Rename GroupHierarchy into ObjectHierarchy

- we now use the hierarchy class also for epics
- also rename supports_nested_groups? into supports_nested_objects?
  - move it to a concern

16 files changed, 39 insertions, 31 deletions

diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 6f0dc2a3a20..140a625d333 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -403,7 +403,7 @@ class ApplicationController < ActionController::Base
   end
 
   def manifest_import_enabled?
-    Group.supports_nested_groups? && Gitlab::CurrentSettings.import_sources.include?('manifest')
+    Group.supports_nested_objects? && Gitlab::CurrentSettings.import_sources.include?('manifest')
   end
 
   # U2F (universal 2nd factor) devices need a unique identifier for the application
diff --git a/app/controllers/concerns/group_tree.rb b/app/controllers/concerns/group_tree.rb
index 4f56346832c..e9a7d6a3152 100644
--- a/app/controllers/concerns/group_tree.rb
+++ b/app/controllers/concerns/group_tree.rb
@@ -32,14 +32,14 @@ module GroupTree
   def filtered_groups_with_ancestors(groups)
     filtered_groups = groups.search(params[:filter]).page(params[:page])
 
-    if Group.supports_nested_groups?
+    if Group.supports_nested_objects?
       # We find the ancestors by ID of the search results here.
       # Otherwise the ancestors would also have filters applied,
       # which would cause them not to be preloaded.
       #
       # Pagination needs to be applied before loading the ancestors to
       # make sure ancestors are not cut off by pagination.
-      Gitlab::GroupHierarchy.new(Group.where(id: filtered_groups.select(:id)))
+      Gitlab::ObjectHierarchy.new(Group.where(id: filtered_groups.select(:id)))
         .base_and_ancestors
     else
       filtered_groups
diff --git a/app/finders/group_descendants_finder.rb b/app/finders/group_descendants_finder.rb
index a9ce5be13f3..96a36db7ec8 100644
--- a/app/finders/group_descendants_finder.rb
+++ b/app/finders/group_descendants_finder.rb
@@ -112,7 +112,7 @@ class GroupDescendantsFinder
   # rubocop: disable CodeReuse/ActiveRecord
   def ancestors_of_groups(base_for_ancestors)
     group_ids = base_for_ancestors.except(:select, :sort).select(:id)
-    Gitlab::GroupHierarchy.new(Group.where(id: group_ids))
+    Gitlab::ObjectHierarchy.new(Group.where(id: group_ids))
       .base_and_ancestors(upto: parent_group.id)
   end
   # rubocop: enable CodeReuse/ActiveRecord
@@ -132,7 +132,7 @@ class GroupDescendantsFinder
   end
 
   def subgroups
-    return Group.none unless Group.supports_nested_groups?
+    return Group.none unless Group.supports_nested_objects?
 
     # When filtering subgroups, we want to find all matches withing the tree of
     # descendants to show to the user
@@ -183,7 +183,7 @@ class GroupDescendantsFinder
 
   # rubocop: disable CodeReuse/ActiveRecord
   def hierarchy_for_parent
-    @hierarchy ||= Gitlab::GroupHierarchy.new(Group.where(id: parent_group.id))
+    @hierarchy ||= Gitlab::ObjectHierarchy.new(Group.where(id: parent_group.id))
   end
   # rubocop: enable CodeReuse/ActiveRecord
 end
diff --git a/app/finders/groups_finder.rb b/app/finders/groups_finder.rb
index ea954f98220..0080123407d 100644
--- a/app/finders/groups_finder.rb
+++ b/app/finders/groups_finder.rb
@@ -46,7 +46,7 @@ class GroupsFinder < UnionFinder
     return [Group.all] if current_user&.full_private_access? && all_available?
 
     groups = []
-    groups << Gitlab::GroupHierarchy.new(groups_for_ancestors, groups_for_descendants).all_groups if current_user
+    groups << Gitlab::ObjectHierarchy.new(groups_for_ancestors, groups_for_descendants).all_objects if current_user
     groups << Group.unscoped.public_to_user(current_user) if include_public_groups?
     groups << Group.none if groups.empty?
     groups
@@ -66,7 +66,7 @@ class GroupsFinder < UnionFinder
       .groups
       .where('members.access_level >= ?', params[:min_access_level])
 
