdateFailureReason.MISSING_TARGET_REF,
                 old=pull_request, new=None, changes=None)
 
         # re-compute commit ids
         old_commit_ids = set(pull_request.revisions)
         pre_load = ["author", "branch", "date", "message"]
         commit_ranges = target_repo.compare(
             target_commit.raw_id, source_commit.raw_id, source_repo, merge=True,
             pre_load=pre_load)
 
         ancestor = target_repo.get_common_ancestor(
             target_commit.raw_id, source_commit.raw_id, source_repo)
 
         pull_request.source_ref = '%s:%s:%s' % (
             source_ref_type, source_ref_name, source_commit.raw_id)
         pull_request.target_ref = '%s:%s:%s' % (
             target_ref_type, target_ref_name, ancestor)
         pull_request.revisions = [
             commit.raw_id for commit in reversed(commit_ranges)]
         pull_request.updated_on = datetime.datetime.now()
         Session().add(pull_request)
         new_commit_ids = set(pull_request.revisions)
 
         changes = self._calculate_commit_id_changes(
             old_commit_ids, new_commit_ids)
 
         old_diff_data, new_diff_data = self._generate_update_diffs(
             pull_request, pull_request_version)
 
         ChangesetCommentsModel().outdate_comments(
             pull_request, old_diff_data=old_diff_data,
             new_diff_data=new_diff_data)
 
         file_changes = self._calculate_file_changes(
             old_diff_data, new_diff_data)
 
         # Add an automatic comment to the pull request
         update_comment = ChangesetCommentsModel().create(
             text=self._render_update_message(changes, file_changes),
             repo=pull_request.target_repo,
             user=pull_request.author,
             pull_request=pull_request,
             send_email=False, renderer=DEFAULT_COMMENTS_RENDERER)
 
         # Update status to "Under Review" for added commits
         for commit_id in changes.added:
             ChangesetStatusModel().set_status(
                 repo=pull_request.source_repo,
                 status=ChangesetStatus.STATUS_UNDER_REVIEW,
                 comment=update_comment,
                 user=pull_request.author,
                 pull_request=pull_request,
                 revision=commit_id)
 
         log.debug(
             'Updated pull request %s, added_ids: %s, common_ids: %s, '
             'removed_ids: %s', pull_request.pull_request_id,
             changes.added, changes.common, changes.removed)
         log.debug('Updated pull request with the following file changes: %s',
                   file_changes)
 
         log.info(
             "Updated pull request %s from commit %s to commit %s, "
             "stored new version %s of this pull request.",
             pull_request.pull_request_id, source_ref_id,
             pull_request.source_ref_parts.commit_id,
             pull_request_version.pull_request_version_id)
         Session().commit()
         self._trigger_pull_request_hook(pull_request, pull_request.author,
                                         'update')
 
         return UpdateResponse(
             success=True, reason=UpdateFailureReason.NONE,
             old=pull_request, new=pull_request_version, changes=changes)
 
     def _create_version_from_snapshot(self, pull_request):
         version = PullRequestVersion()
         version.title = pull_request.title
         version.description = pull_request.description
         version.status = pull_request.status
         version.created_on = pull_request.created_on
         version.updated_on = pull_request.updated_on
         version.user_id = pull_request.user_id
         version.source_repo = pull_request.source_repo
         version.source_ref = pull_request.source_ref
         version.target_repo = pull_request.target_repo
         version.target_ref = pull_request.target_ref
 
         version._last_merge_source_rev = pull_request._last_merge_source_rev
         version._last_merge_target_rev = pull_request._last_merge_target_rev
         version._last_merge_status = pull_request._last_merge_status
         version.shadow_merge_ref = pull_request.shadow_merge_ref
         version.merge_rev = pull_request.merge_rev
 
         version.revisions = pull_request.revisions
         version.pull_request = pull_request
         Session().add(version)
         Session().flush()
 
         return version
 
     def _generate_update_diffs(self, pull_request, pull_request_version):
         diff_context = (
             self.DIFF_CONTEXT +
             ChangesetCommentsModel.needed_extra_diff_context())
         old_diff = self._get_diff_from_pr_or_version(
             pull_request_version, context=diff_context)
         new_diff = self._get_diff_from_pr_or_version(
             pull_request, context=diff_context)
 
         old_diff_data = diffs.DiffProcessor(old_diff)
         old_diff_data.prepare()
         new_diff_data = diffs.DiffProcessor(new_diff)
         new_diff_data.prepare()
 
         return old_diff_data, new_diff_data
 
     def _link_comments_to_version(self, pull_request_version):
         """
         Link all unlinked comments of this pull request to the given version.
 
