Merge branch 'jprovazn-rebase-ee' into 'master'

Backport 'Rebase' feature from EE to CE

See merge request gitlab-org/gitlab-ee!3890

ee/app/assets/javascripts/vue_merge_request_widget/components/states/mr_widget_rebase.vue → app/assets/javascripts/vue_merge_request_widget/components/states/mr_widget_rebase.vue

 <script>
-  import simplePoll from '~/lib/utils/simple_poll';
-  import eventHub from '~/vue_merge_request_widget/event_hub';
-  import statusIcon from '~/vue_merge_request_widget/components/mr_widget_status_icon';
-  import loadingIcon from '~/vue_shared/components/loading_icon.vue';
-  import Flash from '~/flash';
+  import simplePoll from '../../../lib/utils/simple_poll';
+  import eventHub from '../../event_hub';
+  import statusIcon from '../mr_widget_status_icon';
+  import loadingIcon from '../../../vue_shared/components/loading_icon.vue';
+  import Flash from '../../../flash';
 
   export default {
+    name: 'MRWidgetRebase',
     props: {
       mr: {
         type: Object,

app/assets/javascripts/vue_merge_request_widget/dependencies.js

@@ -32,6 +32,7 @@ export { default as UnresolvedDiscussionsState } from './components/states/mr_wi
 export { default as PipelineBlockedState } from './components/states/mr_widget_pipeline_blocked';
 export { default as PipelineFailedState } from './components/states/mr_widget_pipeline_failed';
 export { default as MergeWhenPipelineSucceedsState } from './components/states/mr_widget_merge_when_pipeline_succeeds';
+export { default as RebaseState } from './components/states/mr_widget_rebase.vue';
 export { default as AutoMergeFailed } from './components/states/mr_widget_auto_merge_failed';
 export { default as CheckingState } from './components/states/mr_widget_checking';
 export { default as MRWidgetStore } from 'ee/vue_merge_request_widget/stores/mr_widget_store';

app/assets/javascripts/vue_merge_request_widget/mr_widget_options.js

@@ -10,6 +10,7 @@ import {
   MergedState,
   ClosedState,
   MergingState,
+  RebaseState,
   WipState,
   ArchivedState,
   ConflictsState,
@@ -230,6 +231,7 @@ export default {
     'mr-widget-pipeline-failed': PipelineFailedState,
     'mr-widget-merge-when-pipeline-succeeds': MergeWhenPipelineSucceedsState,
     'mr-widget-auto-merge-failed': AutoMergeFailed,
+    'mr-widget-rebase': RebaseState,
   },
   template: `
     <div class="mr-state-widget prepend-top-default">

app/assets/javascripts/vue_merge_request_widget/services/mr_widget_service.js

@@ -37,6 +37,10 @@ export default class MRWidgetService {
     return axios.get(this.endpoints.mergeActionsContentPath);
   }
 
+  rebase() {
+    return axios.post(this.endpoints.rebasePath);
+  }
+
   static stopEnvironment(url) {
     return axios.post(url);
   }

app/assets/javascripts/vue_merge_request_widget/stores/get_state_key.js

@@ -25,6 +25,8 @@ export default function deviseState(data) {
     return this.mergeError ? stateKey.autoMergeFailed : stateKey.mergeWhenPipelineSucceeds;
   } else if (!this.canMerge) {
     return stateKey.notAllowedToMerge;
+  } else if (this.shouldBeRebased) {
+    return stateKey.rebase;
   } else if (this.canBeMerged) {
     return stateKey.readyToMerge;
   }

app/assets/javascripts/vue_merge_request_widget/stores/mr_widget_store.js

@@ -28,6 +28,7 @@ export default class MergeRequestStore {
     this.divergedCommitsCount = data.diverged_commits_count;
     this.pipeline = data.pipeline || {};
     this.deployments = this.deployments || data.deployments || [];
+    this.initRebase(data);
 
     if (data.issues_links) {
       const links = data.issues_links;
@@ -126,6 +127,13 @@ export default class MergeRequestStore {
     return this.state === stateKey.nothingToMerge;
   }
 
