Avoid raising unnecessary errors with incomplete address

When validating addresses, it may happen that the address
has no country, so trying to fetch the country ISO raises
an unnecessary error. Using ruby safe navigation prevents
this to happen. Of course, the address will still result
invalid eventually.

2 files changed, 20 insertions, 1 deletions

diff --git a/lib/super_good/solidus_taxjar/calculator_helper.rb b/lib/super_good/solidus_taxjar/calculator_helper.rb
index 89dedc0..636f322 100644
--- a/lib/super_good/solidus_taxjar/calculator_helper.rb
+++ b/lib/super_good/solidus_taxjar/calculator_helper.rb
@@ -17,7 +17,7 @@ module SuperGood
           address.city,
           address&.state&.abbr || address.state_name,
           address.zipcode,
-          address.country.iso
+          address.country&.iso
         ].any?(&:blank?)
       end
 
diff --git a/spec/super_good/solidus_taxjar/tax_rate_calculator_spec.rb b/spec/super_good/solidus_taxjar/tax_rate_calculator_spec.rb
index 9a4e2b8..3af89e5 100644
--- a/spec/super_good/solidus_taxjar/tax_rate_calculator_spec.rb
+++ b/spec/super_good/solidus_taxjar/tax_rate_calculator_spec.rb
@@ -12,6 +12,10 @@ RSpec.describe ::SuperGood::SolidusTaxJar::TaxRateCalculator do
 
     let(:dummy_tax_rate) { BigDecimal(0) }
 
+    let(:empty_address) do
+      ::Spree::Address.new
+    end
+
     let(:incomplete_address) do
       ::Spree::Address.new(
         first_name: "Ronnie James",
@@ -34,6 +38,21 @@ RSpec.describe ::SuperGood::SolidusTaxJar::TaxRateCalculator do
       it { expect(subject).to eq dummy_tax_rate }
     end
 
+    context "when the address is an empty address" do
+      let(:address) { empty_address }
+
+      context "when we're not rescuing from errors" do
+        around do |example|
+          handler = SuperGood::SolidusTaxJar.exception_handler
+          SuperGood::SolidusTaxJar.exception_handler = -> (error) { raise error }
+          example.run
+          SuperGood::SolidusTaxJar.exception_handler = handler
+        end
+
+        it_behaves_like "returns the dummy tax rate"
+      end
+    end
+
     context "when the address is not complete" do
       let(:address) { incomplete_address }