test.rb

      describe '#customization_options' do
        before { class FooBar; end }

        it 'returns a placeholder when there are no customizations' do
          customizations = view_model.customization_options
          expect(customizations).to eq([['None', nil]])
        end

        it 'returns array of customization options' do
          allow(Weblinc.config).to receive(:customization_types).and_return([FooBar])
          customizations = view_model.customization_options
          expect(customizations).to eq([['None', nil], ['Foo Bar', 'weblinc/admin/foo_bar']])
        end

        after { Object.send(:remove_const, :FooBar) }
      end