Add `epics_list` app

Adds `epics_list` app to render Epics list
by using `issuable_list` internally.

ee/app/assets/javascripts/epics_list/components/epics_list_empty_state.vue

+<script>
+import { GlEmptyState } from '@gitlab/ui';
+import { __ } from '~/locale';
+
+import { IssuableStates } from '~/issuable_list/constants';
+
+import { FilterStateEmptyMessage } from '../constants';
+
+export default {
+  components: {
+    GlEmptyState,
+  },
+  inject: ['emptyStatePath'],
+  props: {
+    currentState: {
+      type: String,
+      required: true,
+    },
+    epicsCount: {
+      type: Object,
+      required: true,
+    },
+  },
+  computed: {
+    emptyStateTitle() {
+      return this.epicsCount[IssuableStates.All]
+        ? FilterStateEmptyMessage[this.currentState]
+        : __(
+            'Epics let you manage your portfolio of projects more efficiently and with less effort',
+          );
+    },
+    showDescription() {
+      return !this.epicsCount[IssuableStates.All];
+    },
+  },
+};
+</script>
+
+<template>
+  <gl-empty-state :svg-path="emptyStatePath" :title="emptyStateTitle">
+    <template v-if="showDescription" #description>
+      {{ __('Track groups of issues that share a theme, across projects and milestones') }}
+    </template>
+  </gl-empty-state>
+</template>

