Merge branch '8333-add-related-epics-support' into 'master'

Add support for attaching epics to an epic

Closes #8333

See merge request gitlab-org/gitlab-ee!8637

db/schema.rb

@@ -1040,6 +1040,7 @@ ActiveRecord::Schema.define(version: 20181218192239) do
     t.integer "state", limit: 2, default: 1, null: false
     t.integer "closed_by_id"
     t.datetime "closed_at"
+    t.integer "parent_id"
     t.index ["assignee_id"], name: "index_epics_on_assignee_id", using: :btree
     t.index ["author_id"], name: "index_epics_on_author_id", using: :btree
     t.index ["closed_by_id"], name: "index_epics_on_closed_by_id", using: :btree
@@ -1047,6 +1048,7 @@ ActiveRecord::Schema.define(version: 20181218192239) do
     t.index ["group_id"], name: "index_epics_on_group_id", using: :btree
     t.index ["iid"], name: "index_epics_on_iid", using: :btree
     t.index ["milestone_id"], name: "index_milestone", using: :btree
+    t.index ["parent_id"], name: "index_epics_on_parent_id", using: :btree
     t.index ["start_date"], name: "index_epics_on_start_date", using: :btree
   end
 
@@ -3227,6 +3229,7 @@ ActiveRecord::Schema.define(version: 20181218192239) do
   add_foreign_key "epic_issues", "epics", on_delete: :cascade
   add_foreign_key "epic_issues", "issues", on_delete: :cascade
   add_foreign_key "epic_metrics", "epics", on_delete: :cascade
+  add_foreign_key "epics", "epics", column: "parent_id", name: "fk_25b99c1be3", on_delete: :cascade
   add_foreign_key "epics", "milestones", on_delete: :nullify
   add_foreign_key "epics", "namespaces", column: "group_id", name: "fk_f081aa4489", on_delete: :cascade
   add_foreign_key "epics", "users", column: "assignee_id", name: "fk_dccd3f98fc", on_delete: :nullify

ee/app/assets/javascripts/epics/epic_show/components/epic_show_app.vue

@@ -13,6 +13,7 @@ import { status, stateEvent } from '../../constants';
 
 export default {
   name: 'EpicShowApp',
+  epicsPathIdSeparator: '&',
   components: {
     epicHeader,
     epicSidebar,
@@ -44,6 +45,11 @@ export default {
       required: true,
       type: Boolean,
     },
+    subepicsSupported: {
+      type: Boolean,
+      required: false,
+      default: true,
+    },
     markdownPreviewPath: {
       type: String,
       required: true,
@@ -82,6 +88,10 @@ export default {
       type: Object,
       required: true,
     },
+    epicLinksEndpoint: {
+      type: String,
+      required: true,
+    },
     issueLinksEndpoint: {
       type: String,
       required: true,
@@ -146,6 +156,11 @@ export default {
       type: Array,
       required: true,
     },
+    parent: {
+      type: Object,
+      required: false,
+      default: () => ({}),
+    },
     participants: {
       type: Array,
       required: true,
@@ -198,7 +213,9 @@ export default {
     return {
       // Epics specific configuration
       issuableRef: '',
+      hasRelatedEpicsFeature: this.subepicsSupported && gon.features && gon.features.epicLinks,
       projectPath: this.groupPath,
+      parentEpic: this.parent ? this.parent : {},
       projectNamespace: '',
       service: new EpicsService({
         endpoint: this.endpoint,
@@ -293,6 +310,7 @@ export default {
         :initial-participants="participants"
         :initial-subscribed="subscribed"
         :initial-todo-exists="todoExists"
+        :parent="parentEpic"
         :namespace="namespace"
         :update-path="updateEndpoint"
         :labels-path="labelsPath"
@@ -302,12 +320,24 @@ export default {
         :labels-web-url="labelsWebUrl"
         :epics-web-url="epicsWebUrl"
       />
+      <related-issues-root
+        v-if="hasRelatedEpicsFeature"
+        :endpoint="epicLinksEndpoint"
+        :can-admin="canAdmin"
+        :can-reorder="canAdmin"
+        :allow-auto-complete="false"
+        :path-id-separator="$options.epicsPathIdSeparator"
+        :title="__('Epics')"
+        css-class="js-related-epics-block"
+      />
       <related-issues-root
         :endpoint="issueLinksEndpoint"
         :can-admin="canAdmin"
         :can-reorder="canAdmin"
         :allow-auto-complete="false"
-        title="Issues"
+        :title="__('Issues')"
+        css-class="js-related-issues-block"
+        path-id-separator="#"
       />
     </div>
   </div>

ee/app/assets/javascripts/epics/sidebar/components/sidebar_app.vue

@@ -12,6 +12,7 @@ import SidebarTodo from '~/sidebar/components/todo_toggle/todo.vue';
 import SidebarCollapsedGroupedDatePicker from '~/vue_shared/components/sidebar/collapsed_grouped_date_picker.vue';
 import ToggleSidebar from '~/vue_shared/components/sidebar/toggle_sidebar.vue';
 import SidebarLabelsSelect from '~/vue_shared/components/sidebar/labels_select/base.vue';
+import SidebarItemEpic from 'ee/sidebar/components/sidebar_item_epic.vue';
 import { parseBoolean } from '~/lib/utils/common_utils';
 import eventHub from '../../event_hub';
 import SidebarDatePicker from './sidebar_date_picker.vue';
@@ -33,6 +34,7 @@ export default {
     SidebarDatePicker,
     SidebarCollapsedGroupedDatePicker,
     SidebarLabelsSelect,
+    SidebarItemEpic,
     SidebarParticipants,
     SidebarSubscriptions,
   },
@@ -116,6 +118,10 @@ export default {
       type: Boolean,
       required: true,
     },
+    parent: {
+      type: Object,
+      required: true,
+    },
     namespace: {
       type: String,
       required: false,
@@ -549,6 +555,9 @@ export default {
         @toggleCollapse="toggleSidebarRevealLabelsDropdown"
         >{{ __('None') }}</sidebar-labels-select
       >
+      <div class="block parent-epic">
+        <sidebar-item-epic :block-title="__('Parent epic')" :initial-epic="parent" />
+      </div>
       <sidebar-participants :participants="initialParticipants" @toggleCollapse="toggleSidebar" />
       <sidebar-subscriptions
         :loading="savingSubscription"

ee/app/assets/javascripts/related_issues/components/add_issuable_form.vue

@@ -2,7 +2,6 @@
 import $ from 'jquery';
 import GfmAutoComplete from '~/gfm_auto_complete';
 import { GlLoadingIcon } from '@gitlab/ui';
-import eventHub from '../event_hub';
 import issueToken from './issue_token.vue';
 
 export default {
@@ -60,7 +59,6 @@ export default {
 
   mounted() {
     const $input = $(this.$refs.input);
-
     if (this.allowAutoComplete) {
       this.gfmAutoComplete = new GfmAutoComplete(this.autoCompleteSources);
       this.gfmAutoComplete.setup($input, {
@@ -83,7 +81,10 @@ export default {
   methods: {
     onInput() {
       const { value } = this.$refs.input;
-      eventHub.$emit('addIssuableFormInput', value, $(this.$refs.input).caret('pos'));
+      this.$emit('addIssuableFormInput', {
+        newValue: value,
+        caretPos: $(this.$refs.input).caret('pos'),
+      });
     },
     onFocus() {
       this.isInputFocused = true;
@@ -94,7 +95,7 @@ export default {
       // Avoid tokenizing partial input when clicking an autocomplete item
       if (!this.isAutoCompleteOpen) {
         const { value } = this.$refs.input;
-        eventHub.$emit('addIssuableFormBlur', value);
+        this.$emit('addIssuableFormBlur', value);
       }
     },
     onAutoCompleteToggled(isOpen) {
@@ -103,12 +104,15 @@ export default {
     onInputWrapperClick() {
       this.$refs.input.focus();
     },
+    onPendingIssuableRemoveRequest(params) {
+      this.$emit('pendingIssuableRemoveRequest', params);
+    },
     onFormSubmit() {
       const { value } = this.$refs.input;
-      eventHub.$emit('addIssuableFormSubmit', value);
+      this.$emit('addIssuableFormSubmit', value);
     },
     onFormCancel() {
-      eventHub.$emit('addIssuableFormCancel');
+      this.$emit('addIssuableFormCancel');
     },
   },
 };
@@ -141,6 +145,7 @@ export default {
             :is-condensed="true"
             :path-id-separator="pathIdSeparator"
             event-namespace="pendingIssuable"
+            @pendingIssuableRemoveRequest="onPendingIssuableRemoveRequest"
           />
         </li>
         <li class="add-issuable-form-input-list-item">

ee/app/assets/javascripts/related_issues/components/issue_item.vue

@@ -89,7 +89,7 @@ export default {
         </div>
         <div class="item-meta-child d-flex align-items-center">
           <issue-milestone
-            v-if="milestone"
+            v-if="hasMilestone"
             :milestone="milestone"
             class="d-flex align-items-center item-milestone"
           />

ee/app/assets/javascripts/related_issues/components/related_issues_block.vue

@@ -4,7 +4,6 @@ import tooltip from '~/vue_shared/directives/tooltip';
 import Icon from '~/vue_shared/components/icon.vue';
 import sortableConfig from 'ee/sortable/sortable_config';
 import { GlLoadingIcon } from '@gitlab/ui';
-import eventHub from '../event_hub';
 import issueItem from './issue_item.vue';
 import addIssuableForm from './add_issuable_form.vue';
 
