Increase epic max child hierarchy to seven

Increase the number of epics users can
nest under a parent epic from 5 to 7

doc/user/group/epics/index.md

@@ -96,7 +96,7 @@ New child epics appear at the top of the list of epics in the **Epics and Issues
 
 When you add an epic that's already linked to a parent epic, the link to its current parent is removed.
 
-An epic can have multiple child epics up to the maximum depth of five.
+An epic can have multiple child epics up to the maximum depth of seven.
 
 See [Manage multi-level child epics](manage_epics.md#manage-multi-level-child-epics) for
 steps to create, move, reorder, or delete child epics.

ee/app/models/ee/epic.rb

@@ -119,7 +119,7 @@ module EE
         public_only.or(where(confidential: true, group_id: groups))
       end
 
-      MAX_HIERARCHY_DEPTH = 5
+      MAX_HIERARCHY_DEPTH = 7
 
       def etag_caching_enabled?
         true

ee/changelogs/unreleased/issue_232665.yml

+---
+title: Increase the Epic Nesting from 5 to 7
+merge_request: 49619
+author:
+type: changed

ee/spec/features/epics/epic_issues_spec.rb

@@ -3,6 +3,7 @@
 require 'spec_helper'
 
 RSpec.describe 'Epic Issues', :js do
+  include NestedEpicsHelper
   include DragTo
 
   let(:user) { create(:user) }
@@ -195,13 +196,9 @@ RSpec.describe 'Epic Issues', :js do
         end
 
         context 'when epics are nested too deep' do
-          let(:epic1) { create(:epic, group: group, parent_id: epic.id) }
-          let(:epic2) { create(:epic, group: group, parent_id: epic1.id) }
-          let(:epic3) { create(:epic, group: group, parent_id: epic2.id) }
-          let(:epic4) { create(:epic, group: group, parent_id: epic3.id) }
-
           before do
-            visit group_epic_path(group, epic4)
+            last_child = add_children_to(epic: epic, count: 6)
+            visit group_epic_path(group, last_child)
 
             wait_for_requests
 
@@ -215,7 +212,7 @@ RSpec.describe 'Epic Issues', :js do
             add_epics(references)
 
             expect(page).to have_selector('.gl-field-error')
-            expect(find('.gl-field-error')).to have_text("This epic cannot be added. One or more epics would exceed the maximum depth (5) from its most distant ancestor.")
+            expect(find('.gl-field-error')).to have_text("This epic cannot be added. One or more epics would exceed the maximum depth (#{Epic::MAX_HIERARCHY_DEPTH}) from its most distant ancestor.")
           end
         end
       end

ee/spec/models/epic_spec.rb

@@ -3,6 +3,8 @@
 require 'spec_helper'
 
 RSpec.describe Epic do
+  include NestedEpicsHelper
+
   let_it_be(:user) { create(:user) }
   let_it_be(:group) { create(:group) }
   let(:project) { create(:project, group: group) }
@@ -185,31 +187,28 @@ RSpec.describe Epic do
 
       it 'returns false when level is too deep' 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)
-        epic5 = create(:epic, group: group, parent: epic4)
-        epic.parent = epic5
+        add_parents_to(epic: epic1, count: 6)
+
+        epic.parent = epic1
 
         expect(epic.valid_parent?).to be_falsey
       end
     end
 
     context 'when adding an Epic that has existing children' do
-      let(:parent_epic) { create(:epic, group: group) }
+      let_it_be(:parent_epic) { create(:epic, group: group) }
       let(:epic) { build(:epic, group: group) }
-      let(:child_epic1) { create(:epic, group: group, parent: epic)}
 
       it 'returns true when total depth after adding will not exceed limit' do
+        create(:epic, group: group, parent: epic)
+
         epic.parent = parent_epic
 
         expect(epic.valid_parent?).to be_truthy
       end
 
       it 'returns false when total depth after adding would exceed limit' do
-        child_epic2 = create(:epic, group: group, parent: child_epic1)
-        child_epic3 = create(:epic, group: group, parent: child_epic2)
-        create(:epic, group: group, parent: child_epic3)
+        add_children_to(epic: epic, count: 6)
 