-    Gitlab::GroupHierarchy
+    Gitlab::ObjectHierarchy
       .new(groups)
       .base_and_descendants
   end
diff --git a/app/helpers/groups_helper.rb b/app/helpers/groups_helper.rb
index 866fc555856..4a9ed123161 100644
--- a/app/helpers/groups_helper.rb
+++ b/app/helpers/groups_helper.rb
@@ -126,7 +126,7 @@ module GroupsHelper
   end
 
   def supports_nested_groups?
-    Group.supports_nested_groups?
+    Group.supports_nested_objects?
   end
 
   private
diff --git a/app/models/ci/runner.rb b/app/models/ci/runner.rb
index 3e5cedf92b9..8249199e76f 100644
--- a/app/models/ci/runner.rb
+++ b/app/models/ci/runner.rb
@@ -66,7 +66,7 @@ module Ci
 
     scope :belonging_to_parent_group_of_project, -> (project_id) {
       project_groups = ::Group.joins(:projects).where(projects: { id: project_id })
-      hierarchy_groups = Gitlab::GroupHierarchy.new(project_groups).base_and_ancestors
+      hierarchy_groups = Gitlab::ObjectHierarchy.new(project_groups).base_and_ancestors
 
       joins(:groups).where(namespaces: { id: hierarchy_groups })
     }
diff --git a/app/models/concerns/descendant.rb b/app/models/concerns/descendant.rb
new file mode 100644
index 00000000000..4c436522122
--- /dev/null
+++ b/app/models/concerns/descendant.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Descendant
+  extend ActiveSupport::Concern
+
+  class_methods do
+    def supports_nested_objects?
+      Gitlab::Database.postgresql?
+    end
+  end
+end
diff --git a/app/models/group.rb b/app/models/group.rb
index 233747cc2c2..edac2444c4d 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -10,6 +10,7 @@ class Group < Namespace
   include Referable
   include SelectForProjectAuthorization
   include LoadedInGroupList
+  include Descendant
   include GroupDescendant
   include TokenAuthenticatable
   include WithUploads
@@ -63,10 +64,6 @@ class Group < Namespace
   after_update :path_changed_hook, if: :path_changed?
 
   class << self
-    def supports_nested_groups?
-      Gitlab::Database.postgresql?
-    end
-
     def sort_by_attribute(method)
       if method == 'storage_size_desc'
         # storage_size is a virtual column so we need to
diff --git a/app/models/namespace.rb b/app/models/namespace.rb
index 3c9b1d32a53..36de1c41b67 100644
--- a/app/models/namespace.rb
+++ b/app/models/namespace.rb
@@ -175,16 +175,16 @@ class Namespace < ActiveRecord::Base
 
   # Returns all ancestors, self, and descendants of the current namespace.
   def self_and_hierarchy
-    Gitlab::GroupHierarchy
+    Gitlab::ObjectHierarchy
       .new(self.class.where(id: id))
-      .all_groups
+      .all_objects
   end
 
   # Returns all the ancestors of the current namespaces.
   def ancestors
     return self.class.none unless parent_id
 
-    Gitlab::GroupHierarchy
+    Gitlab::ObjectHierarchy
       .new(self.class.where(id: parent_id))
       .base_and_ancestors
   end
@@ -192,27 +192,27 @@ class Namespace < ActiveRecord::Base
   # returns all ancestors upto but excluding the given namespace
   # when no namespace is given, all ancestors upto the top are returned
   def ancestors_upto(top = nil, hierarchy_order: nil)
-    Gitlab::GroupHierarchy.new(self.class.where(id: id))
+    Gitlab::ObjectHierarchy.new(self.class.where(id: id))
       .ancestors(upto: top, hierarchy_order: hierarchy_order)
   end
 
   def self_and_ancestors
     return self.class.where(id: id) unless parent_id
 
-    Gitlab::GroupHierarchy
+    Gitlab::ObjectHierarchy
       .new(self.class.where(id: id))
       .base_and_ancestors
   end
 
   # Returns all the descendants of the current namespace.
   def descendants
-    Gitlab::GroupHierarchy
+    Gitlab::ObjectHierarchy
       .new(self.class.where(parent_id: id))
       .base_and_descendants
   end
 
   def self_and_descendants
-    Gitlab::GroupHierarchy
+    Gitlab::ObjectHierarchy
       .new(self.class.where(id: id))
       .base_and_descendants
   end
@@ -293,7 +293,7 @@ class Namespace < ActiveRecord::Base
   end
 
   def force_share_with_group_lock_on_descendants
-    return unless Group.supports_nested_groups?
+    return unless Group.supports_nested_objects?
 