@@ -62,8 +61,7 @@ export default {
     },
     pathIdSeparator: {
       type: String,
-      required: false,
-      default: '#',
+      required: true,
     },
     helpPath: {
       type: String,
@@ -110,9 +108,6 @@ export default {
     }
   },
   methods: {
-    toggleAddRelatedIssuesForm() {
-      eventHub.$emit('toggleAddRelatedIssuesForm');
-    },
     getBeforeAfterId(itemEl) {
       const prevItemEl = itemEl.previousElementSibling;
       const nextItemEl = itemEl.nextElementSibling;
@@ -172,7 +167,7 @@ export default {
               class="js-issue-count-badge-add-button issue-count-badge-add-button btn btn-sm btn-default qa-add-issues-button"
               aria-label="Add an issue"
               data-placement="top"
-              @click="toggleAddRelatedIssuesForm"
+              @click="$emit('toggleAddRelatedIssuesForm', $event);"
             >
               <i class="fa fa-plus" aria-hidden="true"></i>
             </button>
@@ -192,6 +187,11 @@ export default {
           :pending-references="pendingReferences"
           :auto-complete-sources="autoCompleteSources"
           :path-id-separator="pathIdSeparator"
+          @pendingIssuableRemoveRequest="$emit('pendingIssuableRemoveRequest', $event);"
+          @addIssuableFormInput="$emit('addIssuableFormInput', $event);"
+          @addIssuableFormBlur="$emit('addIssuableFormBlur', $event);"
+          @addIssuableFormSubmit="$emit('addIssuableFormSubmit', $event);"
+          @addIssuableFormCancel="$emit('addIssuableFormCancel', $event);"
         />
       </div>
       <div
@@ -238,6 +238,7 @@ export default {
               :can-reorder="canReorder"
               :path-id-separator="pathIdSeparator"
               event-namespace="relatedIssue"
+              @relatedIssueRemoveRequest="$emit('relatedIssueRemoveRequest', $event);"
             />
           </li>
         </ul>

ee/app/assets/javascripts/related_issues/components/related_issues_root.vue

@@ -25,7 +25,6 @@ Your caret can stop touching a `rawReference` can happen in a variety of ways:
 */
 import _ from 'underscore';
 import Flash from '~/flash';
-import eventHub from '../event_hub';
 import RelatedIssuesBlock from './related_issues_block.vue';
 import RelatedIssuesStore from '../stores/related_issues_store';
 import RelatedIssuesService from '../services/related_issues_service';
@@ -67,6 +66,16 @@ export default {
       required: false,
       default: true,
     },
+    pathIdSeparator: {
+      type: String,
+      required: false,
+      default: '#',
+    },
+    cssClass: {
+      type: String,
+      required: false,
+      default: '',
+    },
   },
   data() {
     this.store = new RelatedIssuesStore();
@@ -86,26 +95,9 @@ export default {
     },
   },
   created() {
-    eventHub.$on('relatedIssue-removeRequest', this.onRelatedIssueRemoveRequest);
-    eventHub.$on('toggleAddRelatedIssuesForm', this.onToggleAddRelatedIssuesForm);
-    eventHub.$on('pendingIssuable-removeRequest', this.onPendingIssueRemoveRequest);
-    eventHub.$on('addIssuableFormSubmit', this.onPendingFormSubmit);
-    eventHub.$on('addIssuableFormCancel', this.onPendingFormCancel);
-    eventHub.$on('addIssuableFormInput', this.onInput);
-    eventHub.$on('addIssuableFormBlur', this.onBlur);
-
     this.service = new RelatedIssuesService(this.endpoint);
     this.fetchRelatedIssues();
   },
-  beforeDestroy() {
-    eventHub.$off('relatedIssue-removeRequest', this.onRelatedIssueRemoveRequest);
-    eventHub.$off('toggleAddRelatedIssuesForm', this.onToggleAddRelatedIssuesForm);
-    eventHub.$off('pendingIssuable-removeRequest', this.onPendingIssueRemoveRequest);
-    eventHub.$off('addIssuableFormSubmit', this.onPendingFormSubmit);
-    eventHub.$off('addIssuableFormCancel', this.onPendingFormCancel);
-    eventHub.$off('addIssuableFormInput', this.onInput);
-    eventHub.$off('addIssuableFormBlur', this.onBlur);
-  },
   methods: {
     onRelatedIssueRemoveRequest(idToRemove) {
       const issueToRemove = _.find(this.state.relatedIssues, issue => issue.id === idToRemove);
@@ -198,7 +190,7 @@ export default {
           });
       }
     },
-    onInput(newValue, caretPos) {
+    onInput({ newValue, caretPos }) {
       const rawReferences = newValue.split(/\s/);
 
       let touchedReference;
@@ -235,6 +227,7 @@ export default {
 
 <template>
   <related-issues-block
+    :class="cssClass"
     :help-path="helpPath"
     :is-fetching="isFetching"
     :is-submitting="isSubmitting"
@@ -246,7 +239,14 @@ export default {
     :input-value="inputValue"
     :auto-complete-sources="autoCompleteSources"
     :title="title"
-    path-id-separator="#"
+    :path-id-separator="pathIdSeparator"
     @saveReorder="saveIssueOrder"
+    @toggleAddRelatedIssuesForm="onToggleAddRelatedIssuesForm"
+    @addIssuableFormInput="onInput"
+    @addIssuableFormBlur="onBlur"
+    @addIssuableFormSubmit="onPendingFormSubmit"
+    @addIssuableFormCancel="onPendingFormCancel"
+    @pendingIssuableRemoveRequest="onPendingIssueRemoveRequest"
+    @relatedIssueRemoveRequest="onRelatedIssueRemoveRequest"
   />
 </template>

ee/app/assets/javascripts/related_issues/event_hub.js

-import Vue from 'vue';
-
-export default new Vue();

ee/app/assets/javascripts/related_issues/mixins/related_issues_mixin.js

+import _ from 'underscore';
 import { formatDate } from '~/lib/utils/datetime_utility';
 import tooltip from '~/vue_shared/directives/tooltip';
 import icon from '~/vue_shared/components/icon.vue';
 import timeagoMixin from '~/vue_shared/mixins/timeago';
-import eventHub from '../event_hub';
 
 const mixins = {
   data() {
@@ -104,6 +104,9 @@ const mixins = {
     hasTitle() {
       return this.title.length > 0;
     },
+    hasMilestone() {
+      return !_.isEmpty(this.milestone);
+    },
     iconName() {
       return this.isOpen ? 'issue-open-m' : 'issue-close';
     },
@@ -139,10 +142,10 @@ const mixins = {
     onRemoveRequest() {
       let namespacePrefix = '';
       if (this.eventNamespace && this.eventNamespace.length > 0) {
-        namespacePrefix = `${this.eventNamespace}-`;
+        namespacePrefix = `${this.eventNamespace}`;
       }
 
-      eventHub.$emit(`${namespacePrefix}removeRequest`, this.idKey);
+      this.$emit(`${namespacePrefix}RemoveRequest`, this.idKey);
 
       this.removeDisabled = true;
     },

ee/app/assets/javascripts/sidebar/components/sidebar_item_epic.vue

@@ -13,29 +13,44 @@ export default {
   components: {
     GlLoadingIcon,
   },
+  props: {
+    blockTitle: {
+      type: String,
+      required: false,
+      default: __('Epic'),
+    },
+    initialEpic: {
+      type: Object,
+      required: false,
+      default: () => null,
+    },
+  },
   data() {
     return {
-      store: new Store(),
+      store: !this.initialEpic ? new Store() : {},
     };
   },
   computed: {
     isLoading() {
-      return this.store.isFetching.epic;
+      return this.initialEpic ? false : this.store.isFetching.epic;
+    },
+    epic() {
+      return this.initialEpic || this.store.epic;
     },
     epicIcon() {
       return spriteIcon('epic');
     },
     epicUrl() {
-      return this.store.epic.url;
+      return this.epic.url;
     },
     epicTitle() {
-      return this.store.epic.title;
+      return this.epic.title;
     },
     hasEpic() {
       return this.epicUrl && this.epicTitle;
     },
     collapsedTitle() {
-      return this.hasEpic ? this.epicTitle : 'None';
+      return this.hasEpic ? this.epicTitle : __('None');
     },
     tooltipTitle() {
       if (!this.hasEpic) {
@@ -43,13 +58,13 @@ export default {
       }
       let tooltipTitle = this.epicTitle;
 
-      if (this.store.epic.human_readable_end_date || this.store.epic.human_readable_timestamp) {
+      if (this.epic.human_readable_end_date || this.epic.human_readable_timestamp) {
         tooltipTitle += '<br />';
-        tooltipTitle += this.store.epic.human_readable_end_date
-          ? `${this.store.epic.human_readable_end_date} `
+        tooltipTitle += this.epic.human_readable_end_date
+          ? `${this.epic.human_readable_end_date} `
           : '';
-        tooltipTitle += this.store.epic.human_readable_timestamp
-          ? `(${this.store.epic.human_readable_timestamp})`
+        tooltipTitle += this.epic.human_readable_timestamp
+          ? `(${this.epic.human_readable_timestamp})`
           : '';
       }
 