+  initRebase(data) {
+    this.canPushToSourceBranch = data.can_push_to_source_branch;
+    this.rebaseInProgress = data.rebase_in_progress;
+    this.approvalsLeft = !data.approved;
+    this.rebasePath = data.rebase_path;
+  }
+
   static buildMetrics(metrics) {
     if (!metrics) {
       return {};

app/assets/javascripts/vue_merge_request_widget/stores/state_maps.js

@@ -17,6 +17,7 @@ const stateToComponentMap = {
   failedToMerge: 'mr-widget-failed-to-merge',
   autoMergeFailed: 'mr-widget-auto-merge-failed',
   shaMismatch: 'mr-widget-sha-mismatch',
+  rebase: 'mr-widget-rebase',
 };
 
 const statesToShowHelpWidget = [
@@ -29,6 +30,7 @@ const statesToShowHelpWidget = [
   'pipelineFailed',
   'pipelineBlocked',
   'autoMergeFailed',
+  'rebase',
 ];
 
 export const stateKey = {
@@ -46,6 +48,7 @@ export const stateKey = {
   mergeWhenPipelineSucceeds: 'mergeWhenPipelineSucceeds',
   notAllowedToMerge: 'notAllowedToMerge',
   readyToMerge: 'readyToMerge',
+  rebase: 'rebase',
 };
 
 export default {

app/controllers/projects/merge_requests_controller.rb

@@ -12,6 +12,7 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
   before_action :authorize_update_issuable!, only: [:close, :edit, :update, :remove_wip, :sort]
   before_action :set_issuables_index, only: [:index]
   before_action :authenticate_user!, only: [:assign_related_issues]
+  before_action :check_user_can_push_to_source_branch!, only: [:rebase]
 
   def index
     @merge_requests = @issuables
@@ -226,6 +227,12 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
     render json: environments
   end
 
+  def rebase
+    RebaseWorker.perform_async(@merge_request.id, current_user.id)
+
+    render nothing: true, status: 200
+  end
+
   protected
 
   alias_method :subscribable_resource, :merge_request
@@ -331,4 +338,14 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
     @finder_type = MergeRequestsFinder
     super
   end
+
+  def check_user_can_push_to_source_branch!
+    return access_denied! unless @merge_request.source_branch_exists?
+
+    access_check = ::Gitlab::UserAccess
+      .new(current_user, project: @merge_request.source_project)
+      .can_push_to_branch?(@merge_request.source_branch)
+
+    access_denied! unless access_check
+  end
 end

app/models/merge_request.rb

@@ -161,6 +161,13 @@ class MergeRequest < ActiveRecord::Base
     '!'
   end
 
+  def rebase_in_progress?
+    # The source project can be deleted
+    return false unless source_project
+
+    source_project.repository.rebase_in_progress?(id)
+  end
+
   # Use this method whenever you need to make sure the head_pipeline is synced with the
   # branch head commit, for example checking if a merge request can be merged.
   # For more information check: https://gitlab.com/gitlab-org/gitlab-ce/issues/40004

app/models/repository.rb

@@ -1154,6 +1154,13 @@ class Repository
     @project.repository_storage_path
   end
 
+  def rebase(user, merge_request)
+    raw.rebase(user, merge_request.id, branch: merge_request.source_branch,
+                                       branch_sha: merge_request.source_branch_sha,
+                                       remote_repository: merge_request.target_project.repository.raw,
+                                       remote_branch: merge_request.target_branch)
+  end
+
   private
 
   # TODO Generice finder, later split this on finders by Ref or Oid

app/serializers/merge_request_widget_entity.rb

@@ -22,6 +22,7 @@ class MergeRequestWidgetEntity < IssuableEntity
   # EE-specific
   expose :approvals_before_merge
   expose :squash
+
   expose :rebase_commit_sha
   expose :rebase_in_progress?, as: :rebase_in_progress
 

app/views/projects/_merge_request_fast_forward_settings.html.haml

@@ -10,4 +10,4 @@
       No merge commits are created and all merges are fast-forwarded, which means that merging is only allowed if the branch could be fast-forwarded.
     %br
     %span.descr
-      When fast-forward merge is not possible, the user must first rebase locally.
+      When fast-forward merge is not possible, the user is given the option to rebase.

app/views/projects/_merge_request_rebase_settings.html.haml

@@ -10,4 +10,4 @@
       This way you could make sure that if this merge request would build, after merging to target branch it would also build.
     %br
     %span.descr
-      When fast-forward merge is not possible, the user must first rebase locally.
+      When fast-forward merge is not possible, the user is given the option to rebase.

