Line items report whether they have tax included

app/models/spree/line_item_decorator.rb

@@ -33,6 +33,10 @@ Spree::LineItem.class_eval do
                       where('spree_adjustments.id IS NULL')
 
 
+  def has_tax?
+    adjustments.included_tax.any?
+  end
+
   def price_with_adjustments
     # EnterpriseFee#create_locked_adjustment applies adjustments on line items to their parent order,
     # so line_item.adjustments returns an empty array

spec/models/spree/line_item_spec.rb

@@ -63,5 +63,20 @@ module Spree
         li.amount_with_adjustments.should == 122.22
       end
     end
+
+    describe "checking if a line item has tax included" do
+      let(:li_no_tax)   { create(:line_item) }
+      let(:li_tax)      { create(:line_item) }
+      let(:tax_rate)    { create(:tax_rate, calculator: Spree::Calculator::DefaultTax.new) }
+      let!(:adjustment) { create(:adjustment, adjustable: li_tax, originator: tax_rate, label: "TR", amount: 123, included_tax: 10.00) }
+
+      it "returns true when it does" do
+        li_tax.should have_tax
+      end
+
+      it "returns false otherwise" do
+        li_no_tax.should_not have_tax
+      end
+    end
   end
 end