Rename Spree::ItemTotalUpdater to Spree::ItemTotal

Co-Authored-By: Harmony Evangelina <[email protected]>
Co-Authored-By: Jared Norman <[email protected]>
Co-Authored-By: Kendra Riga <[email protected]>
Co-Authored-By: Sofia Besenski <[email protected]>
Co-Authored-By: benjamin wil <[email protected]>

core/app/models/spree/item_total.rb

@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+class Spree::ItemTotal
+  def initialize(item)
+    @item = item
+  end
+
+  def recalculate!
+    item.adjustment_total = item.adjustments.reject(&:included?).sum(&:amount)
+  end
+
+  private
+
+  attr_reader :item
+end

core/spec/models/spree/item_total_spec.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Spree::ItemTotal do
+  describe "#recalculate!" do
+    subject { described_class.new(item).recalculate! }
+
+    let(:item) { create :line_item, adjustments: [adjustment] }
+    let(:adjustment) { create :adjustment, amount: 19.99 }
+
+    it "sets the adjustment total on the item" do
+      expect { subject }
+        .to change { item.adjustment_total }
+        .from(0).to(19.99)
+    end
+
+    it "does not factor in included adjustments" do
+      adjustment.update!(included: true)
+      expect { subject }.not_to change { item.adjustment_total }.from(0)
+    end
+  end
+end