@@ -71,15 +86,15 @@ export default {
       data-boundary="viewport"
     >
       <div v-html="epicIcon"></div>
-      <span v-if="!isLoading" class="collapse-truncated-title"> {{ collapsedTitle }} </span>
+      <span v-if="!isLoading" class="collapse-truncated-title">{{ collapsedTitle }}</span>
     </div>
     <div class="title hide-collapsed">
-      Epic
+      {{ blockTitle }}
       <gl-loading-icon v-if="isLoading" :inline="true" />
     </div>
     <div v-if="!isLoading" class="value hide-collapsed">
-      <a v-if="hasEpic" :href="epicUrl" class="bold"> {{ epicTitle }} </a>
-      <span v-else class="no-value"> None </span>
+      <a v-if="hasEpic" :href="epicUrl" class="bold">{{ epicTitle }}</a>
+      <span v-else class="no-value">{{ __('None') }}</span>
     </div>
   </div>
 </template>

ee/app/controllers/groups/epic_links_controller.rb

+# frozen_string_literal: true
+
+class Groups::EpicLinksController < Groups::EpicsController
+  include EpicRelations
+
+  before_action :check_feature_flag!
+  before_action :check_nested_support!
+
+  before_action do
+    push_frontend_feature_flag(:epic_links)
+  end
+
+  def destroy
+    result = ::Epics::UpdateService.new(group, current_user, { parent: nil }).execute(child_epic)
+
+    render json: { issuables: issuables }, status: result[:http_status]
+  end
+
+  private
+
+  def create_service
+    EpicLinks::CreateService.new(epic, current_user, create_params)
+  end
+
+  def list_service
+    EpicLinks::ListService.new(epic, current_user)
+  end
+
+  def child_epic
+    @child_epic ||= Epic.find(params[:id])
+  end
+
+  def check_feature_flag!
+    render_404 unless Feature.enabled?(:epic_links, group)
+  end
+
+  def check_nested_support!
+    render_404 unless Epic.supports_nested_objects?
+  end
+end

ee/app/controllers/groups/epics_controller.rb

@@ -8,6 +8,10 @@ class Groups::EpicsController < Groups::ApplicationController
   include RendersNotes
   include EpicsActions
 
+  before_action do
+    push_frontend_feature_flag(:epic_links)
+  end
+
   before_action :check_epics_available!
   before_action :epic, except: [:index, :create]
   before_action :set_issuables_index, only: :index

ee/app/finders/epics_finder.rb

@@ -30,6 +30,7 @@ class EpicsFinder < IssuableFinder
     items = by_timeframe(items)
     items = by_state(items)
     items = by_label(items)
+    items = by_parent(items)
 
     sort(items)
   end
@@ -89,4 +90,16 @@ class EpicsFinder < IssuableFinder
     items
   end
   # rubocop: enable CodeReuse/ActiveRecord
+
+  def parent_id?
+    params[:parent_id].present?
+  end
+
+  # rubocop: disable CodeReuse/ActiveRecord
+  def by_parent(items)
+    return items unless parent_id?
+
+    items.where(parent_id: params[:parent_id])
+  end
+  # rubocop: enable CodeReuse/ActiveRecord
 end

ee/app/finders/geo/attachment_registry_finder.rb

@@ -108,10 +108,10 @@ module Geo
     def group_uploads
       namespace_ids =
         if current_node.selective_sync_by_namespaces?
-          Gitlab::GroupHierarchy.new(current_node.namespaces).base_and_descendants.select(:id)
+          Gitlab::ObjectHierarchy.new(current_node.namespaces).base_and_descendants.select(:id)
         elsif current_node.selective_sync_by_shards?
           leaf_groups = Namespace.where(id: current_node.projects.select(:namespace_id))
-          Gitlab::GroupHierarchy.new(leaf_groups).base_and_ancestors.select(:id)
+          Gitlab::ObjectHierarchy.new(leaf_groups).base_and_ancestors.select(:id)
         else
           Namespace.none
         end

ee/app/helpers/ee/issuables_helper.rb

@@ -20,6 +20,8 @@ module EE
 
       if parent.is_a?(Group)
         data[:issueLinksEndpoint] = group_epic_issues_path(parent, issuable)
+        data[:epicLinksEndpoint] = group_epic_links_path(parent, issuable)
+        data[:subepicsSupported] = ::Epic.supports_nested_objects?
       end
 
       data

ee/app/helpers/epics_helper.rb

@@ -9,6 +9,7 @@ module EpicsHelper
       epic_id: epic.id,
       created: epic.created_at,
       author: epic_author(epic, opts),
+      parent: epic_parent(epic.parent),
       todo_exists: todo.present?,
       todo_path: group_todos_path(group),
       start_date: epic.start_date,
@@ -67,6 +68,16 @@ module EpicsHelper
     }
   end
 
+  def epic_parent(epic)
+    return unless epic
+
+    {
+      id: epic.id,
+      title: epic.title,
+      url: epic_path(epic)
+    }
+  end
+
   def epic_endpoint_query_params(opts)
     opts[:data] ||= {}
     opts[:data][:endpoint_query_params] = {

ee/app/models/ee/epic.rb

@@ -12,6 +12,7 @@ module EE
       include Referable
       include Awardable
       include LabelEventable
+      include Descendant
 
       enum state: { opened: 1, closed: 2 }
 
@@ -33,6 +34,8 @@ module EE
       belongs_to :group
       belongs_to :start_date_sourcing_milestone, class_name: 'Milestone'
       belongs_to :due_date_sourcing_milestone, class_name: 'Milestone'
+      belongs_to :parent, class_name: "Epic"
+      has_many :children, class_name: "Epic", foreign_key: :parent_id
 
       has_internal_id :iid, scope: :group, init: ->(s) { s&.group&.epics&.maximum(:iid) }
 
@@ -215,6 +218,20 @@ module EE
       from && from != group
     end
 
+    def ancestors
+      return self.class.none unless parent_id
+
+      hierarchy.ancestors
+    end
+
+    def descendants
+      hierarchy.descendants
+    end
+
+    def hierarchy
+      ::Gitlab::ObjectHierarchy.new(self.class.where(id: id))
+    end
+
     # we don't support project epics for epics yet, planned in the future #4019
     def update_project_counter_caches
     end

ee/app/models/ee/user.rb

@@ -186,7 +186,7 @@ module EE
         project_creation_levels << nil
       end
 
-      developer_groups_hierarchy = ::Gitlab::GroupHierarchy.new(developer_groups).base_and_descendants
+      developer_groups_hierarchy = ::Gitlab::ObjectHierarchy.new(developer_groups).base_and_descendants
       ::Group.where(id: developer_groups_hierarchy.select(:id),
                     project_creation_level: project_creation_levels)
     end

ee/app/models/geo_node.rb

@@ -187,7 +187,7 @@ class GeoNode < ActiveRecord::Base
     return Project.all unless selective_sync?
 
     if selective_sync_by_namespaces?
-      query = Gitlab::GroupHierarchy.new(namespaces).base_and_descendants
+      query = Gitlab::ObjectHierarchy.new(namespaces).base_and_descendants
       Project.where(namespace_id: query.select(:id))
     elsif selective_sync_by_shards?
       Project.where(repository_storage: selective_sync_shards)

ee/app/services/ee/ci/register_job_service.rb

@@ -52,7 +52,7 @@ module EE
         namespaces = ::Namespace.reorder(nil).where('namespaces.id = projects.namespace_id')
 
         if ::Feature.enabled?(:shared_runner_minutes_on_root_namespace)
-          namespaces = ::Gitlab::GroupHierarchy.new(namespaces).roots
+          namespaces = ::Gitlab::ObjectHierarchy.new(namespaces).roots
         end
 
         namespaces

ee/app/services/epic_links/create_service.rb

+# frozen_string_literal: true
+
+module EpicLinks
+  class CreateService < IssuableLinks::CreateService
+    def execute
+      return error('Epic hierarchy level too deep', 409) if parent_ancestors_count >= 4
+
+      super
+    end
+
+    private
+
+    def relate_issuables(referenced_epic)
+      affected_epics = [issuable]
+      affected_epics << referenced_epic if referenced_epic.parent
+
+      referenced_epic.update(parent: issuable)
+      affected_epics.each(&:update_start_and_due_dates)
+    end
+
+    def linkable_issuables(epics)
+      @linkable_issuables ||= begin
+        return [] unless can?(current_user, :admin_epic, issuable.group)
+
+        epics.select do |epic|
+          issuable_group_descendants.include?(epic.group) &&
+            !previous_related_issuables.include?(epic) &&
+            !level_depth_exceeded?(epic)
+        end
+      end
+    end
+
+    def references(extractor)
+      extractor.epics
+    end
+
+    def extractor_context
+      { group: issuable.group }
+    end
+
+    def previous_related_issuables
+      issuable.children.to_a
+    end
+
+    def issuable_group_descendants
+      @descendants ||= issuable.group.self_and_descendants
+    end
+
+    def level_depth_exceeded?(epic)
+      depth_level(epic) + parent_ancestors_count >= 5
+    end
+
+    def depth_level(epic)
+      epic.descendants.count + 1 # level including epic -> therefore +1
+    end
+
+    def parent_ancestors_count
+      @parent_ancestors_count ||= issuable.ancestors.count
+    end
+
+    def issuables_assigned_message
+      'Epic(s) already assigned'
+    end
+
+    def issuables_not_found_message
+      'No Epic found for given params'
+    end
+  end
+end

ee/app/services/epic_links/list_service.rb

+# frozen_string_literal: true
+
+module EpicLinks
+  class ListService < IssuableLinks::ListService
+    private
+
+    def child_issuables
+      return [] unless issuable&.group&.feature_available?(:epics)
+
+      EpicsFinder.new(current_user, parent_id: issuable.id, group_id: issuable.group.id).execute
+    end
+
+    def reference(epic)
+      epic.to_reference(issuable.group)
+    end
+
+    def issuable_path(epic)
+      group_epic_path(epic.group, epic)
+    end
+
+    def relation_path(epic)
+      group_epic_link_path(epic.group, issuable.iid, epic.id)
+    end
+
+    def to_hash(object)
+      {
+        id: object.id,
+        title: object.title,
+        state: object.state,
+        reference: reference(object),
+        path: issuable_path(object),
+        relation_path: relation_path(object)
+      }
+    end
+  end
+end