ee/app/assets/javascripts/epics_list/components/epics_list_root.vue

+<script>
+import { GlButton, GlIcon } from '@gitlab/ui';
+
+import EpicsFilteredSearchMixin from 'ee/roadmap/mixins/filtered_search_mixin';
+
+import { s__, sprintf } from '~/locale';
+import createFlash from '~/flash';
+import { parsePikadayDate, dateInWords } from '~/lib/utils/datetime_utility';
+
+import IssuableList from '~/issuable_list/components/issuable_list_root.vue';
+
+import { IssuableListTabs, DEFAULT_PAGE_SIZE } from '~/issuable_list/constants';
+
+import groupEpics from '../queries/group_epics.query.graphql';
+
+import { EpicsSortOptions } from '../constants';
+
+import EpicsListEmptyState from './epics_list_empty_state.vue';
+
+export default {
+  IssuableListTabs,
+  EpicsSortOptions,
+  defaultPageSize: DEFAULT_PAGE_SIZE,
+  epicSymbol: '&',
+  components: {
+    GlButton,
+    GlIcon,
+    IssuableList,
+    EpicsListEmptyState,
+  },
+  mixins: [EpicsFilteredSearchMixin],
+  inject: [
+    'canCreateEpic',
+    'canBulkEditEpics',
+    'page',
+    'prev',
+    'next',
+    'initialState',
+    'initialSortBy',
+    'epicsCount',
+    'epicNewPath',
+    'groupFullPath',
+    'groupLabelsPath',
+    'groupMilestonesPath',
+    'emptyStatePath',
+  ],
+  apollo: {
+    epics: {
+      query: groupEpics,
+      variables() {
+        const queryVariables = {
+          groupPath: this.groupFullPath,
+          state: this.currentState,
+        };
+
+        if (this.prevPageCursor) {
+          queryVariables.prevPageCursor = this.prevPageCursor;
+          queryVariables.lastPageSize = this.$options.defaultPageSize;
+        } else if (this.nextPageCursor) {
+          queryVariables.nextPageCursor = this.nextPageCursor;
+          queryVariables.firstPageSize = this.$options.defaultPageSize;
+        } else {
+          queryVariables.firstPageSize = this.$options.defaultPageSize;
+        }
+
+        if (this.sortedBy) {
+          queryVariables.sortBy = this.sortedBy;
+        }
+
+        if (Object.keys(this.filterParams).length) {
+          Object.assign(queryVariables, {
+            ...this.filterParams,
+          });
+        }
+
+        return queryVariables;
+      },
+      update(data) {
+        const epicsRoot = data.group?.epics;
+
+        return {
+          list: epicsRoot?.nodes || [],
+          pageInfo: epicsRoot?.pageInfo || {},
+        };
+      },
+      error(error) {
+        createFlash({
+          message: s__('Epics|Something went wrong while fetching epics list.'),
+          captureError: true,
+          error,
+        });
+      },
+    },
+  },
+  props: {
+    initialFilterParams: {
+      type: Object,
+      required: false,
+      default: () => ({}),
+    },
+  },
+  data() {
+    return {
+      currentState: this.initialState,
+      currentPage: this.page,
+      prevPageCursor: this.prev,
+      nextPageCursor: this.next,
+      filterParams: this.initialFilterParams,
+      sortedBy: this.initialSortBy,
+      epics: {
+        list: [],
+        pageInfo: {},
+      },
+    };
+  },
+  computed: {
+    epicsListLoading() {
+      return this.$apollo.queries.epics.loading;
+    },
+    epicsListEmpty() {
+      return !this.$apollo.queries.epics.loading && !this.epics.list.length;
+    },
+    showPaginationControls() {
+      const { hasPreviousPage, hasNextPage } = this.epics.pageInfo;
+
+      // This explicit check is necessary as both the variables
+      // can also be `false` and we just want to ensure that they're present.
+      if (hasPreviousPage !== undefined || hasNextPage !== undefined) {
+        return Boolean(hasPreviousPage || hasNextPage);
+      }
+      return !this.epicsListEmpty;
+    },
+    previousPage() {
+      return Math.max(this.currentPage - 1, 0);
+    },
+    nextPage() {
+      const nextPage = this.currentPage + 1;
+      return nextPage >
+        Math.ceil(this.epicsCount[this.currentState] / this.$options.defaultPageSize)
+        ? null
+        : nextPage;
+    },
+  },
+  methods: {
+    epicTimeframe({ startDate, dueDate }) {
+      const start = startDate ? parsePikadayDate(startDate) : null;
+      const due = dueDate ? parsePikadayDate(dueDate) : null;
+
+      if (startDate && dueDate) {
+        const startDateInWords = dateInWords(
+          start,
+          true,
+          start.getFullYear() === due.getFullYear(),
+        );
+        const dueDateInWords = dateInWords(due, true);
+
+        return sprintf(s__('Epics|%{startDate} – %{dueDate}'), {
+          startDate: startDateInWords,
+          dueDate: dueDateInWords,
+        });
+      } else if (startDate && !dueDate) {
+        return sprintf(s__('Epics|%{startDate} – No due date'), {
+          startDate: dateInWords(start, true, false),
+        });
+      } else if (!startDate && dueDate) {
+        return sprintf(s__('Epics|No start date – %{dueDate}'), {
+          dueDate: dateInWords(due, true, false),
+        });
+      }
+      return '';
+    },
+    fetchEpicsBy(propsName, propValue) {
+      if (propsName === 'currentPage') {
+        const { startCursor, endCursor } = this.epics.pageInfo;
+
+        if (propValue > this.currentPage) {
+          this.prevPageCursor = '';
+          this.nextPageCursor = endCursor;
+        } else {
+          this.prevPageCursor = startCursor;
+          this.nextPageCursor = '';
+        }
+      } else if (propsName === 'currentState') {
+        this.currentPage = 1;
+        this.prevPageCursor = '';
+        this.nextPageCursor = '';
+      }
+      this[propsName] = propValue;
+    },
+    handleFilterEpics(filters) {
+      this.filterParams = this.getFilterParams(filters);
+    },
+  },
+};
+</script>
+
+<template>
+  <issuable-list
+    :namespace="groupFullPath"
+    :tabs="$options.IssuableListTabs"
+    :current-tab="currentState"
+    :tab-counts="epicsCount"
+    :search-input-placeholder="__('Search or filter results...')"
+    :search-tokens="getFilteredSearchTokens()"
+    :sort-options="$options.EpicsSortOptions"
+    :initial-filter-value="getFilteredSearchValue()"
+    :initial-sort-by="sortedBy"
+    :issuables="epics.list"
+    :issuables-loading="epicsListLoading"
+    :show-pagination-controls="showPaginationControls"
+    :show-discussions="true"
+    :default-page-size="$options.defaultPageSize"
+    :current-page="currentPage"
+    :previous-page="previousPage"
+    :next-page="nextPage"
+    :url-params="urlParams"
+    :issuable-symbol="$options.epicSymbol"
+    recent-searches-storage-key="epics"
+    @click-tab="fetchEpicsBy('currentState', $event)"
+    @page-change="fetchEpicsBy('currentPage', $event)"
+    @sort="fetchEpicsBy('sortedBy', $event)"
+    @filter="handleFilterEpics"
+  >
+    <template v-if="canCreateEpic || canBulkEditEpics" #nav-actions>
+      <gl-button v-if="canCreateEpic" category="primary" variant="success" :href="epicNewPath">{{
+        __('New epic')
+      }}</gl-button>
+    </template>
+    <template #timeframe="{ issuable }">
+      <gl-icon name="calendar" />
+      {{ epicTimeframe(issuable) }}
+    </template>
+    <template #empty-state>
+      <epics-list-empty-state :current-state="currentState" :epics-count="epicsCount" />
+    </template>
+  </issuable-list>
+</template>