         :param pull_request_version: The `PullRequestVersion` to which
             the comments shall be linked.
 
         """
         pull_request = pull_request_version.pull_request
         comments = ChangesetComment.query().filter(
             # TODO: johbo: Should we query for the repo at all here?
             # Pending decision on how comments of PRs are to be related
             # to either the source repo, the target repo or no repo at all.
             ChangesetComment.repo_id == pull_request.target_repo.repo_id,
             ChangesetComment.pull_request == pull_request,
             ChangesetComment.pull_request_version == None)
 
         # TODO: johbo: Find out why this breaks if it is done in a bulk
         # operation.
         for comment in comments:
             comment.pull_request_version_id = (
                 pull_request_version.pull_request_version_id)
             Session().add(comment)
 
     def _calculate_commit_id_changes(self, old_ids, new_ids):
         added = new_ids.difference(old_ids)
         common = old_ids.intersection(new_ids)
         removed = old_ids.difference(new_ids)
         return ChangeTuple(added, common, removed)
 
     def _calculate_file_changes(self, old_diff_data, new_diff_data):
 
         old_files = OrderedDict()
         for diff_data in old_diff_data.parsed_diff:
             old_files[diff_data['filename']] = md5_safe(diff_data['raw_diff'])
 
         added_files = []
         modified_files = []
         removed_files = []
         for diff_data in new_diff_data.parsed_diff:
             new_filename = diff_data['filename']
             new_hash = md5_safe(diff_data['raw_diff'])
 
             old_hash = old_files.get(new_filename)
             if not old_hash:
                 # file is not present in old diff, means it's added
                 added_files.append(new_filename)
             else:
                 if new_hash != old_hash:
                     modified_files.append(new_filename)
                 # now remove a file from old, since we have seen it already
                 del old_files[new_filename]
 
         # removed files is when there are present in old, but not in NEW,
         # since we remove old files that are present in new diff, left-overs
         # if any should be the removed files
         removed_files.extend(old_files.keys())
 
         return FileChangeTuple(added_files, modified_files, removed_files)
 
     def _render_update_message(self, changes, file_changes):
         """
         render the message using DEFAULT_COMMENTS_RENDERER (RST renderer),
         so it's always looking the same disregarding on which default
         renderer system is using.
 
         :param changes: changes named tuple
         :param file_changes: file changes named tuple
 
         """
         new_status = ChangesetStatus.get_status_lbl(
             ChangesetStatus.STATUS_UNDER_REVIEW)
 
         changed_files = (
             file_changes.added + file_changes.modified + file_changes.removed)
 
         params = {
             'under_review_label': new_status,
             'added_commits': changes.added,
             'removed_commits': changes.removed,
             'changed_files': changed_files,
             'added_files': file_changes.added,
             'modified_files': file_changes.modified,
             'removed_files': file_changes.removed,
         }
         renderer = RstTemplateRenderer()
         return renderer.render('pull_request_update.mako', **params)
 
     def edit(self, pull_request, title, description):
         pull_request = self.__get_pull_request(pull_request)
         if pull_request.is_closed():
             raise ValueError('This pull request is closed')
         if title:
             pull_request.title = title
         pull_request.description = description
         pull_request.updated_on = datetime.datetime.now()
         Session().add(pull_request)
 
     def update_reviewers(self, pull_request, reviewer_data):
         """
         Update the reviewers in the pull request
 