app/workers/all_queues.yml

@@ -89,6 +89,7 @@
 - project_service
 - propagate_service_template
 - reactive_caching
+- rebase
 - repository_fork
 - repository_import
 - storage_migrator

config/routes/project.rb

@@ -105,6 +105,7 @@ constraints(ProjectUrlConstrainer.new) do
 
           post :remove_wip
           post :assign_related_issues
+          post :rebase
 
           scope constraints: { format: nil }, action: :show do
             get :commits, defaults: { tab: 'commits' }

ee/app/assets/javascripts/vue_merge_request_widget/mr_widget_options.js

@@ -2,7 +2,6 @@ import { n__, s__, sprintf } from '~/locale';
 import CEWidgetOptions from '~/vue_merge_request_widget/mr_widget_options';
 import WidgetApprovals from './components/approvals/mr_widget_approvals';
 import GeoSecondaryNode from './components/states/mr_widget_secondary_geo_node';
-import RebaseState from './components/states/mr_widget_rebase.vue';
 import collapsibleSection from './components/mr_widget_report_collapsible_section.vue';
 
 export default {
@@ -10,7 +9,6 @@ export default {
   components: {
     'mr-widget-approvals': WidgetApprovals,
     'mr-widget-geo-secondary-node': GeoSecondaryNode,
-    'mr-widget-rebase': RebaseState,
     collapsibleSection,
   },
   data() {

ee/app/assets/javascripts/vue_merge_request_widget/services/mr_widget_service.js

@@ -7,7 +7,6 @@ export default class MRWidgetService extends CEWidgetService {
     super(mr);
 
     this.approvalsPath = mr.approvalsPath;
-    this.rebasePath = mr.rebasePath;
   }
 
   fetchApprovals() {
@@ -25,10 +24,6 @@ export default class MRWidgetService extends CEWidgetService {
       .then(res => res.data);
   }
 
-  rebase() {
-    return axios.post(this.rebasePath);
-  }
-
   fetchReport(endpoint) { // eslint-disable-line
     return axios.get(endpoint)
       .then(res => res.data);

ee/app/assets/javascripts/vue_merge_request_widget/stores/get_state_key.js

@@ -5,10 +5,6 @@ export default function (data) {
     return 'geoSecondaryNode';
   }
 
-  if (this.shouldBeRebased) {
-    return 'rebase';
-  }
-
   return CEGetStateKey.call(this, data);
 }
 

ee/app/assets/javascripts/vue_merge_request_widget/stores/mr_widget_store.js

@@ -14,7 +14,6 @@ export default class MergeRequestStore extends CEMergeRequestStore {
   setData(data) {
     this.initGeo(data);
     this.initSquashBeforeMerge(data);
-    this.initRebase(data);
     this.initApprovals(data);
 
     super.setData(data);
@@ -27,13 +26,6 @@ export default class MergeRequestStore extends CEMergeRequestStore {
       || data.enable_squash_before_merge;
   }
 
-  initRebase(data) {
-    this.canPushToSourceBranch = data.can_push_to_source_branch;
-    this.rebaseInProgress = data.rebase_in_progress;
-    this.approvalsLeft = !data.approved;
-    this.rebasePath = data.rebase_path;
-  }
-
   initGeo(data) {
     this.isGeoSecondaryNode = this.isGeoSecondaryNode || data.is_geo_secondary_node;
     this.geoSecondaryHelpPath = this.geoSecondaryHelpPath || data.geo_secondary_help_path;

ee/app/assets/javascripts/vue_merge_request_widget/stores/state_maps.js

 import stateMaps from '~/vue_merge_request_widget/stores/state_maps';
 
 stateMaps.stateToComponentMap.geoSecondaryNode = 'mr-widget-geo-secondary-node';
-stateMaps.stateToComponentMap.rebase = 'mr-widget-rebase';
-stateMaps.statesToShowHelpWidget.push('rebase');
 
 export default {
   stateToComponentMap: stateMaps.stateToComponentMap,

ee/app/controllers/ee/projects/merge_requests_controller.rb

@@ -3,17 +3,6 @@ module EE
     module MergeRequestsController
       extend ActiveSupport::Concern
 