ee/app/assets/javascripts/epics_list/constants.js

+import { __ } from '~/locale';
+import { AvailableSortOptions } from '~/issuable_list/constants';
+
+export const EpicsSortOptions = [
+  {
+    id: AvailableSortOptions.length + 10,
+    title: __('Start date'),
+    sortDirection: {
+      descending: 'start_date_desc',
+      ascending: 'start_date_asc',
+    },
+  },
+  {
+    id: AvailableSortOptions.length + 20,
+    title: __('Due date'),
+    sortDirection: {
+      descending: 'end_date_desc',
+      ascending: 'end_date_asc',
+    },
+  },
+];
+
+export const FilterStateEmptyMessage = {
+  opened: __('There are no open epics'),
+  closed: __('There are no closed epics'),
+};

ee/app/assets/javascripts/epics_list/epics_list_bundle.js

+import Vue from 'vue';
+import VueApollo from 'vue-apollo';
+
+import createDefaultClient from '~/lib/graphql';
+import {
+  urlParamsToObject,
+  parseBoolean,
+  convertObjectPropsToCamelCase,
+} from '~/lib/utils/common_utils';
+import { IssuableStates } from '~/issuable_list/constants';
+
+import EpicsListApp from './components/epics_list_root.vue';
+
+Vue.use(VueApollo);
+
+export default function initEpicsList({ mountPointSelector }) {
+  const mountPointEl = document.querySelector(mountPointSelector);
+
+  if (!mountPointEl) {
+    return null;
+  }
+
+  const apolloProvider = new VueApollo({
+    defaultClient: createDefaultClient(),
+  });
+
+  const {
+    page = 1,
+    prev = '',
+    next = '',
+    initialState = IssuableStates.Opened,
+    initialSortBy = 'start_date_desc',
+    canCreateEpic,
+    canBulkEditEpics,
+    epicsCountOpened,
+    epicsCountClosed,
+    epicsCountAll,
+    epicNewPath,
+    groupFullPath,
+    groupLabelsPath,
+    groupMilestonesPath,
+    emptyStatePath,
+  } = mountPointEl.dataset;
+
+  const rawFilterParams = urlParamsToObject(window.location.search);
+  const initialFilterParams = {
+    ...convertObjectPropsToCamelCase(rawFilterParams, {
+      dropKeys: ['scope', 'utf8', 'state', 'sort'], // These keys are unsupported/unnecessary
+    }),
+    // We shall put parsed value of `confidential` only
+    // when it is defined.
+    ...(rawFilterParams.confidential && {
+      confidential: parseBoolean(rawFilterParams.confidential),
+    }),
+  };
+
+  return new Vue({
+    el: mountPointEl,
+    apolloProvider,
+    provide: {
+      initialState,
+      initialSortBy,
+      prev,
+      next,
+      page: parseInt(page, 10),
+      canCreateEpic: parseBoolean(canCreateEpic),
+      canBulkEditEpics: parseBoolean(canBulkEditEpics),
+      epicsCount: {
+        [IssuableStates.Opened]: parseInt(epicsCountOpened, 10),
+        [IssuableStates.Closed]: parseInt(epicsCountClosed, 10),
+        [IssuableStates.All]: parseInt(epicsCountAll, 10),
+      },
+      epicNewPath,
+      groupFullPath,
+      groupLabelsPath,
+      groupMilestonesPath,
+      emptyStatePath,
+    },
+    render: (createElement) =>
+      createElement(EpicsListApp, {
+        props: {
+          initialFilterParams,
+        },
+      }),
+  });
+}

