Use correctly value for shipping tax

Oops, was grabbing the total shipping tax for the order and using that
as the tax, instead of grabbing the collectable tax from the breakdown.
That makes more sense.

2 files changed, 48 insertions, 39 deletions

diff --git a/lib/super_good/solidus_taxjar/tax_calculator.rb b/lib/super_good/solidus_taxjar/tax_calculator.rb
index 4efa367..445087a 100644
--- a/lib/super_good/solidus_taxjar/tax_calculator.rb
+++ b/lib/super_good/solidus_taxjar/tax_calculator.rb
@@ -12,6 +12,7 @@ module SuperGood
 
       def calculate
         return no_tax if order.tax_address.empty?
+        return no_tax unless taxjar_breakdown
 
         Spree::Tax::OrderTax.new(
           order_id: order.id,
@@ -26,24 +27,22 @@ module SuperGood
 
       def line_item_taxes
         @line_item_taxes ||=
-          if taxjar_breakdown
-            taxjar_breakdown.line_items.map do |line_item|
-              Spree::Tax::ItemTax.new(
-                item_id: line_item.id.to_i,
-                label: "Sales Tax",
-                tax_rate: tax_rate,
-                amount: line_item.tax_collectable,
-                included_in_price: false
-              )
-            end
-          else
-            []
+          taxjar_breakdown.line_items.map do |line_item|
+            Spree::Tax::ItemTax.new(
+              item_id: line_item.id.to_i,
+              label: "Sales Tax",
+              tax_rate: tax_rate,
+              amount: line_item.tax_collectable,
+              included_in_price: false
+            )
           end
       end
 
       def shipment_taxes
         @shipment_taxes ||=
-          if (total_shipping_tax = taxjar_tax.shipping) != 0
+          if taxjar_breakdown.shipping? &&
+            (total_shipping_tax = taxjar_breakdown.shipping.tax_collectable) != 0
+
             # Distribute shipping tax across shipments:
             # TaxJar does not provide a breakdown of shipping taxes, so we have
             # to proportionally distribute the tax across the shipments,
diff --git a/spec/super_good/solidus_taxjar/tax_calculator_spec.rb b/spec/super_good/solidus_taxjar/tax_calculator_spec.rb
index b97f53b..bd74292 100644
--- a/spec/super_good/solidus_taxjar/tax_calculator_spec.rb
+++ b/spec/super_good/solidus_taxjar/tax_calculator_spec.rb
@@ -78,8 +78,7 @@ RSpec.describe ::SuperGood::SolidusTaxJar::TaxCalculator do
         allow(dummy_api).to receive(:tax_for).with(order).and_return(
           instance_double(
             ::Taxjar::Tax,
-            breakdown: breakdown,
-            shipping: shipping_tax
+            breakdown: breakdown
           )
         )
       end
@@ -93,18 +92,22 @@ RSpec.describe ::SuperGood::SolidusTaxJar::TaxCalculator do
           )
         end
 
-        let(:shipping_tax) { 10 }
-
         let(:breakdown) do
-          instance_double ::Taxjar::Breakdown, line_items: [taxjar_line_item]
+          instance_double ::Taxjar::Breakdown,
+            line_items: [taxjar_line_item],
+            shipping?: !!shipping_tax_breakdown,
+            shipping: shipping_tax_breakdown
         end
 
         let(:taxjar_line_item) do
           instance_double ::Taxjar::BreakdownLineItem, id: "33", tax_collectable: 6.66
         end
 
+        let(:shipping_tax_breakdown) { nil }
+
         it "returns the taxes" do
           expect(subject.order_id).to eq order.id
+          expect(subject.shipment_taxes).to be_empty
           expect(subject.line_item_taxes.length).to eq 1
 
           item_tax = subject.line_item_taxes.first
@@ -115,35 +118,42 @@ RSpec.describe ::SuperGood::SolidusTaxJar::TaxCalculator do
             expect(item_tax.amount).to eq 6.66
             expect(item_tax.included_in_price).to eq false
           end
+        end
 
-          shipment_taxes = subject.shipment_taxes
-          expect(shipment_taxes.length).to eq 3
+        context "when there are shipping taxes" do
+          let(:shipping_tax_breakdown) do
+            instance_double ::Taxjar::Shipping, tax_collectable: 10.00
+          end
 
-          aggregate_failures do
-            expect(shipment_taxes[0].item_id).to eq 1
-            expect(shipment_taxes[0].label).to eq "Sales Tax"
-            expect(shipment_taxes[0].tax_rate).to eq tax_rate
-            expect(shipment_taxes[0].amount).to eq 2.33
-            expect(shipment_taxes[0].included_in_price).to eq false
-
-            expect(shipment_taxes[1].item_id).to eq 2
-            expect(shipment_taxes[1].label).to eq "Sales Tax"
-            expect(shipment_taxes[1].tax_rate).to eq tax_rate
-            expect(shipment_taxes[1].amount).to eq 4.33
-            expect(shipment_taxes[1].included_in_price).to eq false
-
-            expect(shipment_taxes[2].item_id).to eq 3
-            expect(shipment_taxes[2].label).to eq "Sales Tax"
-            expect(shipment_taxes[2].tax_rate).to eq tax_rate
-            expect(shipment_taxes[2].amount).to eq 3.34
-            expect(shipment_taxes[2].included_in_price).to eq false
+          it "returns the shipping taxes" do
+            shipment_taxes = subject.shipment_taxes
+            expect(shipment_taxes.length).to eq 3
+
+            aggregate_failures do
+              expect(shipment_taxes[0].item_id).to eq 1
+              expect(shipment_taxes[0].label).to eq "Sales Tax"
+              expect(shipment_taxes[0].tax_rate).to eq tax_rate
+              expect(shipment_taxes[0].amount).to eq 2.33
+              expect(shipment_taxes[0].included_in_price).to eq false
+
+              expect(shipment_taxes[1].item_id).to eq 2
+              expect(shipment_taxes[1].label).to eq "Sales Tax"
+              expect(shipment_taxes[1].tax_rate).to eq tax_rate
+              expect(shipment_taxes[1].amount).to eq 4.33
+              expect(shipment_taxes[1].included_in_price).to eq false
+
+              expect(shipment_taxes[2].item_id).to eq 3
+              expect(shipment_taxes[2].label).to eq "Sales Tax"
+              expect(shipment_taxes[2].tax_rate).to eq tax_rate
+              expect(shipment_taxes[2].amount).to eq 3.34
+              expect(shipment_taxes[2].included_in_price).to eq false
+            end
           end
         end
       end
 
       context "and there is not a breakdown" do
         let(:breakdown) { nil }
-        let(:shipping_tax) { 0 }
 
         it "returns no taxes" do
           expect(subject.order_id).to eq order.id