         :param pull_request: the pr to update
         :param reviewer_data: list of tuples [(user, ['reason1', 'reason2'])]
         """
 
         reviewers_reasons = {}
         for user_id, reasons in reviewer_data:
             if isinstance(user_id, (int, basestring)):
                 user_id = self._get_user(user_id).user_id
             reviewers_reasons[user_id] = reasons
 
         reviewers_ids = set(reviewers_reasons.keys())
         pull_request = self.__get_pull_request(pull_request)
         current_reviewers = PullRequestReviewers.query()\
             .filter(PullRequestReviewers.pull_request ==
                     pull_request).all()
         current_reviewers_ids = set([x.user.user_id for x in current_reviewers])
 
         ids_to_add = reviewers_ids.difference(current_reviewers_ids)
         ids_to_remove = current_reviewers_ids.difference(reviewers_ids)
 
         log.debug("Adding %s reviewers", ids_to_add)
         log.debug("Removing %s reviewers", ids_to_remove)
         changed = False
         for uid in ids_to_add:
             changed = True
             _usr = self._get_user(uid)
             reasons = reviewers_reasons[uid]
             reviewer = PullRequestReviewers(_usr, pull_request, reasons)
             Session().add(reviewer)
 
         self.notify_reviewers(pull_request, ids_to_add)
 
         for uid in ids_to_remove:
             changed = True
             reviewer = PullRequestReviewers.query()\
                 .filter(PullRequestReviewers.user_id == uid,
                         PullRequestReviewers.pull_request == pull_request)\
                 .scalar()
             if reviewer:
                 Session().delete(reviewer)
         if changed:
             pull_request.updated_on = datetime.datetime.now()
             Session().add(pull_request)
 
         return ids_to_add, ids_to_remove
 
     def get_url(self, pull_request):
         return h.url('pullrequest_show',
                      repo_name=safe_str(pull_request.target_repo.repo_name),
                      pull_request_id=pull_request.pull_request_id,
                      qualified=True)
 
     def get_shadow_clone_url(self, pull_request):
         """
         Returns qualified url pointing to the shadow repository. If this pull
         request is closed there is no shadow repository and ``None`` will be
         returned.
         """
         if pull_request.is_closed():
             return None
         else:
             pr_url = urllib.unquote(self.get_url(pull_request))
             return safe_unicode('{pr_url}/repository'.format(pr_url=pr_url))
 
     def notify_reviewers(self, pull_request, reviewers_ids):
         # notification to reviewers
         if not reviewers_ids:
             return
 
         pull_request_obj = pull_request
         # get the current participants of this pull request
         recipients = reviewers_ids
         notification_type = EmailNotificationModel.TYPE_PULL_REQUEST
 
         pr_source_repo = pull_request_obj.source_repo
         pr_target_repo = pull_request_obj.target_repo
 
         pr_url = h.url(
             'pullrequest_show',
             repo_name=pr_target_repo.repo_name,
             pull_request_id=pull_request_obj.pull_request_id,
             qualified=True,)
 
         # set some variables for email notification
         pr_target_repo_url = h.url(
             'summary_home',
             repo_name=pr_target_repo.repo_name,
             qualified=True)
 
         pr_source_repo_url = h.url(
             'summary_home',
             repo_name=pr_source_repo.repo_name,
             qualified=True)
 
         # pull request specifics
         pull_request_commits = [
             (x.raw_id, x.message)
             for x in map(pr_source_repo.get_commit, pull_request.revisions)]
 
         kwargs = {
             'user': pull_request.author,
             'pull_request': pull_request_obj,
             'pull_request_commits': pull_request_commits,
 
             'pull_request_target_repo': pr_target_repo,
             'pull_request_target_repo_url': pr_target_repo_url,
 
             'pull_request_source_repo': pr_source_repo,
             'pull_request_source_repo_url': pr_source_repo_url,
 
             'pull_request_url': pr_url,
         }
 
         # pre-generate the subject for notification itself
         (subject,
          _h, _e,  # we don't care about those
          body_plaintext) = EmailNotificationModel().render_email(
             notification_type, **kwargs)
 