ee/app/assets/javascripts/epics_list/queries/group_epics.query.graphql

+#import "~/graphql_shared/fragments/author.fragment.graphql"
+#import "~/graphql_shared/fragments/label.fragment.graphql"
+#import "~/graphql_shared/fragments/pageInfo.fragment.graphql"
+
+query groupEpics(
+  $groupPath: ID!
+  $state: EpicState
+  $authorUsername: String
+  $labelName: [String!]
+  $milestoneTitle: String = ""
+  $confidential: Boolean
+  $sortBy: EpicSort
+  $firstPageSize: Int
+  $lastPageSize: Int
+  $prevPageCursor: String = ""
+  $nextPageCursor: String = ""
+) {
+  group(fullPath: $groupPath) {
+    epics(
+      state: $state
+      authorUsername: $authorUsername
+      labelName: $labelName
+      milestoneTitle: $milestoneTitle
+      confidential: $confidential
+      sort: $sortBy
+      first: $firstPageSize
+      last: $lastPageSize
+      after: $nextPageCursor
+      before: $prevPageCursor
+    ) {
+      nodes {
+        id
+        iid
+        title
+        createdAt
+        updatedAt
+        startDate
+        dueDate
+        webUrl
+        userDiscussionsCount
+        confidential
+        author {
+          ...Author
+        }
+        labels {
+          nodes {
+            ...Label
+          }
+        }
+      }
+      pageInfo {
+        ...PageInfo
+      }
+    }
+  }
+}

ee/app/assets/javascripts/pages/groups/epics/index/index.js

 import FilteredSearchTokenKeysEpics from 'ee/filtered_search/filtered_search_token_keys_epics';
 import initEpicCreateApp from 'ee/epic/epic_bundle';
+import initEpicsList from 'ee/epics_list/epics_list_bundle';
 import initFilteredSearch from '~/pages/search/init_filtered_search';
 import issuableInitBulkUpdateSidebar from '~/issuable_init_bulk_update_sidebar';
 
 const EPIC_BULK_UPDATE_PREFIX = 'epic_';
 
-initFilteredSearch({
-  page: 'epics',
-  isGroup: true,
-  isGroupDecendent: true,
-  useDefaultState: true,
-  filteredSearchTokenKeys: FilteredSearchTokenKeysEpics,
-  stateFiltersSelector: '.epics-state-filters',
-});
+if (gon.features.vueEpicsList) {
+  initEpicsList({
+    mountPointSelector: '#js-epics-list',
+  });
+} else {
+  initFilteredSearch({
+    page: 'epics',
+    isGroup: true,
+    isGroupDecendent: true,
+    useDefaultState: true,
+    filteredSearchTokenKeys: FilteredSearchTokenKeysEpics,
+    stateFiltersSelector: '.epics-state-filters',
+  });
 
-initEpicCreateApp(true);
+  initEpicCreateApp(true);
 
-issuableInitBulkUpdateSidebar.init(EPIC_BULK_UPDATE_PREFIX);
+  issuableInitBulkUpdateSidebar.init(EPIC_BULK_UPDATE_PREFIX);
+}

ee/app/views/groups/epics/index.html.haml

@@ -2,20 +2,37 @@
 
 - page_title _("Epics")
 
-.top-area
-  = render 'shared/issuable/epic_nav', type: :epics
-  .nav-controls
-    - if @can_bulk_update
-      = render_if_exists 'shared/issuable/bulk_update_button', type: :epics
-    - if can?(current_user, :create_epic, @group)
-      = link_to _('New epic'), new_group_epic_path(@group), class: 'btn btn-success gl-button', data: { qa_selector: 'new_epic_button' }
+- if Feature.enabled?(:vue_epics_list, @group)
+  #js-epics-list{ data: { can_create_epic: can?(current_user, :create_epic, @group).to_s,
+    can_bulk_edit_epics: @can_bulk_update.to_s,
+    page: params[:page],
+    prev: params[:prev],
+    next: params[:next],
+    initial_state: params[:state],
+    initial_sort_by: params[:sort],
+    epics_count: { opened: issuables_count_for_state(:epic, :opened),
+      closed: issuables_count_for_state(:epic, :closed),
+      all: issuables_count_for_state(:epic, :all) },
+    epic_new_path: new_group_epic_url(@group),
+    group_full_path: @group.full_path,
+    group_labels_path: group_labels_path(@group, format: :json),
+    group_milestones_path: group_milestones_path(@group, format: :json),
+    empty_state_path: image_path('illustrations/epics/list.svg') } }
+- else
+  .top-area
+    = render 'shared/issuable/epic_nav', type: :epics
+    .nav-controls
+      - if @can_bulk_update
+        = render_if_exists 'shared/issuable/bulk_update_button', type: :epics
+      - if can?(current_user, :create_epic, @group)
+        = link_to _('New epic'), new_group_epic_path(@group), class: 'btn btn-success gl-button', data: { qa_selector: 'new_epic_button' }
 