-      prepended do
-        before_action :check_merge_request_rebase_available!, only: [:rebase]
-        before_action :check_user_can_push_to_source_branch!, only: [:rebase]
-      end
-
-      def rebase
-        RebaseWorker.perform_async(merge_request.id, current_user.id)
-
-        render nothing: true, status: 200
-      end
-
       def approve
         unless merge_request.can_approve?(current_user)
           return render_404
@@ -63,16 +52,6 @@ module EE
 
         attrs
       end
-
-      def check_user_can_push_to_source_branch!
-        return access_denied! unless merge_request.source_branch_exists?
-
-        access_check = ::Gitlab::UserAccess
-          .new(current_user, project: merge_request.source_project)
-          .can_push_to_branch?(merge_request.source_branch)
-
-        access_denied! unless access_check
-      end
     end
   end
 end

ee/app/models/ee/merge_request.rb

@@ -20,13 +20,6 @@ module EE
       delegate :sha, to: :base_pipeline, prefix: :base_pipeline, allow_nil: true
     end
 
-    def rebase_in_progress?
-      # The source project can be deleted
-      return false unless source_project
-
-      source_project.repository.rebase_in_progress?(id)
-    end
-
     def squash_in_progress?
       # The source project can be deleted
       return false unless source_project

ee/app/models/ee/project.rb

@@ -419,11 +419,6 @@ module EE
       super unless mirror?
     end
 
-    def merge_requests_rebase_enabled
-      super && feature_available?(:merge_request_rebase)
-    end
-    alias_method :merge_requests_rebase_enabled?, :merge_requests_rebase_enabled
-
     def merge_requests_ff_only_enabled
       super
     end

ee/app/models/ee/repository.rb

@@ -31,13 +31,6 @@ module EE
       refs.map { |sha| commit(sha.strip) }
     end
 
-    def rebase(user, merge_request)
-      raw.rebase(user, merge_request.id, branch: merge_request.source_branch,
-                                         branch_sha: merge_request.source_branch_sha,
-                                         remote_repository: merge_request.target_project.repository.raw,
-                                         remote_branch: merge_request.target_branch)
-    end
-
     def squash(user, merge_request)
       raw.squash(user, merge_request.id, branch: merge_request.target_branch,
                                          start_sha: merge_request.diff_start_sha,

ee/app/models/license.rb

@@ -19,7 +19,6 @@ class License < ActiveRecord::Base
     jenkins_integration
     ldap_group_sync
     merge_request_approvers
-    merge_request_rebase
     merge_request_squash
     multiple_ldap_servers
     multiple_issue_assignees
@@ -80,7 +79,6 @@ class License < ActiveRecord::Base
     issue_weights
     jenkins_integration
     merge_request_approvers
-    merge_request_rebase
     merge_request_squash
     multiple_issue_assignees
     multiple_issue_boards

ee/app/views/projects/ee/_merge_request_fast_forward_settings.html.haml

-- form = local_assigns.fetch(:form)
-- project = local_assigns.fetch(:project)
-
-.radio
-  = label_tag :project_merge_method_ff do
-    = form.radio_button :merge_method, :ff, class: "js-merge-method-radio"
-    %strong Fast-forward merge
-    %br
-    %span.descr
-      No merge commits are created and all merges are fast-forwarded, which means that merging is only allowed if the branch could be fast-forwarded.
-    - if project.feature_available?(:merge_request_rebase)
-      %br
-      %span.descr
-        When fast-forward merge is not possible, the user is given the option to rebase.

ee/app/views/projects/ee/_merge_request_rebase_settings.html.haml

-- form = local_assigns.fetch(:form)
-
-.radio
-  = label_tag :project_merge_method_rebase_merge do
-    = form.radio_button :merge_method, :rebase_merge, class: "js-merge-method-radio"
-    %strong Merge commit with semi-linear history
-    %br
-    %span.descr
-      A merge commit is created for every merge, but merging is only allowed if fast-forward merge is possible.
-      This way you could make sure that if this merge request would build, after merging to target branch it would also build.
-    %br
-    %span.descr
-      When fast-forward merge is not possible, the user is given the option to rebase.

ee/app/views/projects/ee/_merge_request_settings.html.haml

@@ -11,9 +11,9 @@
       %span.descr
         A merge commit is created for every merge, and merging is allowed as long as there are no conflicts.
 
