4 files changed, 87 insertions, 15 deletions
diff --git a/app/finders/groups/accepting_group_transfers_finder.rb b/app/finders/groups/accepting_group_transfers_finder.rb
new file mode 100644
index 00000000000..df67f940d20
--- /dev/null
+++ b/app/finders/groups/accepting_group_transfers_finder.rb
@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+module Groups
+  class AcceptingGroupTransfersFinder < Base
+    include Gitlab::Utils::StrongMemoize
+
+    def initialize(current_user, group_to_be_transferred, params = {})
+      @current_user = current_user
+      @group_to_be_transferred = group_to_be_transferred
+      @params = params
+    end
+
+    def execute
+      return Group.none unless can_transfer_group?
+
+      items = if Feature.enabled?(:include_groups_from_group_shares_in_group_transfer_locations)
+                find_all_groups
+              else
+                find_groups
+              end
+
+      items = by_search(items)
+
+      sort(items)
+    end
+
+    private
+
+    attr_reader :current_user, :group_to_be_transferred, :params
+
+    def find_groups
+      GroupsFinder.new( # rubocop: disable CodeReuse/Finder
+        current_user,
+        min_access_level: Gitlab::Access::OWNER,
+        exclude_group_ids: exclude_groups
+      ).execute.without_order
+    end
+
+    def find_all_groups
+      ::Namespace.from_union(
+        [
+          find_groups,
+          groups_originating_from_group_shares_with_owner_access
+        ]
+      )
+    end
+
+    def groups_originating_from_group_shares_with_owner_access
+      GroupGroupLink
+        .with_owner_access
+        .groups_accessible_via(
+          current_user.owned_groups.select(:id)
+        ).id_not_in(exclude_groups)
+    end
+
+    def exclude_groups
+      strong_memoize(:exclude_groups) do
+        exclude_groups = group_to_be_transferred.self_and_descendants.pluck_primary_key
+        exclude_groups << group_to_be_transferred.parent_id if group_to_be_transferred.parent_id
+
+        exclude_groups
+      end
+    end
+
+    def can_transfer_group?
+      Ability.allowed?(current_user, :admin_group, group_to_be_transferred)
+    end
+  end
+end
diff --git a/app/finders/groups/accepting_project_transfers_finder.rb b/app/finders/groups/accepting_project_transfers_finder.rb
index 09d3c430641..a3f58a78eca 100644
--- a/app/finders/groups/accepting_project_transfers_finder.rb
+++ b/app/finders/groups/accepting_project_transfers_finder.rb
@@ -7,10 +7,6 @@ module Groups
     end
 
     def execute
-      if Feature.disabled?(:include_groups_from_group_shares_in_project_transfer_locations)
-        return current_user.manageable_groups
-      end
-
       groups_accepting_project_transfers =
         [
           current_user.manageable_groups,
diff --git a/app/finders/groups/base.rb b/app/finders/groups/base.rb
new file mode 100644
index 00000000000..d7f56b1a7a6
--- /dev/null
+++ b/app/finders/groups/base.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module Groups
+  class Base
+    private
+
+    def sort(items)
+      items.order(Group.arel_table[:path].asc, Group.arel_table[:id].asc) # rubocop: disable CodeReuse/ActiveRecord
+    end
+
+    def by_search(items)
+      return items if params[:search].blank?
+
+      items.search(params[:search], include_parents: true)
+    end
+  end
+end
diff --git a/app/finders/groups/user_groups_finder.rb b/app/finders/groups/user_groups_finder.rb
index bda8b7cc1e0..b58c1323b1f 100644
--- a/app/finders/groups/user_groups_finder.rb
+++ b/app/finders/groups/user_groups_finder.rb
@@ -13,7 +13,7 @@
 #
 # Initially created to filter user groups and descendants where the user can create projects
 module Groups
-  class UserGroupsFinder
+  class UserGroupsFinder < Base
     def initialize(current_user, target_user, params = {})
       @current_user = current_user
       @target_user = target_user
@@ -34,16 +34,6 @@ module Groups
 
     attr_reader :current_user, :target_user, :params
 
-    def sort(items)
-      items.order(Group.arel_table[:path].asc, Group.arel_table[:id].asc) # rubocop: disable CodeReuse/ActiveRecord
-    end
-
-    def by_search(items)
-      return items if params[:search].blank?
-
-      items.search(params[:search], include_parents: true)
-    end
-
     def by_permission_scope
       if permission_scope_create_projects?
         target_user.manageable_groups(include_groups_with_developer_maintainer_access: true)