-= render 'shared/epic/search_bar', type: :epics
+  = render 'shared/epic/search_bar', type: :epics
 
-- if @can_bulk_update
-  = render_if_exists 'shared/issuable/group_bulk_update_sidebar', group: @group, type: :epics
+  - if @can_bulk_update
+    = render_if_exists 'shared/issuable/group_bulk_update_sidebar', group: @group, type: :epics
 
-- if @epics.to_a.any?
-  = render 'shared/epics'
-- else
-  = render 'shared/empty_states/epics'
+  - if @epics.to_a.any?
+    = render 'shared/epics'
+  - else
+    = render 'shared/empty_states/epics'

ee/spec/features/epics/epics_list_spec.rb

@@ -10,6 +10,7 @@ RSpec.describe 'epics list', :js do
     stub_licensed_features(epics: true)
     stub_feature_flags(unfiltered_epic_aggregates: false)
     stub_feature_flags(async_filtering: false)
+    stub_feature_flags(vue_epics_list: false)
 
     sign_in(user)
   end
@@ -212,4 +213,45 @@ RSpec.describe 'epics list', :js do
       end
     end
   end
+
+  context 'vue epics list' do
+    let!(:epic1) { create(:epic, group: group, start_date: '2020-12-15', end_date: '2021-1-15') }
+    let!(:epic2) { create(:epic, group: group, start_date: '2020-12-15') }
+    let!(:epic3) { create(:epic, group: group, end_date: '2021-1-15') }
+
+    before do
+      stub_feature_flags(vue_epics_list: true)
+      group.add_developer(user)
+
+      visit group_epics_path(group)
+
+      wait_for_requests
+    end
+
+    it 'renders epics list' do
+      page.within('.issuable-list-container') do
+        expect(page).to have_selector('.gl-tabs')
+        expect(page).to have_link('New epic')
+        expect(page).to have_selector('.vue-filtered-search-bar-container')
+        expect(page.find('.issuable-list')).to have_selector('li.issue', count: 3)
+      end
+    end
+
+    it 'renders epics item with metadata' do
+      page.within('.issuable-list-container .issuable-list') do
+        expect(page.all('.issuable-info-container')[0].find('.issue-title')).to have_content(epic2.title)
+        expect(page.all('.issuable-info-container')[0].find('.issuable-reference')).to have_content("&#{epic2.iid}")
+        expect(page.all('.issuable-info-container')[0].find('.issuable-authored')).to have_content('created')
+        expect(page.all('.issuable-info-container')[0].find('.issuable-authored')).to have_content("by #{epic2.author.name}")
+      end
+    end
+
+    it 'renders epic item timeframe' do
+      page.within('.issuable-list-container .issuable-list') do
+        expect(page.all('.issuable-info-container')[0].find('.issuable-info')).to have_content('Dec 15, 2020 – No due date')
+        expect(page.all('.issuable-info-container')[1].find('.issuable-info')).to have_content('Dec 15, 2020 – Jan 15, 2021')
+        expect(page.all('.issuable-info-container')[2].find('.issuable-info')).to have_content('No start date – Jan 15, 2021')
+      end
+    end
+  end
 end

ee/spec/features/epics/filtered_search/visual_tokens_spec.rb

@@ -16,6 +16,7 @@ RSpec.describe 'epics list', :js do
 
   before do
     stub_licensed_features(epics: true)
+    stub_feature_flags(vue_epics_list: false)
 
     sign_in(user)
 