ee/config/routes/group.rb

@@ -57,6 +57,7 @@ constraints(::Constraints::GroupUrlConstrainer.new) do
       end
 
       resources :epic_issues, only: [:index, :create, :destroy, :update], as: 'issues', path: 'issues'
+      resources :epic_links, only: [:index, :create, :destroy, :update], as: 'links', path: 'links'
 
       scope module: :epics do
         resources :notes, only: [:index, :create, :destroy, :update], concerns: :awardable, constraints: { id: /\d+/ }

ee/db/migrate/20181123090058_add_parent_to_epic.rb

+# frozen_string_literal: true
+
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+class AddParentToEpic < ActiveRecord::Migration[5.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def up
+    add_column :epics, :parent_id, :integer
+  end
+
+  def down
+    remove_column :epics, :parent_id
+  end
+end

ee/db/migrate/20181123100058_add_parent_epic_fk.rb

+# frozen_string_literal: true
+
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+class AddParentEpicFk < ActiveRecord::Migration[5.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_foreign_key :epics, :epics, column: :parent_id, on_delete: :cascade
+    add_concurrent_index :epics, :parent_id
+  end
+
+  def down
+    remove_foreign_key :epics, column: :parent_id
+    remove_concurrent_index :epics, :parent_id
+  end
+end

ee/lib/gitlab/group_plans_preloader.rb

@@ -58,7 +58,7 @@ module Gitlab
     # Returns an ActiveRecord::Relation that includes the given groups, and all
     # their (recursive) ancestors.
     def groups_and_ancestors_for(groups)
-      Gitlab::GroupHierarchy
+      Gitlab::ObjectHierarchy
         .new(groups)
         .base_and_ancestors
         .select(:id, :parent_id, :plan_id)

ee/spec/controllers/groups/epic_links_controller_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Groups::EpicLinksController, :postgresql do
+  let(:group) { create(:group, :public) }
+  let(:parent_epic) { create(:epic, group: group) }
+  let(:epic1) { create(:epic, group: group) }
+  let(:epic2) { create(:epic, group: group) }
+  let(:user)  { create(:user) }
+
+  before do
+    sign_in(user)
+  end
+
+  shared_examples 'unlicensed epics action' do
+    before do
+      stub_licensed_features(epics: false)
+      group.add_developer(user)
+
+      subject
+    end
+
+    it 'returns 400 status' do
+      expect(response).to have_gitlab_http_status(404)
+    end
+  end
+
+  shared_examples 'feature flag disabled' do
+    before do
+      stub_licensed_features(epics: true)
+      stub_feature_flags(epic_links: false)
+      group.add_developer(user)
+
+      subject
+    end
+
+    it 'returns 400 status' do
+      expect(response).to have_gitlab_http_status(404)
+    end
+  end
+
+  describe 'GET #index' do
+    before do
+      epic1.update(parent: parent_epic)
+    end
+
+    subject { get :index, group_id: group, epic_id: parent_epic.to_param }
+
+    it_behaves_like 'unlicensed epics action'
+    it_behaves_like 'feature flag disabled'
+
+    context 'when epic_links feature is enabled' do
+      before do
+        stub_licensed_features(epics: true)
+        stub_feature_flags(epic_linkcs: true)
+        group.add_developer(user)
+
+        subject
+      end
+
+      it 'returns the correct JSON response' do
+        list_service_response = EpicLinks::ListService.new(parent_epic, user).execute
+
+        expect(response).to have_gitlab_http_status(200)
+        expect(json_response).to eq(list_service_response.as_json)
+      end
+    end
+  end
+
+  describe 'POST #create' do
+    subject do
+      reference = [epic1.to_reference(full: true)]
+
+      post :create, group_id: group, epic_id: parent_epic.to_param, issuable_references: reference
+    end
+
+    it_behaves_like 'unlicensed epics action'
+    it_behaves_like 'feature flag disabled'
+
+    context 'when epic_links feature is enabled' do
+      before do
+        stub_licensed_features(epics: true)
+        stub_feature_flags(epic_linkcs: true)
+      end
+
+      context 'when user has permissions to create requested association' do
+        before do
+          group.add_developer(user)
+        end
+
+        it 'returns correct response for the correct issue reference' do
+          subject
+          list_service_response = EpicLinks::ListService.new(parent_epic, user).execute
+
+          expect(response).to have_gitlab_http_status(200)
+          expect(json_response).to eq('message' => nil, 'issuables' => list_service_response.as_json)
+        end
+
+        it 'updates a parent for the referenced epic' do
+          expect { subject }.to change { epic1.reload.parent }.from(nil).to(parent_epic)
+        end
+      end
+
+      context 'when user does not have permissions to create requested association' do
+        it 'returns 403 status' do
+          subject
+
+          expect(response).to have_gitlab_http_status(403)
+        end
+
+        it 'does not update parent attribute' do
+          expect { subject }.not_to change { epic1.reload.parent }.from(nil)
+        end
+      end
+    end
+  end
+
+  describe 'DELETE #destroy' do
+    before do
+      epic1.update(parent: parent_epic)
+    end
+
+    subject { delete :destroy, group_id: group, epic_id: parent_epic.to_param, id: epic1.id }
+
+    it_behaves_like 'unlicensed epics action'
+    it_behaves_like 'feature flag disabled'
+
+    context 'when epic_links feature is enabled' do
+      before do
+        stub_licensed_features(epics: true)
+        stub_feature_flags(epic_linkcs: true)
+      end
+
+      context 'when user has permissions to update the parent epic' do
+        before do
+          group.add_developer(user)
+        end
+
+        it 'returns status 200' do
+          subject
+
+          expect(response.status).to eq(200)
+        end
+
+        it 'destroys the link' do
+          expect { subject }.to change { epic1.reload.parent }.from(parent_epic).to(nil)
+        end
+      end
+
+      context 'when user does not have permissions to update the parent epic' do
+        it 'returns status 404' do
+          subject
+
+          expect(response.status).to eq(403)
+        end
+
+        it 'does not destroy the link' do
+          expect { subject }.not_to change { epic1.reload.parent }.from(parent_epic)
+        end
+      end
+
+      context 'when the epic does not have any parent' do
+        it 'returns status 404' do
+          delete :destroy, group_id: group, epic_id: parent_epic.to_param, id: epic2.id
+
+          expect(response.status).to eq(403)
+        end
+      end
+    end
+  end
+end

ee/spec/features/epics/epic_issues_spec.rb

@@ -32,7 +32,7 @@ describe 'Epic Issues', :js do
     end
 
     it 'user can see issues from public project but cannot delete the associations' do
-      within('.related-issues-block ul.related-items-list') do
+      within('.js-related-issues-block ul.related-items-list') do
         expect(page).to have_selector('li', count: 1)
         expect(page).to have_content(public_issue.title)
         expect(page).not_to have_selector('button.js-issue-item-remove-button')
@@ -40,11 +40,11 @@ describe 'Epic Issues', :js do
     end
 
     it 'user cannot add new issues to the epic' do
-      expect(page).not_to have_selector('.related-issues-block h3.card-title button')
+      expect(page).not_to have_selector('.js-related-issues-block h3.card-title button')
     end
 
     it 'user cannot reorder issues in epic' do
-      expect(page).not_to have_selector('.js-related-issues-token-list-item.user-can-drag')
+      expect(page).not_to have_selector('.js-related-issues-block .js-related-issues-token-list-item.user-can-drag')
     end
   end
 
@@ -53,13 +53,13 @@ describe 'Epic Issues', :js do
     let(:issue_invalid) { create(:issue) }
 
     def add_issues(references)
-      find('.related-issues-block h3.card-title button').click
-      find('.js-add-issuable-form-input').set(references)
+      find('.js-related-issues-block h3.card-title button').click
+      find('.js-related-issues-block .js-add-issuable-form-input').set(references)
       # When adding long references, for some reason the input gets stuck
       # waiting for more text. Send a keystroke before clicking the button to
       # get out of this mode.
-      find('.js-add-issuable-form-input').send_keys(:tab)
-      find('.js-add-issuable-form-add-button').click
+      find('.js-related-issues-block .js-add-issuable-form-input').send_keys(:tab)
+      find('.js-related-issues-block .js-add-issuable-form-add-button').click
 
       wait_for_requests
     end
@@ -70,7 +70,7 @@ describe 'Epic Issues', :js do
     end
 
     it 'user can see all issues of the group and delete the associations' do
-      within('.related-issues-block ul.related-items-list') do
+      within('.js-related-issues-block ul.related-items-list') do
         expect(page).to have_selector('li', count: 2)
         expect(page).to have_content(public_issue.title)
         expect(page).to have_content(private_issue.title)
@@ -80,7 +80,7 @@ describe 'Epic Issues', :js do
 
       wait_for_requests
 
-      within('.related-issues-block ul.related-items-list') do
+      within('.js-related-issues-block ul.related-items-list') do
         expect(page).to have_selector('li', count: 1)
       end
     end
@@ -100,20 +100,20 @@ describe 'Epic Issues', :js do
       expect(page).not_to have_selector('.content-wrapper .alert-wrapper .flash-text')
       expect(page).not_to have_content('No Issue found for given params')
 