         # create notification objects, and emails
         NotificationModel().create(
             created_by=pull_request.author,
             notification_subject=subject,
             notification_body=body_plaintext,
             notification_type=notification_type,
             recipients=recipients,
             email_kwargs=kwargs,
         )
 
     def delete(self, pull_request):
         pull_request = self.__get_pull_request(pull_request)
         self._cleanup_merge_workspace(pull_request)
         Session().delete(pull_request)
 
     def close_pull_request(self, pull_request, user):
         pull_request = self.__get_pull_request(pull_request)
         self._cleanup_merge_workspace(pull_request)
         pull_request.status = PullRequest.STATUS_CLOSED
         pull_request.updated_on = datetime.datetime.now()
         Session().add(pull_request)
         self._trigger_pull_request_hook(
             pull_request, pull_request.author, 'close')
         self._log_action('user_closed_pull_request', user, pull_request)
 
     def close_pull_request_with_comment(self, pull_request, user, repo,
                                         message=None):
         status = ChangesetStatus.STATUS_REJECTED
 
         if not message:
             message = (
                 _('Status change %(transition_icon)s %(status)s') % {
                     'transition_icon': '>',
                     'status': ChangesetStatus.get_status_lbl(status)})
 
         internal_message = _('Closing with') + ' ' + message
 
         comm = ChangesetCommentsModel().create(
             text=internal_message,
             repo=repo.repo_id,
             user=user.user_id,
             pull_request=pull_request.pull_request_id,
             f_path=None,
             line_no=None,
             status_change=ChangesetStatus.get_status_lbl(status),
             status_change_type=status,
             closing_pr=True
         )
 
         ChangesetStatusModel().set_status(
             repo.repo_id,
             status,
             user.user_id,
             comm,
             pull_request=pull_request.pull_request_id
         )
         Session().flush()
 
         PullRequestModel().close_pull_request(
             pull_request.pull_request_id, user)
 
     def merge_status(self, pull_request):
         if not self._is_merge_enabled(pull_request):
             return False, _('Server-side pull request merging is disabled.')
         if pull_request.is_closed():
             return False, _('This pull request is closed.')
         merge_possible, msg = self._check_repo_requirements(
             target=pull_request.target_repo, source=pull_request.source_repo)
         if not merge_possible:
             return merge_possible, msg
 
         try:
             resp = self._try_merge(pull_request)
             log.debug("Merge response: %s", resp)
             status = resp.possible, self.merge_status_message(
                 resp.failure_reason)
         except NotImplementedError:
             status = False, _('Pull request merging is not supported.')
 
         return status
 
     def _check_repo_requirements(self, target, source):
         """
         Check if `target` and `source` have compatible requirements.
 
         Currently this is just checking for largefiles.
         """
         target_has_largefiles = self._has_largefiles(target)
         source_has_largefiles = self._has_largefiles(source)
         merge_possible = True
         message = u''
 
         if target_has_largefiles != source_has_largefiles:
             merge_possible = False
             if source_has_largefiles:
                 message = _(
                     'Target repository large files support is disabled.')
             else:
                 message = _(
                     'Source repository large files support is disabled.')
 
         return merge_possible, message
 
     def _has_largefiles(self, repo):
         largefiles_ui = VcsSettingsModel(repo=repo).get_ui_settings(
             'extensions', 'largefiles')
         return largefiles_ui and largefiles_ui[0].active
 
     def _try_merge(self, pull_request):
         """
         Try to merge the pull request and return the merge status.
         """
         log.debug(
             "Trying out if the pull request %s can be merged.",
             pull_request.pull_request_id)
         target_vcs = pull_request.target_repo.scm_instance()
 
         # Refresh the target reference.
         try:
             target_ref = self._refresh_reference(
                 pull_request.target_ref_parts, target_vcs)
         except CommitDoesNotExistError:
             merge_state = MergeResponse(
                 False, False, None, MergeFailureReason.MISSING_TARGET_REF)
             return merge_state
 
         target_locked = pull_request.target_repo.locked
         if target_locked and target_locked[0]:
             log.debug("The target repository is locked.")
             merge_state = MergeResponse(
                 False, False, None, MergeFailureReason.TARGET_IS_LOCKED)
         elif self._needs_merge_state_refresh(pull_request, target_ref):
             log.debug("Refreshing the merge status of the repository.")
             merge_state = self._refresh_merge_state(
                 pull_request, target_vcs, target_ref)
         else:
             possible = pull_request.\
                 _last_merge_status == MergeFailureReason.NONE
             merge_state = MergeResponse(
                 possible, False, None, pull_request._last_merge_status)
 