ee/spec/frontend/epics_list/components/epics_list_empty_state_spec.js

+import { GlEmptyState } from '@gitlab/ui';
+import { mount } from '@vue/test-utils';
+
+import EpicsListEmptyState from 'ee/epics_list/components/epics_list_empty_state.vue';
+
+const createComponent = (props = {}) =>
+  mount(EpicsListEmptyState, {
+    provide: {
+      emptyStatePath: '/assets/illustrations/empty-state/epics.svg',
+    },
+    propsData: {
+      currentState: 'opened',
+      epicsCount: {
+        opened: 0,
+        closed: 0,
+        all: 0,
+      },
+      ...props,
+    },
+  });
+
+describe('EpicsListEmptyState', () => {
+  let wrapper;
+
+  beforeEach(() => {
+    wrapper = createComponent();
+  });
+
+  afterEach(() => {
+    wrapper.destroy();
+  });
+
+  describe('template', () => {
+    it('renders gl-empty-state component', () => {
+      const emptyStateEl = wrapper.find(GlEmptyState);
+
+      expect(emptyStateEl.exists()).toBe(true);
+      expect(emptyStateEl.props('svgPath')).toBe('/assets/illustrations/empty-state/epics.svg');
+    });
+
+    it('returns string "There are no open epics" when value of `currentState` prop is "opened" and group has some epics', async () => {
+      wrapper.setProps({
+        epicsCount: {
+          opened: 0,
+          closed: 2,
+          all: 2,
+        },
+      });
+
+      await wrapper.vm.$nextTick();
+
+      expect(wrapper.find('h1').text()).toBe('There are no open epics');
+    });
+
+    it('returns string "There are no archived epics" when value of `currenState` prop is "closed" and group has some epics', async () => {
+      wrapper.setProps({
+        currentState: 'closed',
+        epicsCount: {
+          opened: 2,
+          closed: 0,
+          all: 2,
+        },
+      });
+
+      await wrapper.vm.$nextTick();
+
+      expect(wrapper.find('h1').text()).toBe('There are no closed epics');
+    });
+
+    it('returns a generic string when group has no epics', () => {
+      expect(wrapper.find('h1').text()).toBe(
+        'Epics let you manage your portfolio of projects more efficiently and with less effort',
+      );
+    });
+
+    it('renders empty state description with default description when all epics count is not zero', async () => {
+      wrapper.setProps({
+        epicsCount: {
+          opened: 0,
+          closed: 0,
+          all: 0,
+        },
+      });
+
+      await wrapper.vm.$nextTick();
+
+      expect(wrapper.find('p').exists()).toBe(true);
+      expect(wrapper.find('p').text()).toContain(
+        'Track groups of issues that share a theme, across projects and milestones',
+      );
+    });
+
+    it('does not render empty state description when all epics count is zero', async () => {
+      wrapper.setProps({
+        epicsCount: {
+          opened: 1,
+          closed: 0,
+          all: 1,
+        },
+      });
+
+      await wrapper.vm.$nextTick();
+
+      expect(wrapper.find('p').exists()).toBe(false);
+    });
+  });
+});