-      within('.related-issues-block ul.related-items-list') do
+      within('.js-related-issues-block ul.related-items-list') do
         expect(page).to have_selector('li', count: 3)
         expect(page).to have_content(issue_to_add.title)
       end
     end
 
     it 'user can reorder issues in epic' do
-      expect(first('.js-related-issues-token-list-item')).to have_content(public_issue.title)
-      expect(page.all('.js-related-issues-token-list-item').last).to have_content(private_issue.title)
+      expect(first('.js-related-issues-block .js-related-issues-token-list-item')).to have_content(public_issue.title)
+      expect(page.all('.js-related-issues-block .js-related-issues-token-list-item').last).to have_content(private_issue.title)
 
-      drag_to(selector: '.related-items-list', to_index: 1)
+      drag_to(selector: '.js-related-issues-block .related-items-list', to_index: 1)
 
-      expect(first('.js-related-issues-token-list-item')).to have_content(private_issue.title)
-      expect(page.all('.js-related-issues-token-list-item').last).to have_content(public_issue.title)
+      expect(first('.js-related-issues-block .js-related-issues-token-list-item')).to have_content(private_issue.title)
+      expect(page.all('.js-related-issues-block .js-related-issues-token-list-item').last).to have_content(public_issue.title)
     end
   end
 end

ee/spec/features/issues/epic_in_issue_sidebar_spec.rb

@@ -28,6 +28,10 @@ describe 'Epic in issue sidebar', :js do
   context 'when epics available' do
     before do
       stub_licensed_features(epics: true)
+
+      sign_in(user)
+      visit project_issue_path(project, issue)
+      wait_for_requests
     end
 
     it_behaves_like 'epic in issue sidebar'

ee/spec/finders/epics_finder_spec.rb

@@ -169,6 +169,21 @@ describe EpicsFinder do
             expect(epics(params)).to contain_exactly(epic3)
           end
         end
+
+        context 'by parent' do
+          before do
+            epic2.update(parent: epic1)
+            epic3.update(parent: epic2)
+          end
+
+          it 'returns direct children of the parent' do
+            params = {
+              parent_id: epic1.id
+            }
+
+            expect(epics(params)).to contain_exactly(epic2)
+          end
+        end
       end
     end
   end

ee/spec/helpers/ee/issuables_helper_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe IssuablesHelper do
+  describe '#issuable_initial_data' do
+    it 'returns the correct data for an epic' do
+      user = create(:user)
+      epic = create(:epic, author: user, description: 'epic text')
+      @group = epic.group
+
+      allow(helper).to receive(:current_user).and_return(user)
+      allow(helper).to receive(:can?).and_return(true)
+
+      expected_data = {
+        endpoint: "/groups/#{@group.full_path}/-/epics/#{epic.iid}",
+        epicLinksEndpoint: "/groups/#{@group.full_path}/-/epics/#{epic.iid}/links",
+        updateEndpoint: "/groups/#{@group.full_path}/-/epics/#{epic.iid}.json",
+        issueLinksEndpoint: "/groups/#{@group.full_path}/-/epics/#{epic.iid}/issues",
+        canUpdate: true,
+        canDestroy: true,
+        canAdmin: true,
+        issuableRef: "&#{epic.iid}",
+        markdownPreviewPath: "/groups/#{@group.full_path}/preview_markdown",
+        markdownDocsPath: '/help/user/markdown',
+        markdownVersion: CacheMarkdownField::CACHE_COMMONMARK_VERSION,
+        issuableTemplates: nil,
+        groupPath: @group.path,
+        initialTitleHtml: epic.title,
+        initialTitleText: epic.title,
+        initialDescriptionHtml: '<p dir="auto">epic text</p>',
+        initialDescriptionText: 'epic text',
+        initialTaskStatus: '0 of 0 tasks completed',
+        subepicsSupported: Gitlab::Database.postgresql?
+      }
+      expect(helper.issuable_initial_data(epic)).to eq(expected_data)
+    end
+  end
+end

ee/spec/helpers/epics_helper_spec.rb

@@ -5,16 +5,20 @@ describe EpicsHelper do
 
   describe '#epic_show_app_data' do
     let(:user) { create(:user) }
+    let(:group) { create(:group) }
     let(:milestone1) { create(:milestone, title: 'make me a sandwich', start_date: '2010-01-01', due_date: '2019-12-31') }
     let(:milestone2) { create(:milestone, title: 'make me a pizza', start_date: '2020-01-01', due_date: '2029-12-31') }
+    let(:parent_epic) { create(:epic, group: group) }
     let!(:epic) do
       create(
         :epic,
+        group: group,
         author: user,
         start_date_sourcing_milestone: milestone1,
         start_date: Date.new(2000, 1, 1),
         due_date_sourcing_milestone: milestone2,
-        due_date: Date.new(2000, 1, 2)
+        due_date: Date.new(2000, 1, 2),
+        parent: parent_epic
       )
     end
 
@@ -30,7 +34,7 @@ describe EpicsHelper do
       expected_keys = %i(initial meta namespace labels_path toggle_subscription_path labels_web_url epics_web_url)
       expect(data.keys).to match_array(expected_keys)
       expect(meta_data.keys).to match_array(%w[
-        epic_id created author todo_exists todo_path start_date
+        epic_id created author todo_exists todo_path start_date parent
         start_date_is_fixed start_date_fixed start_date_from_milestones
         start_date_sourcing_milestone_title start_date_sourcing_milestone_dates
         due_date due_date_is_fixed due_date_fixed due_date_from_milestones due_date_sourcing_milestone_title
@@ -43,6 +47,11 @@ describe EpicsHelper do
         'username' => "@#{user.username}",
         'src' => 'icon_path'
       })
+      expect(meta_data['parent']).to eq({
+        'id' => parent_epic.id,
+        'title' => parent_epic.title,
+        'url' => "/groups/#{group.full_path}/-/epics/#{parent_epic.iid}"
+      })
       expect(meta_data['start_date']).to eq('2000-01-01')
       expect(meta_data['start_date_sourcing_milestone_title']).to eq(milestone1.title)
       expect(meta_data['start_date_sourcing_milestone_dates']['start_date']).to eq(milestone1.start_date.to_s)
@@ -76,7 +85,7 @@ describe EpicsHelper do
         meta_data = JSON.parse(data[:meta])
 
         expect(meta_data.keys).to match_array(%w[
-          epic_id created author todo_exists todo_path start_date
+          epic_id created author todo_exists todo_path start_date parent
           start_date_is_fixed start_date_fixed start_date_from_milestones
           start_date_sourcing_milestone_title start_date_sourcing_milestone_dates
           due_date due_date_is_fixed due_date_fixed due_date_from_milestones due_date_sourcing_milestone_title

ee/spec/javascripts/epics/epic_show/mock_data.js

@@ -40,6 +40,7 @@ export const contentProps = {
   markdownPreviewPath: '',
   markdownDocsPath: '',
   issueLinksEndpoint: '/',
+  epicLinksEndpoint: '/',
   groupPath: '',
   namespace: 'gitlab-org',
   labelsPath: '',
@@ -71,6 +72,15 @@ export const contentProps = {
   subscribed: true,
   todoExists: false,
   state: 'opened',
+  parent: {
+    id: 12,
+    startDateIsFixed: true,
+    startDate: '2018-12-01',
+    dueDateIsFixed: true,
+    dueDateFixed: '2019-12-31',
+    title: 'Sample Parent Epic',
+    url: `${gl.TEST_HOST}/groups/gitlab-org/-/epics/12`,
+  },
 };
 
 export const headerProps = {

ee/spec/javascripts/epics/sidebar/components/sidebar_app_spec.js

@@ -19,6 +19,7 @@ describe('epicSidebar', () => {
     labelsWebUrl,
     epicsWebUrl,
     labels,
+    parent,
     participants,
     subscribed,
     toggleSubscriptionPath,
@@ -55,6 +56,7 @@ describe('epicSidebar', () => {
     startDateSourcingMilestoneDates,
     dueDateSourcingMilestoneTitle,
     dueDateSourcingMilestoneDates,
+    parent,
     toggleSubscriptionPath,
     labelsPath,
     labelsWebUrl,
@@ -115,6 +117,47 @@ describe('epicSidebar', () => {
     ).toEqual('Jan 1, 2018');
   });
 