-  = render 'projects/ee/merge_request_rebase_settings', form: form
+  = render 'projects/merge_request_rebase_settings', form: form
 
-  = render 'projects/ee/merge_request_fast_forward_settings', project: @project, form: form
+  = render 'projects/merge_request_fast_forward_settings', project: @project, form: form
 
 
 - if @project.feature_available?(:issuable_default_templates)

spec/controllers/projects/merge_requests_controller_spec.rb

@@ -685,4 +685,62 @@ describe Projects::MergeRequestsController do
                             format: :json
     end
   end
+
+  describe 'POST #rebase' do
+    let(:viewer)        { user }
+
+    def post_rebase
+      post :rebase, namespace_id: project.namespace, project_id: project, id: merge_request
+    end
+
+    def expect_rebase_worker_for(user)
+      expect(RebaseWorker).to receive(:perform_async).with(merge_request.id, user.id)
+    end
+
+    context 'successfully' do
+      it 'enqeues a RebaseWorker' do
+        expect_rebase_worker_for(viewer)
+
+        post_rebase
+
+        expect(response.status).to eq(200)
+      end
+    end
+
+    context 'with a forked project' do
+      let(:fork_project) { create(:project, :repository, forked_from_project: project) }
+      let(:fork_owner) { fork_project.owner }
+
+      before do
+        merge_request.update!(source_project: fork_project)
+        fork_project.add_reporter(user)
+      end
+
+      context 'user cannot push to source branch' do
+        it 'returns 404' do
+          expect_rebase_worker_for(viewer).never
+
+          post_rebase
+
+          expect(response.status).to eq(404)
+        end
+      end
+
+      context 'user can push to source branch' do
+        before do
+          project.add_reporter(fork_owner)
+
+          sign_in(fork_owner)
+        end
+
+        it 'returns 200' do
+          expect_rebase_worker_for(fork_owner)
+
+          post_rebase
+
+          expect(response.status).to eq(200)
+        end
+      end
+    end
+  end
 end

spec/ee/spec/controllers/projects/merge_requests_controller_spec.rb

@@ -367,16 +367,6 @@ describe Projects::MergeRequestsController do
       expect(RebaseWorker).to receive(:perform_async).with(merge_request.id, user.id)
     end
 
-    context 'successfully' do
-      it 'enqeues a RebaseWorker' do
-        expect_rebase_worker_for(viewer)
-
-        post_rebase
-
-        expect(response.status).to eq(200)
-      end
-    end
-
     context 'approvals pending' do
       let(:project) { create(:project, :repository, approvals_before_merge: 1) }
 
@@ -399,43 +389,6 @@ describe Projects::MergeRequestsController do
       end
 
       it_behaves_like 'approvals'
-
-      context 'user cannot push to source branch' do
-        it 'returns 404' do
-          expect_rebase_worker_for(viewer).never
-
-          post_rebase
-
-          expect(response.status).to eq(404)
-        end
-      end
-
-      context 'user can push to source branch' do
-        before do
-          project.add_reporter(fork_owner)
-
-          sign_in(fork_owner)
-        end
-
-        it 'returns 200' do
-          expect_rebase_worker_for(fork_owner)
-
-          post_rebase
-
-          expect(response.status).to eq(200)
-        end
-      end
-    end
-
-    context 'rebase unavailable in license' do
-      it 'returns 404' do
-        stub_licensed_features(merge_request_rebase: false)
-        expect_rebase_worker_for(viewer).never
-
-        post_rebase
-
-        expect(response.status).to eq(404)
-      end
     end
   end
 end

spec/ee/spec/models/ee/merge_request_spec.rb

@@ -13,66 +13,6 @@ describe MergeRequest do
     it { is_expected.to have_many(:approver_groups).dependent(:delete_all) }
   end
 