         return merge_state
 
     def _refresh_reference(self, reference, vcs_repository):
         if reference.type in ('branch', 'book'):
             name_or_id = reference.name
         else:
             name_or_id = reference.commit_id
         refreshed_commit = vcs_repository.get_commit(name_or_id)
         refreshed_reference = Reference(
             reference.type, reference.name, refreshed_commit.raw_id)
         return refreshed_reference
 
     def _needs_merge_state_refresh(self, pull_request, target_reference):
         return not(
             pull_request.revisions and
             pull_request.revisions[0] == pull_request._last_merge_source_rev and
             target_reference.commit_id == pull_request._last_merge_target_rev)
 
     def _refresh_merge_state(self, pull_request, target_vcs, target_reference):
         workspace_id = self._workspace_id(pull_request)
         source_vcs = pull_request.source_repo.scm_instance()
         use_rebase = self._use_rebase_for_merging(pull_request)
         merge_state = target_vcs.merge(
             target_reference, source_vcs, pull_request.source_ref_parts,
             workspace_id, dry_run=True, use_rebase=use_rebase)
 
         # Do not store the response if there was an unknown error.
         if merge_state.failure_reason != MergeFailureReason.UNKNOWN:
             pull_request._last_merge_source_rev = \
                 pull_request.source_ref_parts.commit_id
             pull_request._last_merge_target_rev = target_reference.commit_id
             pull_request._last_merge_status = merge_state.failure_reason
             pull_request.shadow_merge_ref = merge_state.merge_ref
             Session().add(pull_request)
             Session().commit()
 
         return merge_state
 
     def _workspace_id(self, pull_request):
         workspace_id = 'pr-%s' % pull_request.pull_request_id
         return workspace_id
 
     def merge_status_message(self, status_code):
         """
         Return a human friendly error message for the given merge status code.
         """
         return self.MERGE_STATUS_MESSAGES[status_code]
 
     def generate_repo_data(self, repo, commit_id=None, branch=None,
                            bookmark=None):
         all_refs, selected_ref = \
             self._get_repo_pullrequest_sources(
                 repo.scm_instance(), commit_id=commit_id,
                 branch=branch, bookmark=bookmark)
 
         refs_select2 = []
         for element in all_refs:
             children = [{'id': x[0], 'text': x[1]} for x in element[0]]
             refs_select2.append({'text': element[1], 'children': children})
 
         return {
             'user': {
                 'user_id': repo.user.user_id,
                 'username': repo.user.username,
                 'firstname': repo.user.firstname,
                 'lastname': repo.user.lastname,
                 'gravatar_link': h.gravatar_url(repo.user.email, 14),
             },
             'description': h.chop_at_smart(repo.description, '\n'),
             'refs': {
                 'all_refs': all_refs,
                 'selected_ref': selected_ref,
                 'select2_refs': refs_select2
             }
         }
 
     def generate_pullrequest_title(self, source, source_ref, target):
         return u'{source}#{at_ref} to {target}'.format(
             source=source,
             at_ref=source_ref,
             target=target,
         )
 
     def _cleanup_merge_workspace(self, pull_request):
         # Merging related cleanup
         target_scm = pull_request.target_repo.scm_instance()
         workspace_id = 'pr-%s' % pull_request.pull_request_id
 
         try:
             target_scm.cleanup_merge_workspace(workspace_id)
         except NotImplementedError:
             pass
 
     def _get_repo_pullrequest_sources(
             self, repo, commit_id=None, branch=None, bookmark=None):
         """
         Return a structure with repo's interesting commits, suitable for
         the selectors in pullrequest controller
 