ee/spec/frontend/epics_list/components/epics_list_root_spec.js

+import { shallowMount } from '@vue/test-utils';
+import { pick } from 'lodash';
+
+import { stubComponent } from 'helpers/stub_component';
+import EpicsListRoot from 'ee/epics_list/components/epics_list_root.vue';
+import { EpicsSortOptions } from 'ee/epics_list/constants';
+import { mockFormattedEpic } from 'ee_jest/roadmap/mock_data';
+import { mockAuthor, mockLabels } from 'jest/issuable_list/mock_data';
+
+import IssuableList from '~/issuable_list/components/issuable_list_root.vue';
+import { IssuableListTabs } from '~/issuable_list/constants';
+
+jest.mock('~/issuable_list/constants', () => ({
+  DEFAULT_PAGE_SIZE: 2,
+  IssuableListTabs: jest.requireActual('~/issuable_list/constants').IssuableListTabs,
+  AvailableSortOptions: jest.requireActual('~/issuable_list/constants').AvailableSortOptions,
+}));
+
+const mockRawEpic = {
+  ...pick(mockFormattedEpic, [
+    'title',
+    'createdAt',
+    'updatedAt',
+    'webUrl',
+    'userDiscussionsCount',
+    'confidential',
+  ]),
+  author: mockAuthor,
+  labels: {
+    nodes: mockLabels,
+  },
+  startDate: '2021-04-01',
+  dueDate: '2021-06-30',
+};
+
+const mockEpics = new Array(5)
+  .fill()
+  .map((_, i) => ({ ...mockRawEpic, id: i + 1, iid: (i + 1) * 10 }));
+
+const mockProvide = {
+  canCreateEpic: true,
+  canBulkEditEpics: true,
+  page: 1,
+  prev: '',
+  next: '',
+  initialState: 'opened',
+  initialSortBy: 'created_desc',
+  epicsCount: {
+    opened: 5,
+    closed: 0,
+    all: 5,
+  },
+  epicNewPath: '/groups/gitlab-org/-/epics/new',
+  groupFullPath: 'gitlab-org',
+  groupLabelsPath: '/gitlab-org/-/labels.json',
+  groupMilestonesPath: '/gitlab-org/-/milestone.json',
+  emptyStatePath: '/assets/illustrations/empty-state/epics.svg',
+};
+
+const mockPageInfo = {
+  startCursor: 'eyJpZCI6IjI1IiwiY3JlYXRlZF9hdCI6IjIwMjAtMDMtMzEgMTM6MzI6MTQgVVRDIn0',
+  endCursor: 'eyJpZCI6IjIxIiwiY3JlYXRlZF9hdCI6IjIwMjAtMDMtMzEgMTM6MzE6MTUgVVRDIn0',
+};
+
+const createComponent = ({
+  provide = mockProvide,
+  initialFilterParams = {},
+  epicsLoading = false,
+  epicsList = mockEpics,
+} = {}) =>
+  shallowMount(EpicsListRoot, {
+    propsData: {
+      initialFilterParams,
+    },
+    provide,
+    mocks: {
+      $apollo: {
+        queries: {
+          epics: {
+            loading: epicsLoading,
+            list: epicsList,
+            pageInfo: mockPageInfo,
+          },
+        },
+      },
+    },
+    stubs: {
+      IssuableList: stubComponent(IssuableList),
+    },
+  });
+
+describe('EpicsListRoot', () => {
+  let wrapper;
+
+  beforeEach(() => {
+    wrapper = createComponent();
+  });
+
+  afterEach(() => {
+    wrapper.destroy();
+  });
+
+  describe('methods', () => {
+    describe('epicTimeframe', () => {
+      it.each`
+        startDate     | dueDate        | returnValue
+        ${'2021-1-1'} | ${'2021-2-28'} | ${'Jan 1 – Feb 28, 2021'}
+        ${'2021-1-1'} | ${'2022-2-28'} | ${'Jan 1, 2021 – Feb 28, 2022'}
+        ${'2021-1-1'} | ${null}        | ${'Jan 1, 2021 – No due date'}
+        ${null}       | ${'2021-2-28'} | ${'No start date – Feb 28, 2021'}
+      `(
+        'returns string "$returnValue" when startDate is $startDate and dueDate is $dueDate',
+        ({ startDate, dueDate, returnValue }) => {
+          expect(
+            wrapper.vm.epicTimeframe({
+              startDate,
+              dueDate,
+            }),
+          ).toBe(returnValue);
+        },
+      );
+    });
+
+    describe('fetchEpicsBy', () => {
+      it('updates prevPageCursor and nextPageCursor values when provided propsName param is "currentPage"', async () => {
+        wrapper.setData({
+          epics: {
+            pageInfo: mockPageInfo,
+          },
+        });
+        wrapper.vm.fetchEpicsBy('currentPage', 2);
+
+        await wrapper.vm.$nextTick();
+
+        expect(wrapper.vm.prevPageCursor).toBe('');
+        expect(wrapper.vm.nextPageCursor).toBe(mockPageInfo.endCursor);
+        expect(wrapper.vm.currentPage).toBe(2);
+      });
+    });
+  });
+
+  describe('template', () => {
+    const getIssuableList = () => wrapper.find(IssuableList);
+
+    it('renders issuable-list component', async () => {
+      wrapper.setData({
+        filterParams: {
+          search: 'foo',
+        },
+      });
+
+      await wrapper.vm.$nextTick();
+
+      expect(getIssuableList().exists()).toBe(true);
+      expect(getIssuableList().props()).toMatchObject({
+        namespace: mockProvide.groupFullPath,
+        tabs: IssuableListTabs,
+        currentTab: 'opened',
+        tabCounts: mockProvide.epicsCount,
+        searchInputPlaceholder: 'Search or filter results...',
+        sortOptions: EpicsSortOptions,
+        initialFilterValue: ['foo'],
+        initialSortBy: 'created_desc',
+        urlParams: wrapper.vm.urlParams,
+        issuableSymbol: '&',
+        recentSearchesStorageKey: 'epics',
+      });
+    });
+
+    it.each`
+      hasPreviousPage | hasNextPage  | returnValue
+      ${true}         | ${undefined} | ${true}
+      ${undefined}    | ${true}      | ${true}
+      ${false}        | ${undefined} | ${false}
+      ${undefined}    | ${false}     | ${false}
+      ${false}        | ${false}     | ${false}
+      ${true}         | ${true}      | ${true}
+    `(
+      'sets showPaginationControls prop value as $returnValue when hasPreviousPage is $hasPreviousPage and hasNextPage is $hasNextPage within `epics.pageInfo`',
+      async ({ hasPreviousPage, hasNextPage, returnValue }) => {
+        wrapper.setData({
+          epics: {
+            pageInfo: {
+              hasPreviousPage,
+              hasNextPage,
+            },
+          },
+        });
+
+        await wrapper.vm.$nextTick();
+
+        expect(getIssuableList().props('showPaginationControls')).toBe(returnValue);
+      },
+    );
+
+    it('sets previousPage prop value a number representing previous page based on currentPage value', async () => {
+      wrapper.setData({
+        currentPage: 3,
+      });
+
+      await wrapper.vm.$nextTick();
+
+      expect(wrapper.vm.previousPage).toBe(2);
+    });
+
+    it('sets nextPage prop value a number representing next page based on currentPage value', async () => {
+      wrapper.setData({
+        currentPage: 1,
+        epicsCount: {
+          opened: 5,
+          closed: 0,
+          all: 5,
+        },
+      });
+
+      await wrapper.vm.$nextTick();
+
+      expect(getIssuableList().props('nextPage')).toBe(2);
+    });
+
+    it('sets nextPage prop value as `null` when currentPage is already last page', async () => {
+      wrapper.setData({
+        currentPage: 3,
+        epicsCount: {
+          opened: 5,
+          closed: 0,
+          all: 5,
+        },
+      });
+
+      await wrapper.vm.$nextTick();
+
+      expect(getIssuableList().props('nextPage')).toBeNull();
+    });
+  });
+});