-  describe '#should_be_rebased?' do
-    subject { merge_request.should_be_rebased? }
-
-    context 'project forbids rebase' do
-      it { is_expected.to be_falsy }
-    end
-
-    context 'project allows rebase' do
-      let(:project) { create(:project, :repository, merge_requests_rebase_enabled: true) }
-
-      it 'returns false when the project feature is unavailable' do
-        expect(merge_request.target_project).to receive(:feature_available?).with(:merge_request_rebase).at_least(:once).and_return(false)
-
-        is_expected.to be_falsy
-      end
-
-      it 'returns true when the project feature is available' do
-        expect(merge_request.target_project).to receive(:feature_available?).with(:merge_request_rebase).at_least(:once).and_return(true)
-
-        is_expected.to be_truthy
-      end
-    end
-  end
-
-  describe '#rebase_in_progress?' do
-    # Create merge request and project before we stub file calls
-    before do
-      subject
-    end
-
-    it 'returns true when there is a current rebase directory' do
-      allow(File).to receive(:exist?).and_return(true)
-      allow(File).to receive(:mtime).and_return(Time.now)
-
-      expect(subject.rebase_in_progress?).to be_truthy
-    end
-
-    it 'returns false when there is no rebase directory' do
-      allow(File).to receive(:exist?).and_return(false)
-
-      expect(subject.rebase_in_progress?).to be_falsey
-    end
-
-    it 'returns false when the rebase directory has expired' do
-      allow(File).to receive(:exist?).and_return(true)
-      allow(File).to receive(:mtime).and_return(20.minutes.ago)
-
-      expect(subject.rebase_in_progress?).to be_falsey
-    end
-
-    it 'returns false when the source project has been removed' do
-      allow(subject).to receive(:source_project).and_return(nil)
-      allow(File).to receive(:exist?).and_return(true)
-      allow(File).to receive(:mtime).and_return(Time.now)
-
-      expect(File).not_to have_received(:exist?)
-      expect(subject.rebase_in_progress?).to be_falsey
-    end
-  end
-
   describe '#squash_in_progress?' do
     # Create merge request and project before we stub file calls
     before do

spec/ee/spec/models/ee/project_spec.rb

@@ -1066,31 +1066,6 @@ describe Project do
     end
   end
 
-  describe '#merge_method' do
-    where(:ff, :rebase, :rebase_licensed, :method) do
-      true  | true  | true  | :ff
-      true  | true  | false | :ff
-      true  | false | true  | :ff
-      true  | false | false | :ff
-      false | true  | true  | :rebase_merge
-      false | true  | false | :merge
-      false | false | true  | :merge
-      false | false | false | :merge
-    end
-
-    with_them do
-      let(:project) { build(:project, merge_requests_rebase_enabled: rebase, merge_requests_ff_only_enabled: ff) }
-
-      subject { project.merge_method }
-
-      before do
-        stub_licensed_features(merge_request_rebase: rebase_licensed)
-      end
-
-      it { is_expected.to eq(method) }
-    end
-  end
-
   describe '#rename_repo' do
     context 'when running on a primary node' do
       set(:primary) { create(:geo_node, :primary) }

spec/fixtures/api/schemas/entities/merge_request_widget.json

@@ -105,14 +105,14 @@
     "merge_ongoing": { "type": "boolean" },
     "ff_only_enabled": { "type": ["boolean", false] },
     "should_be_rebased": { "type": "boolean" },
-
-    // EE-specific
     "rebase_commit_sha": { "type": ["string", "null"] },
-    "approvals_before_merge": { "type": ["integer", "null"] },
-    "squash": { "type": "boolean" },
     "rebase_in_progress": { "type": "boolean" },
     "can_push_to_source_branch": { "type": "boolean" },
     "rebase_path": { "type": ["string", "null"] },
+
+    // EE-specific
+    "approvals_before_merge": { "type": ["integer", "null"] },
+    "squash": { "type": "boolean" },
     "approved": { "type": "boolean" },
     "approvals_path": { "type": ["string", "null"] },
     "codeclimate": {

spec/javascripts/vue_mr_widget/components/mr_widget_rebase_spec.js

 import Vue from 'vue';
 import eventHub from '~/vue_merge_request_widget/event_hub';
-import component from 'ee/vue_merge_request_widget/components/states/mr_widget_rebase.vue';
+import component from '~/vue_merge_request_widget/components/states/mr_widget_rebase.vue';
 import mountComponent from '../../helpers/vue_mount_component_helper';
 
