Search epics by state in the finder

- add by_state filter to the epics finder
- support count by states

app/finders/issuable_finder.rb

@@ -128,7 +128,7 @@ class IssuableFinder
     labels_count = 1 if use_cte_for_search?
 
     finder.execute.reorder(nil).group(:state).count.each do |key, value|
-      counts[Array(key).last.to_sym] += value / labels_count
+      counts[count_key(key)] += value / labels_count
     end
 
     counts[:all] = counts.values.sum
@@ -297,6 +297,10 @@ class IssuableFinder
     klass.all
   end
 
+  def count_key(value)
+    Array(value).last.to_sym
+  end
+
   # rubocop: disable CodeReuse/ActiveRecord
   def by_scope(items)
     return items.none if current_user_related? && !current_user

ee/app/controllers/groups/epics_controller.rb

@@ -101,7 +101,7 @@ class Groups::EpicsController < Groups::ApplicationController
   # we need to override the default state which is opened for now because we don't have
   # states for epics and need all as default for navigation to work correctly (#4017)
   def set_default_state
-    params[:state] = 'all'
+    params[:state] = 'opened' if params[:state].blank?
   end
 
   def authorize_create_epic!

ee/app/finders/epics_finder.rb

@@ -11,28 +11,12 @@ class EpicsFinder < IssuableFinder
     items = by_search(items)
     items = by_author(items)
     items = by_timeframe(items)
+    items = by_state(items)
     items = by_label(items)
 
     sort(items)
   end
 
-  def row_count
-    count = execute.count
-
-    # When filtering by multiple labels, count returns a hash of
-    # records grouped by id - so we just have to get length of the Hash.
-    # Once we have state for epics, we can use default issuables row_count
-    # method.
-    count.is_a?(Hash) ? count.length : count
-  end
-
-  # we don't have states for epics for now this method (#4017)
-  def count_by_state
-    {
-      all: row_count
-    }
-  end
-
   def group
     return nil unless params[:group_id]
     return @group if defined?(@group)
@@ -53,6 +37,10 @@ class EpicsFinder < IssuableFinder
 
   private
 
+  def count_key(value)
+    Epic.states.invert[Array(value).last].to_sym
+  end
+
   # rubocop: disable CodeReuse/ActiveRecord
   def groups_user_can_read_epics(groups)
     groups = Gitlab::GroupPlansPreloader.new.preload(groups)

ee/changelogs/unreleased/7014-epic-status-tabs.yml

+---
+title: Add Open/Closed epics tabs in list view
+merge_request: 7424
+author:
+type: added

ee/spec/factories/epics.rb

@@ -13,6 +13,15 @@ FactoryBot.define do
       due_date_is_fixed true
     end
 
+    trait :opened do
+      state :opened
+    end
+
+    trait :closed do
+      state :closed
+      closed_at { Time.now }
+    end
+
     factory :labeled_epic do
       transient do
         labels []

ee/spec/finders/epics_finder_spec.rb

@@ -5,10 +5,10 @@ describe EpicsFinder do
   let(:search_user) { create(:user)  }
   let(:group) { create(:group, :private) }
   let(:another_group) { create(:group) }
-  let!(:epic1) { create(:epic, group: group, title: 'This is awesome epic', created_at: 1.week.ago) }
-  let!(:epic2) { create(:epic, group: group, created_at: 4.days.ago, author: user, start_date: 2.days.ago, end_date: 3.days.from_now) }
-  let!(:epic3) { create(:epic, group: group, description: 'not so awesome', start_date: 5.days.ago, end_date: 3.days.ago) }
-  let!(:epic4) { create(:epic, group: another_group) }
+  let!(:epic1) { create(:epic, :opened, group: group, title: 'This is awesome epic', created_at: 1.week.ago) }
+  let!(:epic2) { create(:epic, :opened, group: group, created_at: 4.days.ago, author: user, start_date: 2.days.ago, end_date: 3.days.from_now) }
+  let!(:epic3) { create(:epic, :closed, group: group, description: 'not so awesome', start_date: 5.days.ago, end_date: 3.days.ago) }
+  let!(:epic4) { create(:epic, :closed, group: another_group) }
 
   describe '#execute' do
     def epics(params = {})
@@ -106,6 +106,12 @@ describe EpicsFinder do
           end
         end
 
+        context 'by state' do
+          it 'returns all epics with given state' do
+            expect(epics(state: :closed)).to contain_exactly(epic3)
+          end
+        end
+
         context 'when subgroups are supported', :nested_groups do
           let(:subgroup) { create(:group, :private, parent: group) }
           let(:subgroup2) { create(:group, :private, parent: subgroup) }
@@ -184,4 +190,17 @@ describe EpicsFinder do
       expect(described_class.new(search_user, params).row_count).to eq(1)
     end
   end
+
+  describe '#count_by_state' do
+    before do
+      group.add_developer(search_user)
+      stub_licensed_features(epics: true)
+    end
+
+    it 'returns correct counts' do
+      results = described_class.new(search_user, group_id: group.id).count_by_state
+
+      expect(results).to eq('opened' => 2, 'closed' => 1, 'all' => 3)
+    end
+  end
 end