1 files changed, 90 insertions, 0 deletions
diff --git a/spec/lib/gitlab/background_migration/nullify_creator_id_column_of_orphaned_projects_spec.rb b/spec/lib/gitlab/background_migration/nullify_creator_id_column_of_orphaned_projects_spec.rb
new file mode 100644
index 00000000000..a8574411957
--- /dev/null
+++ b/spec/lib/gitlab/background_migration/nullify_creator_id_column_of_orphaned_projects_spec.rb
@@ -0,0 +1,90 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::BackgroundMigration::NullifyCreatorIdColumnOfOrphanedProjects, feature_category: :projects do
+  let(:users) { table(:users) }
+  let(:projects) { table(:projects) }
+  let(:namespaces) { table(:namespaces) }
+
+  let(:user_1) { users.create!(name: 'user_1', email: 'user_1@example.com', projects_limit: 4) }
+  let(:user_2) { users.create!(name: 'user_2', email: 'user_2@example.com', projects_limit: 4) }
+  let(:user_3) { users.create!(name: 'user_3', email: 'user_3@example.com', projects_limit: 4) }
+
+  let!(:group) do
+    namespaces.create!(
+      name: 'Group1', type: 'Group', path: 'space1'
+    )
+  end
+
+  let!(:project_namespace_1) do
+    namespaces.create!(
+      name: 'project_1', path: 'project_1', type: 'Project'
+    )
+  end
+
+  let!(:project_namespace_2) do
+    namespaces.create!(
+      name: 'project_2', path: 'project_2', type: 'Project'
+    )
+  end
+
+  let!(:project_namespace_3) do
+    namespaces.create!(
+      name: 'project_3', path: 'project_3', type: 'Project'
+    )
+  end
+
+  let!(:project_namespace_4) do
+    namespaces.create!(
+      name: 'project_4', path: 'project_4', type: 'Project'
+    )
+  end
+
+  let!(:project_1) do
+    projects.create!(
+      name: 'project_1', path: 'project_1', namespace_id: group.id, project_namespace_id: project_namespace_1.id,
+      creator_id: user_1.id
+    )
+  end
+
+  let!(:project_2) do
+    projects.create!(
+      name: 'project_2', path: 'project_2', namespace_id: group.id, project_namespace_id: project_namespace_2.id,
+      creator_id: user_2.id
+    )
+  end
+
+  let!(:project_3) do
+    projects.create!(
+      name: 'project_3', path: 'project_3', namespace_id: group.id, project_namespace_id: project_namespace_3.id,
+      creator_id: user_3.id
+    )
+  end
+
+  let!(:project_4) do
+    projects.create!(
+      name: 'project_4', path: 'project_4', namespace_id: group.id, project_namespace_id: project_namespace_4.id,
+      creator_id: nil
+    )
+  end
+
+  subject do
+    described_class.new(
+      start_id: project_1.id,
+      end_id: project_4.id,
+      batch_table: :projects,
+      batch_column: :id,
+      sub_batch_size: 1,
+      pause_ms: 0,
+      connection: ApplicationRecord.connection
+    ).perform
+  end
+
+  it 'nullifies the `creator_id` column of projects whose creators do not exist' do
+    # `delete` `user_3` so that the creator of `project_3` is removed, without invoking `dependent: :nullify` on `User`
+    user_3.delete
+
+    expect { subject }.to change { projects.where(creator_id: nil).count }.from(1).to(2)
+  end
+end