         epic.parent = parent_epic
 
@@ -218,8 +217,8 @@ RSpec.describe Epic do
     end
 
     context 'when parent has ancestors and epic has children' do
-      let(:root_epic) { create(:epic, group: group) }
-      let(:parent_epic) { create(:epic, group: group, parent: root_epic) }
+      let_it_be(:root_epic) { create(:epic, group: group) }
+      let_it_be(:parent_epic) { create(:epic, group: group, parent: root_epic) }
       let(:epic) { build(:epic, group: group) }
       let(:child_epic1) { create(:epic, group: group, parent: epic)}
 
@@ -230,8 +229,8 @@ RSpec.describe Epic do
       end
 
       it 'returns false when total depth after adding would exceed limit' do
-        root_epic.update(parent: create(:epic, group: group))
-        create(:epic, group: group, parent: child_epic1)
+        add_parents_to(epic: root_epic, count: 2)
+        add_children_to(epic: child_epic1, count: 2)
 
         epic.parent = parent_epic
 

ee/spec/services/epic_links/create_service_spec.rb

@@ -3,6 +3,8 @@
 require 'spec_helper'
 
 RSpec.describe EpicLinks::CreateService do
+  include NestedEpicsHelper
+
   describe '#execute' do
     let(:group) { create(:group) }
     let(:user) { create(:user) }
@@ -148,34 +150,25 @@ RSpec.describe EpicLinks::CreateService do
 
             context 'when adding to an Epic that is already at maximum depth' 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)
+                add_parents_to(epic: epic, count: 6)
               end
 
-              let(:expected_error) { "This epic cannot be added. One or more epics would exceed the maximum depth (5) from its most distant ancestor." }
+              let(:expected_error) { "This epic cannot be added. One or more epics would exceed the maximum depth (#{Epic::MAX_HIERARCHY_DEPTH}) from its most distant ancestor." }
               let(:expected_code) { 409 }
 
               include_examples 'returns an error'
             end
 
             context 'when total depth after adding would exceed depth limit' do
-              let(:expected_error) { "This epic cannot be added. One or more epics would exceed the maximum depth (5) from its most distant ancestor." }
+              let(:expected_error) { "This epic cannot be added. One or more epics would exceed the maximum depth (#{Epic::MAX_HIERARCHY_DEPTH}) from its most distant ancestor." }
               let(:expected_code) { 409 }
 
               before do
-                epic1 = create(:epic, group: group)
+                add_parents_to(epic: epic, count: 1) # epic is on level 2
 
-                epic.update(parent: epic1) # epic is on level 2
-
-                # epic_to_add has 3 children (level 4 including 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)
+                # epic_to_add has 5 children (level 6 including epic_to_add)
+                # that would mean level 8 after relating epic_to_add on epic
+                add_children_to(epic: epic_to_add, count: 5)
               end
 
               include_examples 'returns an error'
@@ -215,15 +208,11 @@ RSpec.describe EpicLinks::CreateService do
 
             context 'when total depth after adding would exceed limit' do
               before do
-                epic1 = create(:epic, group: group)
-
-                epic.update(parent: epic1) # epic is on level 2
+                add_parents_to(epic: epic, count: 1) # epic is on level 2
 
-                # epic_to_add has 3 children (level 4 including 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)
+                # epic_to_add has 5 children (level 6 including epic_to_add)
+                # that would mean level 8 after relating epic_to_add on epic
+                add_children_to(epic: epic_to_add, count: 5)
               end
 
               let(:another_epic) { create(:epic) }

ee/spec/support/helpers/nested_epics_helper.rb

+# frozen_string_literal: true
+
+module NestedEpicsHelper
+  def add_parents_to(epic:, count:)
+    latest = nil
+
+    count.times do
+      latest = create(:epic, group: epic.group, parent: latest)
+    end
+
+    epic.update!(parent: latest)
+
+    latest
+  end
+
+  def add_children_to(epic:, count:)
+    latest = epic
+
+    count.times do
+      latest = create(:epic, group: epic.group, parent: latest)
+    end
+
+    latest
+  end
+end