refact and add specs to stock locations helper

backend/app/helpers/spree/admin/stock_locations_helper.rb

@@ -4,9 +4,7 @@ module Spree
   module Admin
     module StockLocationsHelper
       def admin_stock_location_display_name(stock_location)
-        name_parts = [stock_location.admin_name, stock_location.name]
-        name_parts.delete_if(&:blank?)
-        name_parts.join(' / ')
+        [stock_location.admin_name, stock_location.name].compact.join(' / ')
       end
     end
   end

backend/spec/helpers/admin/stock_locations_helper_spec.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Spree::Admin::StockLocationsHelper, type: :helper do
+  describe "#admin_stock_location_display_name" do
+    subject { helper.admin_stock_location_display_name(stock_location) }
+
+    context "without admin_name" do
+      let(:stock_location) { create(:stock_location_with_items) }
+
+      it { is_expected.to eq "NY Warehouse" }
+    end
+
+    context "with admin_name" do
+      let(:stock_location) { create(:stock_location_with_items, admin_name: "solidus") }
+
+      it { is_expected.to eq "solidus / NY Warehouse" }
+    end
+  end
+end