 describe('Merge request widget rebase component', () => {

spec/models/merge_request_spec.rb

@@ -2346,4 +2346,50 @@ describe MergeRequest do
       end
     end
   end
+
+  describe '#should_be_rebased?' do
+    let(:project) { create(:project, :repository) }
+
+    it 'returns false for the same source and target branches' do
+      merge_request = create(:merge_request, source_project: project, target_project: project)
+
+      expect(merge_request.should_be_rebased?).to be_falsey
+    end
+  end
+
+  describe '#rebase_in_progress?' do
+    # Create merge request and project before we stub file calls
+    before do
+      subject
+    end
+
+    it 'returns true when there is a current rebase directory' do
+      allow(File).to receive(:exist?).and_return(true)
+      allow(File).to receive(:mtime).and_return(Time.now)
+
+      expect(subject.rebase_in_progress?).to be_truthy
+    end
+
+    it 'returns false when there is no rebase directory' do
+      allow(File).to receive(:exist?).and_return(false)
+
+      expect(subject.rebase_in_progress?).to be_falsey
+    end
+
+    it 'returns false when the rebase directory has expired' do
+      allow(File).to receive(:exist?).and_return(true)
+      allow(File).to receive(:mtime).and_return(20.minutes.ago)
+
+      expect(subject.rebase_in_progress?).to be_falsey
+    end
+
+    it 'returns false when the source project has been removed' do
+      allow(subject).to receive(:source_project).and_return(nil)
+      allow(File).to receive(:exist?).and_return(true)
+      allow(File).to receive(:mtime).and_return(Time.now)
+
+      expect(File).not_to have_received(:exist?)
+      expect(subject.rebase_in_progress?).to be_falsey
+    end
+  end
 end

spec/models/project_spec.rb

@@ -456,14 +456,21 @@ describe Project do
   end
 
   describe '#merge_method' do
-    it 'returns "ff" merge_method when ff is enabled' do
-      project = build(:project, merge_requests_ff_only_enabled: true)
-      expect(project.merge_method).to be :ff
+    using RSpec::Parameterized::TableSyntax
+
+    where(:ff, :rebase, :method) do
+      true  | true  | :ff
+      true  | false | :ff
+      false | true  | :rebase_merge
+      false | false | :merge
     end
 
-    it 'returns "merge" merge_method when ff is disabled' do
-      project = build(:project, merge_requests_ff_only_enabled: false)
-      expect(project.merge_method).to be :merge
+    with_them do
+      let(:project) { build(:project, merge_requests_rebase_enabled: rebase, merge_requests_ff_only_enabled: ff) }
+
+      subject { project.merge_method }
+
+      it { is_expected.to eq(method) }
     end
   end
 

spec/presenters/merge_request_presenter_spec.rb

@@ -536,4 +536,67 @@ describe MergeRequestPresenter do
         .to eq("<a href=\"/#{resource.source_project.full_path}/tree/#{resource.source_branch}\">#{resource.source_branch}</a>")
     end
   end
+
+  describe '#rebase_path' do
+    before do
+      allow(resource).to receive(:rebase_in_progress?) { rebase_in_progress }
+      allow(resource).to receive(:should_be_rebased?) { should_be_rebased }
+
+      allow_any_instance_of(Gitlab::UserAccess::RequestCacheExtension)
+        .to receive(:can_push_to_branch?)
+        .with(resource.source_branch)
+        .and_return(can_push_to_branch)
+    end
+
+    subject do
+      described_class.new(resource, current_user: user).rebase_path
+    end
+
+    context 'when can rebase' do
+      let(:rebase_in_progress) { false }
+      let(:can_push_to_branch) { true }
+      let(:should_be_rebased) { true }
+
+      before do
+        allow(resource).to receive(:source_branch_exists?) { true }
+      end
+
+      it 'returns path' do
+        is_expected
+          .to eq("/#{project.full_path}/merge_requests/#{resource.iid}/rebase")
+      end
+    end
+
+    context 'when cannot rebase' do
+      context 'when rebase in progress' do
+        let(:rebase_in_progress) { true }
+        let(:can_push_to_branch) { true }
+        let(:should_be_rebased) { true }
+
+        it 'returns nil' do
+          is_expected.to be_nil
+        end
+      end
+
+      context 'when user cannot merge' do
+        let(:rebase_in_progress) { false }
+        let(:can_push_to_branch) { false }
+        let(:should_be_rebased) { true }
+
+        it 'returns nil' do
+          is_expected.to be_nil
+        end
+      end
+
+      context 'should not be rebased' do
+        let(:rebase_in_progress) { false }
+        let(:can_push_to_branch) { true }
+        let(:should_be_rebased) { false }
+
+        it 'returns nil' do
+          is_expected.to be_nil
+        end
+      end
+    end
+  end
 end