     # We can't use `descendants.update_all` since Rails will throw away the WITH
     # RECURSIVE statement. We also can't use WHERE EXISTS since we can't use
diff --git a/app/models/project.rb b/app/models/project.rb
index 67262ecce85..9156229a041 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -570,7 +570,7 @@ class Project < ActiveRecord::Base
   # returns all ancestor-groups upto but excluding the given namespace
   # when no namespace is given, all ancestors upto the top are returned
   def ancestors_upto(top = nil, hierarchy_order: nil)
-    Gitlab::GroupHierarchy.new(Group.where(id: namespace_id))
+    Gitlab::ObjectHierarchy.new(Group.where(id: namespace_id))
       .base_and_ancestors(upto: top, hierarchy_order: hierarchy_order)
   end
 
diff --git a/app/models/user.rb b/app/models/user.rb
index f20756d1cc3..fe63f1ce100 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -709,13 +709,13 @@ class User < ActiveRecord::Base
 
   # Returns the groups a user is a member of, either directly or through a parent group
   def membership_groups
-    Gitlab::GroupHierarchy.new(groups).base_and_descendants
+    Gitlab::ObjectHierarchy.new(groups).base_and_descendants
   end
 
   # Returns a relation of groups the user has access to, including their parent
   # and child groups (recursively).
   def all_expanded_groups
-    Gitlab::GroupHierarchy.new(groups).all_groups
+    Gitlab::ObjectHierarchy.new(groups).all_objects
   end
 
   def expanded_groups_requiring_two_factor_authentication
@@ -1153,7 +1153,7 @@ class User < ActiveRecord::Base
   end
 
   def manageable_groups
-    Gitlab::GroupHierarchy.new(owned_or_maintainers_groups).base_and_descendants
+    Gitlab::ObjectHierarchy.new(owned_or_maintainers_groups).base_and_descendants
   end
 
   def namespaces
diff --git a/app/policies/group_policy.rb b/app/policies/group_policy.rb
index d1264559438..f07bb188265 100644
--- a/app/policies/group_policy.rb
+++ b/app/policies/group_policy.rb
@@ -16,7 +16,7 @@ class GroupPolicy < BasePolicy
   condition(:maintainer) { access_level >= GroupMember::MAINTAINER }
   condition(:reporter) { access_level >= GroupMember::REPORTER }
 
-  condition(:nested_groups_supported, scope: :global) { Group.supports_nested_groups? }
+  condition(:nested_groups_supported, scope: :global) { Group.supports_nested_objects? }
 
   condition(:has_parent, scope: :subject) { @subject.has_parent? }
   condition(:share_with_group_locked, scope: :subject) { @subject.share_with_group_lock? }
diff --git a/app/services/ci/register_job_service.rb b/app/services/ci/register_job_service.rb
index 13321b2682e..6707a1363d0 100644
--- a/app/services/ci/register_job_service.rb
+++ b/app/services/ci/register_job_service.rb
@@ -118,7 +118,7 @@ module Ci
       # Workaround for weird Rails bug, that makes `runner.groups.to_sql` to return `runner_id = NULL`
       groups = ::Group.joins(:runner_namespaces).merge(runner.runner_namespaces)
 
-      hierarchy_groups = Gitlab::GroupHierarchy.new(groups).base_and_descendants
+      hierarchy_groups = Gitlab::ObjectHierarchy.new(groups).base_and_descendants
       projects = Project.where(namespace_id: hierarchy_groups)
         .with_group_runners_enabled
         .with_builds_enabled
diff --git a/app/services/groups/nested_create_service.rb b/app/services/groups/nested_create_service.rb
index 50d34d8cb91..f01f5656296 100644
--- a/app/services/groups/nested_create_service.rb
+++ b/app/services/groups/nested_create_service.rb
@@ -18,7 +18,7 @@ module Groups
         return namespace
       end
 
-      if group_path.include?('/') && !Group.supports_nested_groups?
+      if group_path.include?('/') && !Group.supports_nested_objects?
         raise 'Nested groups are not supported on MySQL'
       end
 
diff --git a/app/services/groups/transfer_service.rb b/app/services/groups/transfer_service.rb
index 5efa746dfb9..f64e327416a 100644
--- a/app/services/groups/transfer_service.rb
+++ b/app/services/groups/transfer_service.rb
@@ -40,7 +40,7 @@ module Groups
 
     def ensure_allowed_transfer
       raise_transfer_error(:group_is_already_root) if group_is_already_root?
-      raise_transfer_error(:database_not_supported) unless Group.supports_nested_groups?
+      raise_transfer_error(:database_not_supported) unless Group.supports_nested_objects?
       raise_transfer_error(:same_parent_as_current) if same_parent?
       raise_transfer_error(:invalid_policies) unless valid_policies?
       raise_transfer_error(:namespace_with_same_path) if namespace_with_same_path?
diff --git a/app/services/users/refresh_authorized_projects_service.rb b/app/services/users/refresh_authorized_projects_service.rb
index 23b63aaabdf..fe5a82e23fa 100644
--- a/app/services/users/refresh_authorized_projects_service.rb
+++ b/app/services/users/refresh_authorized_projects_service.rb
@@ -102,7 +102,7 @@ module Users
     end
 
     def fresh_authorizations
-      klass = if Group.supports_nested_groups?
+      klass = if Group.supports_nested_objects?
                 Gitlab::ProjectAuthorizations::WithNestedGroups
               else
                 Gitlab::ProjectAuthorizations::WithoutNestedGroups