+  describe('parent epic', () => {
+    it('should render parent epic information in sidebar when `parent` is present', () => {
+      const parentEpicEl = vm.$el.querySelector('.block.parent-epic');
+
+      expect(parentEpicEl).not.toBeNull();
+      expect(parentEpicEl.querySelector('.collapse-truncated-title').innerText.trim()).toBe(
+        parent.title,
+      );
+
+      expect(parentEpicEl.querySelector('.value a').innerText.trim()).toBe(parent.title);
+    });
+
+    it('should render parent epic as `none` when `parent` is empty', done => {
+      vm.parent = {};
+
+      Vue.nextTick()
+        .then(() => {
+          const parentEpicEl = vm.$el.querySelector('.block.parent-epic');
+
+          expect(parentEpicEl.querySelector('.collapse-truncated-title').innerText.trim()).toBe(
+            'None',
+          );
+
+          expect(parentEpicEl.querySelector('.value .no-value').innerText.trim()).toBe('None');
+        })
+        .then(done)
+        .catch(done.fail);
+    });
+
+    it('should render parent epic information icon when sidebar is collapsed', () => {
+      const parentEpicElCollapsed = vm.$el.querySelector(
+        '.block.parent-epic .sidebar-collapsed-icon',
+      );
+
+      expect(parentEpicElCollapsed).not.toBeNull();
+      expect(parentEpicElCollapsed.querySelector('svg use').getAttribute('xlink:href')).toContain(
+        'epic',
+      );
+    });
+  });
+
   describe('computed prop', () => {
     const getComponent = (
       customPropsData = {

ee/spec/javascripts/issuable/related_issues/components/add_issuable_form_spec.js

 import $ from 'jquery';
 import Vue from 'vue';
-import eventHub from 'ee/related_issues/event_hub';
 import addIssuableForm from 'ee/related_issues/components/add_issuable_form.vue';
 
 const issuable1 = {
@@ -167,21 +166,7 @@ describe('AddIssuableForm', () => {
   });
 
   describe('methods', () => {
-    let addIssuableFormInputSpy;
-    let addIssuableFormBlurSpy;
-    let addIssuableFormSubmitSpy;
-    let addIssuableFormCancelSpy;
-
     beforeEach(() => {
-      addIssuableFormInputSpy = jasmine.createSpy('spy');
-      addIssuableFormBlurSpy = jasmine.createSpy('spy');
-      addIssuableFormSubmitSpy = jasmine.createSpy('spy');
-      addIssuableFormCancelSpy = jasmine.createSpy('spy');
-      eventHub.$on('addIssuableFormInput', addIssuableFormInputSpy);
-      eventHub.$on('addIssuableFormBlur', addIssuableFormBlurSpy);
-      eventHub.$on('addIssuableFormSubmit', addIssuableFormSubmitSpy);
-      eventHub.$on('addIssuableFormCancel', addIssuableFormCancelSpy);
-
       const el = document.createElement('div');
       // We need to append to body to get focus tests working
       document.body.appendChild(el);
@@ -198,13 +183,6 @@ describe('AddIssuableForm', () => {
       }).$mount(el);
     });
 
-    afterEach(() => {
-      eventHub.$off('addIssuableFormInput', addIssuableFormInputSpy);
-      eventHub.$off('addIssuableFormBlur', addIssuableFormBlurSpy);
-      eventHub.$off('addIssuableFormSubmit', addIssuableFormSubmitSpy);
-      eventHub.$off('addIssuableFormCancel', addIssuableFormCancelSpy);
-    });
-
     it('when clicking somewhere on the input wrapper should focus the input', done => {
       vm.onInputWrapperClick();
 
@@ -219,18 +197,19 @@ describe('AddIssuableForm', () => {
     });
 
     it('when filling in the input', () => {
-      expect(addIssuableFormInputSpy).not.toHaveBeenCalled();
-
+      spyOn(vm, '$emit');
       const newInputValue = 'filling in things';
       vm.$refs.input.value = newInputValue;
       vm.onInput();
 
-      expect(addIssuableFormInputSpy).toHaveBeenCalledWith(newInputValue, newInputValue.length);
+      expect(vm.$emit).toHaveBeenCalledWith('addIssuableFormInput', {
+        newValue: newInputValue,
+        caretPos: newInputValue.length,
+      });
     });
 
     it('when blurring the input', done => {
-      expect(addIssuableFormInputSpy).not.toHaveBeenCalled();
-
+      spyOn(vm, '$emit');
       const newInputValue = 'filling in things';
       vm.$refs.input.value = newInputValue;
       vm.onBlur();
@@ -238,7 +217,7 @@ describe('AddIssuableForm', () => {
       setTimeout(() => {
         Vue.nextTick(() => {
           expect(vm.$refs.issuableFormWrapper.classList.contains('focus')).toEqual(false);
-          expect(addIssuableFormBlurSpy).toHaveBeenCalledWith(newInputValue);
+          expect(vm.$emit).toHaveBeenCalledWith('addIssuableFormBlur', newInputValue);
 
           done();
         });
@@ -266,29 +245,25 @@ describe('AddIssuableForm', () => {
       setTimeout(() => {
         Vue.nextTick(() => {
           expect(vm.$refs.input.value).toEqual('');
-          expect(addIssuableFormInputSpy.calls.count()).toEqual(1);
-
           done();
         });
       });
     });
 
     it('when submitting pending issues', () => {
-      expect(addIssuableFormSubmitSpy).not.toHaveBeenCalled();
-
+      spyOn(vm, '$emit');
       const newInputValue = 'filling in things';
       vm.$refs.input.value = newInputValue;
       vm.onFormSubmit();
 
-      expect(addIssuableFormSubmitSpy).toHaveBeenCalledWith(newInputValue);
+      expect(vm.$emit).toHaveBeenCalledWith('addIssuableFormSubmit', newInputValue);
     });
 
     it('when canceling form to collapse', () => {
-      expect(addIssuableFormCancelSpy).not.toHaveBeenCalled();
-
+      spyOn(vm, '$emit');
       vm.onFormCancel();
 
-      expect(addIssuableFormCancelSpy).toHaveBeenCalled();
+      expect(vm.$emit).toHaveBeenCalledWith('addIssuableFormCancel');
     });
   });
 });

ee/spec/javascripts/issuable/related_issues/components/issue_item_spec.js

 import Vue from 'vue';
 import issueItem from 'ee/related_issues/components/issue_item.vue';
-import eventHub from 'ee/related_issues/event_hub';
 import mountComponent from 'spec/helpers/vue_mount_component_helper';
 import { defaultMilestone, defaultAssignees } from '../mock_data';
 
@@ -18,6 +17,7 @@ describe('issueItem', () => {
     createdAt: '2018-12-01T00:00:00.00Z',
     milestone: defaultMilestone,
     assignees: defaultAssignees,
+    eventNamespace: 'relatedIssue',
   };
 
   beforeEach(() => {
@@ -172,11 +172,10 @@ describe('issueItem', () => {
     });
 
     it('triggers onRemoveRequest when clicked', () => {
-      const spy = jasmine.createSpy('spy');
-      eventHub.$on('removeRequest', spy);
+      spyOn(vm, '$emit');
       removeBtn.click();
 
-      expect(spy).toHaveBeenCalled();
+      expect(vm.$emit).toHaveBeenCalledWith('relatedIssueRemoveRequest', props.idKey);
     });
   });
 });

ee/spec/javascripts/issuable/related_issues/components/issue_token_spec.js

 import Vue from 'vue';
-import eventHub from 'ee/related_issues/event_hub';
 import issueToken from 'ee/related_issues/components/issue_token.vue';
 
 describe('IssueToken', () => {
@@ -7,6 +6,7 @@ describe('IssueToken', () => {
   const displayReference = 'foo/bar#123';
   const title = 'some title';
   const pathIdSeparator = '#';
+  const eventNamespace = 'pendingIssuable';
   let IssueToken;
   let vm;
 
@@ -25,6 +25,7 @@ describe('IssueToken', () => {
       vm = new IssueToken({
         propsData: {
           idKey,
+          eventNamespace,
           displayReference,
           pathIdSeparator,
         },
@@ -46,6 +47,7 @@ describe('IssueToken', () => {
       vm = new IssueToken({
         propsData: {
           idKey,
+          eventNamespace,
           displayReference,
           pathIdSeparator,
           title,
@@ -65,6 +67,7 @@ describe('IssueToken', () => {
       vm = new IssueToken({
         propsData: {
           idKey,
+          eventNamespace,
           displayReference,
           pathIdSeparator,
           title,
@@ -84,6 +87,7 @@ describe('IssueToken', () => {
         vm = new IssueToken({
           propsData: {
             idKey,
+            eventNamespace,
             displayReference,
             pathIdSeparator,
             state: 'opened',
@@ -101,6 +105,7 @@ describe('IssueToken', () => {
         vm = new IssueToken({
           propsData: {
             idKey,
+            eventNamespace,
             displayReference,
             pathIdSeparator,
             state: 'reopened',
@@ -118,6 +123,7 @@ describe('IssueToken', () => {
         vm = new IssueToken({
           propsData: {
             idKey,
+            eventNamespace,
             displayReference,
             pathIdSeparator,
             state: 'closed',
@@ -137,6 +143,7 @@ describe('IssueToken', () => {
       vm = new IssueToken({
         propsData: {
           idKey,
+          eventNamespace,
           displayReference,
           pathIdSeparator,
           title,
@@ -160,6 +167,7 @@ describe('IssueToken', () => {
         vm = new IssueToken({
           propsData: {
             idKey,
+            eventNamespace,
             displayReference,
             pathIdSeparator,
           },
@@ -176,6 +184,7 @@ describe('IssueToken', () => {
         vm = new IssueToken({
           propsData: {
             idKey,
+            eventNamespace,
             displayReference,
             pathIdSeparator,
             canRemove: true,
@@ -190,29 +199,22 @@ describe('IssueToken', () => {
   });
 
   describe('methods', () => {
-    let removeRequestSpy;
-
     beforeEach(() => {
       vm = new IssueToken({
         propsData: {
           idKey,
+          eventNamespace,
           displayReference,
           pathIdSeparator,
         },
       }).$mount();
-      removeRequestSpy = jasmine.createSpy('spy');
-      eventHub.$on('removeRequest', removeRequestSpy);
-    });
-
-    afterEach(() => {
-      eventHub.$off('removeRequest', removeRequestSpy);
     });
 
     it('when getting checked', () => {
-      expect(removeRequestSpy).not.toHaveBeenCalled();
+      spyOn(vm, '$emit');
       vm.onRemoveRequest();
 
