Changes update_column to update_attributes in ProjectTreeRestorer#restore_project by using timeless to maintain the current timestamps

changelogs/unreleased/47765-group-visibility-error-due-to-string-conversion.yml

@@ -0,0 +1,6 @@
+---
+title: Importing a project no longer fails when visibility level holds a string value
+  type
+merge_request: 21242
+author:
+type: fixed

lib/gitlab/import_export/project_tree_restorer.rb

@@ -94,7 +94,10 @@ module Gitlab
       end
 
       def restore_project
-        @project.update_columns(project_params)
+        Gitlab::Timeless.timeless(@project) do
+          @project.update(project_params)
+        end
+
         @project
       end
 

spec/lib/gitlab/import_export/importer_spec.rb

@@ -63,6 +63,16 @@ describe Gitlab::ImportExport::Importer do
 
         importer.execute
       end
+
+      it 'sets the correct visibility_level when visibility level is a string' do
+        project.create_or_update_import_data(
+          data: { override_params: { visibility_level: Gitlab::VisibilityLevel::PRIVATE.to_s } }
+        )
+
+        importer.execute
+
+        expect(project.visibility_level).to eq(Gitlab::VisibilityLevel::PRIVATE)
+      end
     end
 
     context 'when project successfully restored' do