         :param commit_id: a commit that must be in the list somehow
             and selected by default
         :param branch: a branch that must be in the list and selected
             by default - even if closed
         :param bookmark: a bookmark that must be in the list and selected
         """
 
         commit_id = safe_str(commit_id) if commit_id else None
         branch = safe_str(branch) if branch else None
         bookmark = safe_str(bookmark) if bookmark else None
 
         selected = None
 
         # order matters: first source that has commit_id in it will be selected
         sources = []
         sources.append(('book', repo.bookmarks.items(), _('Bookmarks'), bookmark))
         sources.append(('branch', repo.branches.items(), _('Branches'), branch))
 
         if commit_id:
             ref_commit = (h.short_id(commit_id), commit_id)
             sources.append(('rev', [ref_commit], _('Commit IDs'), commit_id))
 
         sources.append(
             ('branch', repo.branches_closed.items(), _('Closed Branches'), branch),
         )
 
         groups = []
         for group_key, ref_list, group_name, match in sources:
             group_refs = []
             for ref_name, ref_id in ref_list:
                 ref_key = '%s:%s:%s' % (group_key, ref_name, ref_id)
                 group_refs.append((ref_key, ref_name))
 
                 if not selected:
                     if set([commit_id, match]) & set([ref_id, ref_name]):
                         selected = ref_key
 
             if group_refs:
                 groups.append((group_refs, group_name))
 
         if not selected:
             ref = commit_id or branch or bookmark
             if ref:
                 raise CommitDoesNotExistError(
                     'No commit refs could be found matching: %s' % ref)
             elif repo.DEFAULT_BRANCH_NAME in repo.branches:
                 selected = 'branch:%s:%s' % (
                     repo.DEFAULT_BRANCH_NAME,
                     repo.branches[repo.DEFAULT_BRANCH_NAME]
                 )
             elif repo.commit_ids:
                 rev = repo.commit_ids[0]
                 selected = 'rev:%s:%s' % (rev, rev)
             else:
                 raise EmptyRepositoryError()
         return groups, selected
 
     def get_diff(self, pull_request, context=DIFF_CONTEXT):
         pull_request = self.__get_pull_request(pull_request)
         return self._get_diff_from_pr_or_version(pull_request, context=context)
 
     def _get_diff_from_pr_or_version(self, pr_or_version, context):
         source_repo = pr_or_version.source_repo
 
         # we swap org/other ref since we run a simple diff on one repo
         target_ref_id = pr_or_version.target_ref_parts.commit_id
         source_ref_id = pr_or_version.source_ref_parts.commit_id
         target_commit = source_repo.get_commit(
             commit_id=safe_str(target_ref_id))
         source_commit = source_repo.get_commit(commit_id=safe_str(source_ref_id))
         vcs_repo = source_repo.scm_instance()
 
         # TODO: johbo: In the context of an update, we cannot reach
         # the old commit anymore with our normal mechanisms. It needs
         # some sort of special support in the vcs layer to avoid this
         # workaround.
         if (source_commit.raw_id == vcs_repo.EMPTY_COMMIT_ID and
                 vcs_repo.alias == 'git'):
             source_commit.raw_id = safe_str(source_ref_id)
 
         log.debug('calculating diff between '
                   'source_ref:%s and target_ref:%s for repo `%s`',
                   target_ref_id, source_ref_id,
                   safe_unicode(vcs_repo.path))
 
         vcs_diff = vcs_repo.get_diff(
             commit1=target_commit, commit2=source_commit, context=context)
         return vcs_diff
 
     def _is_merge_enabled(self, pull_request):
         settings_model = VcsSettingsModel(repo=pull_request.target_repo)
         settings = settings_model.get_general_settings()
         return settings.get('rhodecode_pr_merge_enabled', False)
 
     def _use_rebase_for_merging(self, pull_request):
         settings_model = VcsSettingsModel(repo=pull_request.target_repo)
         settings = settings_model.get_general_settings()
         return settings.get('rhodecode_hg_use_rebase_for_merging', False)
 
     def _log_action(self, action, user, pull_request):
         action_logger(
             user,
             '{action}:{pr_id}'.format(
                 action=action, pr_id=pull_request.pull_request_id),
             pull_request.target_repo)
 
 
 ChangeTuple = namedtuple('ChangeTuple',
                          ['added', 'common', 'removed'])
 
 FileChangeTuple = namedtuple('FileChangeTuple',
                              ['added', 'modified', 'removed'])