-      expect(removeRequestSpy).toHaveBeenCalled();
+      expect(vm.$emit).toHaveBeenCalledWith('pendingIssuableRemoveRequest', vm.idKey);
     });
   });
 });

ee/spec/javascripts/issuable/related_issues/components/related_issues_block_spec.js

 import Vue from 'vue';
-import eventHub from 'ee/related_issues/event_hub';
 import relatedIssuesBlock from 'ee/related_issues/components/related_issues_block.vue';
 
 import { issuable1, issuable2, issuable3, issuable4, issuable5 } from '../mock_data';
@@ -20,7 +19,11 @@ describe('RelatedIssuesBlock', () => {
 
   describe('with defaults', () => {
     beforeEach(() => {
-      vm = new RelatedIssuesBlock().$mount();
+      vm = new RelatedIssuesBlock({
+        propsData: {
+          pathIdSeparator: '#',
+        },
+      }).$mount();
     });
 
     it('unable to add new related issues', () => {
@@ -40,6 +43,7 @@ describe('RelatedIssuesBlock', () => {
     beforeEach(() => {
       vm = new RelatedIssuesBlock({
         propsData: {
+          pathIdSeparator: '#',
           isFetching: true,
         },
       }).$mount();
@@ -58,6 +62,7 @@ describe('RelatedIssuesBlock', () => {
     beforeEach(() => {
       vm = new RelatedIssuesBlock({
         propsData: {
+          pathIdSeparator: '#',
           canAdmin: true,
         },
       }).$mount();
@@ -72,6 +77,7 @@ describe('RelatedIssuesBlock', () => {
     beforeEach(() => {
       vm = new RelatedIssuesBlock({
         propsData: {
+          pathIdSeparator: '#',
           isFormVisible: true,
         },
       }).$mount();
@@ -86,6 +92,7 @@ describe('RelatedIssuesBlock', () => {
     beforeEach(() => {
       vm = new RelatedIssuesBlock({
         propsData: {
+          pathIdSeparator: '#',
           relatedIssues: [issuable1, issuable2],
         },
       }).$mount();
@@ -97,20 +104,13 @@ describe('RelatedIssuesBlock', () => {
   });
 
   describe('methods', () => {
-    let toggleAddRelatedIssuesFormSpy;
-
     beforeEach(() => {
       vm = new RelatedIssuesBlock({
         propsData: {
+          pathIdSeparator: '#',
           relatedIssues: [issuable1, issuable2, issuable3, issuable4, issuable5],
         },
       }).$mount();
-      toggleAddRelatedIssuesFormSpy = jasmine.createSpy('spy');
-      eventHub.$on('toggleAddRelatedIssuesForm', toggleAddRelatedIssuesFormSpy);
-    });
-
-    afterEach(() => {
-      eventHub.$off('toggleAddRelatedIssuesForm', toggleAddRelatedIssuesFormSpy);
     });
 
     it('reorder item correctly when an item is moved to the top', () => {
@@ -140,12 +140,5 @@ describe('RelatedIssuesBlock', () => {
       expect(beforeAfterIds.beforeId).toBe(3);
       expect(beforeAfterIds.afterId).toBe(5);
     });
-
-    it('when expanding add related issue form', () => {
-      expect(toggleAddRelatedIssuesFormSpy).not.toHaveBeenCalled();
-      vm.toggleAddRelatedIssuesForm();
-
-      expect(toggleAddRelatedIssuesFormSpy).toHaveBeenCalled();
-    });
   });
 });

ee/spec/javascripts/issuable/related_issues/components/related_issues_root_spec.js

@@ -300,7 +300,10 @@ describe('RelatedIssuesRoot', () => {
 
       it('fill in issue number reference and adds to pending related issues', () => {
         const input = '#123 ';
-        vm.onInput(input, input.length);
+        vm.onInput({
+          newValue: input,
+          caretPos: input.length,
+        });
 
         expect(vm.state.pendingReferences.length).toEqual(1);
         expect(vm.state.pendingReferences[0]).toEqual('#123');
@@ -308,7 +311,7 @@ describe('RelatedIssuesRoot', () => {
 
       it('fill in with full reference', () => {
         const input = 'asdf/qwer#444 ';
-        vm.onInput(input, input.length);
+        vm.onInput({ newValue: input, caretPos: input.length });
 
         expect(vm.state.pendingReferences.length).toEqual(1);
         expect(vm.state.pendingReferences[0]).toEqual('asdf/qwer#444');
@@ -317,7 +320,7 @@ describe('RelatedIssuesRoot', () => {
       it('fill in with issue link', () => {
         const link = 'http://localhost:3000/foo/bar/issues/111';
         const input = `${link} `;
-        vm.onInput(input, input.length);
+        vm.onInput({ newValue: input, caretPos: input.length });
 
         expect(vm.state.pendingReferences.length).toEqual(1);
         expect(vm.state.pendingReferences[0]).toEqual(link);
@@ -325,7 +328,7 @@ describe('RelatedIssuesRoot', () => {
 
       it('fill in with multiple references', () => {
         const input = 'asdf/qwer#444 #12 ';
-        vm.onInput(input, input.length);
+        vm.onInput({ newValue: input, caretPos: input.length });
 
         expect(vm.state.pendingReferences.length).toEqual(2);
         expect(vm.state.pendingReferences[0]).toEqual('asdf/qwer#444');
@@ -334,7 +337,7 @@ describe('RelatedIssuesRoot', () => {
 
       it('fill in with some invalid things', () => {
         const input = 'something random ';
-        vm.onInput(input, input.length);
+        vm.onInput({ newValue: input, caretPos: input.length });
 
         expect(vm.state.pendingReferences.length).toEqual(2);
         expect(vm.state.pendingReferences[0]).toEqual('something');
@@ -343,7 +346,7 @@ describe('RelatedIssuesRoot', () => {
 
       it('fill in invalid and some legit references', () => {
         const input = 'something random #123 ';
-        vm.onInput(input, input.length);
+        vm.onInput({ newValue: input, caretPos: input.length });
 
         expect(vm.state.pendingReferences.length).toEqual(3);
         expect(vm.state.pendingReferences[0]).toEqual('something');
@@ -353,7 +356,7 @@ describe('RelatedIssuesRoot', () => {
 
       it('keep reference piece in input while we are touching it', () => {
         const input = 'a #123 b ';
-        vm.onInput(input, 3);
+        vm.onInput({ newValue: input, caretPos: 3 });
 
         expect(vm.state.pendingReferences.length).toEqual(2);
         expect(vm.state.pendingReferences[0]).toEqual('a');

ee/spec/javascripts/sidebar/ee_sidebar_item_epic_spec.js

@@ -16,7 +16,9 @@ describe('sidebarItemEpic', () => {
     });
 
     const SidebarItemEpic = Vue.extend(sidebarItemEpic);
-    vm = mountComponent(SidebarItemEpic, {});
+    vm = mountComponent(SidebarItemEpic, {
+      initialEpic: null,
+    });
   });
 
   afterEach(() => {

ee/spec/models/epic_spec.rb

@@ -7,7 +7,9 @@ describe Epic do
     it { is_expected.to belong_to(:author).class_name('User') }
     it { is_expected.to belong_to(:assignee).class_name('User') }
     it { is_expected.to belong_to(:group) }
+    it { is_expected.to belong_to(:parent) }
     it { is_expected.to have_many(:epic_issues) }
+    it { is_expected.to have_many(:children) }
   end
 
   describe 'validations' do
@@ -77,6 +79,36 @@ describe Epic do
     end
   end
 
+  describe '#ancestors', :nested_groups do
+    let(:group) { create(:group) }
+    let(:epic1) { create(:epic, group: group) }
+    let(:epic2) { create(:epic, group: group, parent: epic1) }
+    let(:epic3) { create(:epic, group: group, parent: epic2) }
+
+    it 'returns all ancestors for an epic' do
+      expect(epic3.ancestors).to match_array([epic1, epic2])
+    end
+
+    it 'returns an empty array if an epic does not have any parent' do
+      expect(epic1.ancestors).to be_empty
+    end
+  end
+
+  describe '#descendants', :nested_groups do
+    let(:group) { create(:group) }
+    let(:epic1) { create(:epic, group: group) }
+    let(:epic2) { create(:epic, group: group, parent: epic1) }
+    let(:epic3) { create(:epic, group: group, parent: epic2) }
+
+    it 'returns all ancestors for an epic' do
+      expect(epic1.descendants).to match_array([epic2, epic3])
+    end
+
+    it 'returns an empty array if an epic does not have any descendants' do
+      expect(epic3.descendants).to be_empty
+    end
+  end
+
   describe '#upcoming?' do
     it 'returns true when start_date is in the future' do
       epic = build(:epic, start_date: 1.month.from_now)

ee/spec/models/namespace_spec.rb

@@ -188,7 +188,7 @@ describe Namespace do
           end
         end
 
-        if Group.supports_nested_groups?
+        if Group.supports_nested_objects?
           context 'when license is applied to parent group' do
             let(:child_group) { create :group, parent: group }
 