ee/spec/frontend/roadmap/mock_data.js

@@ -179,6 +179,10 @@ export const mockRawEpic = {
   start_date: '2017-6-26',
   end_date: '2018-03-10',
   web_url: '/groups/gitlab-org/marketing/-/epics/2',
+  created_at: '2021-01-22T13:51:19Z',
+  updated_at: '2021-01-27T05:40:19Z',
+  user_discussions_count: 2,
+  confidential: false,
   descendantCounts: {
     openedEpics: 3,
     closedEpics: 2,
@@ -251,6 +255,10 @@ export const mockFormattedEpic = {
   endDateOutOfRange: false,
   webUrl: '/groups/gitlab-org/marketing/-/epics/2',
   newEpic: undefined,
+  createdAt: '2021-01-22T13:51:19Z',
+  updatedAt: '2021-01-27T05:40:19Z',
+  userDiscussionsCount: 2,
+  confidential: false,
   descendantWeightSum: {
     closedIssues: 3,
     openedIssues: 2,

locale/gitlab.pot

@@ -11544,6 +11544,12 @@ msgstr ""
 msgid "Epics, Issues, and Merge Requests"
 msgstr ""
 
+msgid "Epics|%{startDate} – %{dueDate}"
+msgstr ""
+
+msgid "Epics|%{startDate} – No due date"
+msgstr ""
+
 msgid "Epics|Add a new epic"
 msgstr ""
 
@@ -11571,6 +11577,9 @@ msgstr ""
 msgid "Epics|Leave empty to inherit from milestone dates"
 msgstr ""
 
+msgid "Epics|No start date – %{dueDate}"
+msgstr ""
+
 msgid "Epics|Remove epic"
 msgstr ""
 
@@ -11598,6 +11607,9 @@ msgstr ""
 msgid "Epics|Something went wrong while fetching child epics."
 msgstr ""
 
+msgid "Epics|Something went wrong while fetching epics list."
+msgstr ""
+
 msgid "Epics|Something went wrong while fetching group epics."
 msgstr ""
 
@@ -29404,6 +29416,9 @@ msgstr ""
 msgid "There are no charts configured for this page"
 msgstr ""
 
+msgid "There are no closed epics"
+msgstr ""
+
 msgid "There are no closed issues"
 msgstr ""
 
@@ -29428,6 +29443,9 @@ msgstr ""
 msgid "There are no matching files"
 msgstr ""
 
+msgid "There are no open epics"
+msgstr ""
+
 msgid "There are no open issues"
 msgstr ""