ee/spec/services/epic_links/create_service_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe EpicLinks::CreateService, :postgresql do
+  describe '#execute' do
+    let(:group) { create(:group) }
+    let(:user) { create(:user) }
+    let(:epic) { create(:epic, group: group) }
+    let(:epic_to_add) { create(:epic, group: group) }
+
+    let(:valid_reference) { epic_to_add.to_reference(full: true) }
+
+    shared_examples 'returns success' do
+      it 'creates a new relationship and updates epic' do
+        expect { subject }.to change { epic.children.count }.by(1)
+
+        expect(epic.reload.children).to include(epic_to_add)
+      end
+
+      it 'returns success status' do
+        expect(subject).to eq(status: :success)
+      end
+    end
+
+    shared_examples 'returns not found error' do
+      it 'returns an error' do
+        expect(subject).to eq(message: 'No Epic found for given params', status: :error, http_status: 404)
+      end
+
+      it 'no relationship is created' do
+        expect { subject }.not_to change { epic.children.count }
+      end
+    end
+
+    def add_epic(references)
+      params = { issuable_references: references }
+
+      described_class.new(epic, user, params).execute
+    end
+
+    context 'when epics feature is disabled' do
+      subject { add_epic([valid_reference]) }
+
+      include_examples 'returns not found error'
+    end
+
+    context 'when epics feature is enabled' do
+      before do
+        stub_licensed_features(epics: true)
+      end
+
+      context 'when user has permissions to link the issue' do
+        before do
+          group.add_developer(user)
+        end
+
+        context 'when the reference list is empty' do
+          subject { add_epic([]) }
+
+          include_examples 'returns not found error'
+        end
+
+        context 'when a correct reference is given' do
+          subject { add_epic([valid_reference]) }
+
+          include_examples 'returns success'
+        end
+
+        context 'when an epic from a subgroup is given' do
+          let(:subgroup) { create(:group, parent: group) }
+
+          before do
+            epic_to_add.update!(group: subgroup)
+          end
+
+          subject { add_epic([valid_reference]) }
+
+          include_examples 'returns success'
+        end
+
+        context 'when an epic from a another group is given' do
+          let(:other_group) { create(:group) }
+
+          before do
+            epic_to_add.update!(group: other_group)
+          end
+
+          subject { add_epic([valid_reference]) }
+
+          include_examples 'returns not found error'
+        end
+
+        context 'when multiple valid epics are given' do
+          let(:another_epic) { create(:epic, group: group) }
+
+          subject do
+            add_epic(
+              [epic_to_add.to_reference(full: true), another_epic.to_reference(full: true)]
+            )
+          end
+
+          it 'creates new relationships' do
+            expect { subject }.to change { epic.children.count }.by(2)
+
+            expect(epic.reload.children).to match_array([epic_to_add, another_epic])
+          end
+
+          it 'returns success status' do
+            expect(subject).to eq(status: :success)
+          end
+        end
+
+        context 'when at least one epic is still not assigned to the parent epic' do
+          let(:another_epic) { create(:epic, group: group) }
+
+          before do
+            epic_to_add.update(parent: epic)
+          end
+
+          subject do
+            add_epic(
+              [epic_to_add.to_reference(full: true), another_epic.to_reference(full: true)]
+            )
+          end
+
+          it 'creates new relationships' do
+            expect { subject }.to change { epic.children.count }.from(1).to(2)
+
+            expect(epic.reload.children).to match_array([epic_to_add, another_epic])
+          end
+
+          it 'returns success status' do
+            expect(subject).to eq(status: :success)
+          end
+        end
+
+        context 'when adding an epic that is already a child of the parent epic' do
+          before do
+            epic_to_add.update(parent: epic)
+          end
+
+          subject { add_epic([valid_reference]) }
+
+          it 'returns an error' do
+            expect(subject).to eq(message: 'Epic(s) already assigned', status: :error, http_status: 409)
+          end
+
+          it 'no relationship is created' do
+            expect { subject }.not_to change { epic.children.count }
+          end
+        end
+
+        context 'when adding an epic would would exceed level 5 in hierarchy' do
+          context 'when adding to already deep structure' do
+            before do
+              epic1 = create(:epic, group: group)
+              epic2 = create(:epic, group: group, parent: epic1)
+              epic3 = create(:epic, group: group, parent: epic2)
+              epic4 = create(:epic, group: group, parent: epic3)
+
+              epic.update(parent: epic4)
+            end
+
+            subject { add_epic([valid_reference]) }
+
+            it 'returns an error' do
+              expect(subject).to eq(message: 'Epic hierarchy level too deep', status: :error, http_status: 409)
+            end
+
+            it 'no relationship is created' do
+              expect { subject }.not_to change { epic.children.count }
+            end
+          end
+
+          context 'when adding an epic already having some epics as children' do
+            before do
+              epic1 = create(:epic, group: group)
+
+              epic.update(parent: epic1) # epic is on level 2
+
+              # epic_to_add has 3 children (level 4 inlcuding epic_to_add)
+              # that would mean level 6 after relating epic_to_add on epic
+              epic2 = create(:epic, group: group, parent: epic_to_add)
+              epic3 = create(:epic, group: group, parent: epic2)
+              create(:epic, group: group, parent: epic3)
+            end
+
+            subject { add_epic([valid_reference]) }
+
+            include_examples 'returns not found error'
+          end
+        end
+
+        context 'when an epic is already assigned to another epic' do
+          let(:another_epic) { create(:epic, group: group) }
+
+          before do
+            epic_to_add.update(parent: another_epic)
+          end
+
+          subject { add_epic([valid_reference]) }
+
+          include_examples 'returns success'
+        end
+      end
+    end
+  end
+end

ee/spec/services/epic_links/list_service_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe EpicLinks::ListService, :postgresql do
+  let(:user) { create :user }
+  let(:group) { create(:group, :public) }
+  let(:parent_epic) { create(:epic, group: group) }
+
+  let!(:epic1) { create :epic, group: group, parent: parent_epic }
+  let!(:epic2) { create :epic, group: group, parent: parent_epic }
+
+  def epics_to_results(epics)
+    epics.map do |epic|
+      {
+        id: epic.id,
+        title: epic.title,
+        state: epic.state,
+        reference: epic.to_reference(group),
+        path: "/groups/#{epic.group.full_path}/-/epics/#{epic.iid}",
+        relation_path: "/groups/#{epic.group.full_path}/-/epics/#{parent_epic.iid}/links/#{epic.id}"
+      }
+    end
+  end
+
+  describe '#execute' do
+    subject { described_class.new(parent_epic, user).execute }
+
+    context 'when epics feature is disabled' do
+      it 'returns an empty array' do
+        group.add_developer(user)
+
+        expect(subject).to be_empty
+      end
+    end
+
+    context 'when epics feature is enabled' do
+      before do
+        stub_licensed_features(epics: true)
+      end
+
+      context 'group member can see all child epics' do
+        before do
+          group.add_developer(user)
+        end
+
+        it 'returns related issues JSON' do
+          expected_result = epics_to_results([epic1, epic2])
+
+          expect(subject).to match_array(expected_result)
+        end
+      end
+
+      context 'with nested groups' do
+        let(:subgroup1) { create(:group, :private, parent: group) }
+        let(:subgroup2) { create(:group, :private, parent: group) }
+        let!(:epic_subgroup1) { create :epic, group: subgroup1, parent: parent_epic }
+        let!(:epic_subgroup2) { create :epic, group: subgroup2, parent: parent_epic }
+
+        it 'returns all child epics for a group member' do
+          group.add_developer(user)
+
+          expected_result = epics_to_results([epic1, epic2, epic_subgroup1, epic_subgroup2])
+
+          expect(subject).to match_array(expected_result)
+        end
+
+        it 'returns only some child epics for a subgroup member' do
+          subgroup2.add_developer(user)
+
+          expected_result = epics_to_results([epic1, epic2, epic_subgroup2])
+
+          expect(subject).to match_array(expected_result)
+        end
+      end
+    end
+  end
+end

lib/gitlab/object_hierarchy.rb

@@ -45,7 +45,7 @@ module Gitlab
     end
     # rubocop: enable CodeReuse/ActiveRecord
 
-    # Returns a relation that includes the ancestors_base set of groups
+    # Returns a relation that includes the ancestors_base set of objects
     # and all their ancestors (recursively).
     #
     # Passing an `upto` will stop the recursion once the specified parent_id is

locale/gitlab.pot

@@ -6186,6 +6186,9 @@ msgstr ""
 msgid "Pagination|« First"
 msgstr ""
 
+msgid "Parent epic"
+msgstr ""
+
 msgid "Part of merge request changes"
 msgstr ""
 

spec/helpers/issuables_helper_spec.rb

@@ -197,32 +197,6 @@ describe IssuablesHelper do
       }
       expect(helper.issuable_initial_data(issue)).to eq(expected_data)
     end
-
-    it 'returns the correct data for an epic' do
-      epic = create(:epic, author: user, description: 'epic text')
-      @group = epic.group
-
-      expected_data = {
-        endpoint: "/groups/#{@group.full_path}/-/epics/#{epic.iid}",
-        updateEndpoint: "/groups/#{@group.full_path}/-/epics/#{epic.iid}.json",
-        issueLinksEndpoint: "/groups/#{@group.full_path}/-/epics/#{epic.iid}/issues",
-        canUpdate: true,
-        canDestroy: true,
-        canAdmin: true,
-        issuableRef: "&#{epic.iid}",
-        markdownPreviewPath: "/groups/#{@group.full_path}/preview_markdown",
-        markdownDocsPath: '/help/user/markdown',
-        markdownVersion: CacheMarkdownField::CACHE_COMMONMARK_VERSION,
-        issuableTemplates: nil,
-        groupPath: @group.path,
-        initialTitleHtml: epic.title,
-        initialTitleText: epic.title,
-        initialDescriptionHtml: '<p dir="auto">epic text</p>',
-        initialDescriptionText: 'epic text',
-        initialTaskStatus: '0 of 0 tasks completed'
-      }
-      expect(helper.issuable_initial_data(epic)).to eq(expected_data)
-    end
   end
 
   describe '#selected_labels' do

spec/lib/gitlab/object_hierarchy_spec.rb

@@ -119,7 +119,7 @@ describe Gitlab::ObjectHierarchy, :postgresql do
     end
   end
 
-  describe '#all_groups' do
+  describe '#all_objects' do
     let(:relation) do
       described_class.new(Group.where(id: child1.id)).all_objects
     end