Add errors for invalid input with number localization enabled

lib/spree/localized_number.rb

@@ -44,7 +44,7 @@ module Spree
 
     def self.valid_localizable_number?(number)
       return true unless number.is_a?(String) || number.respond_to?(:to_d)
-      return false if number.to_s =~ /[.,]\d{2}[.,]/
+      return false if number.to_s =~ /[.,]\d{2}[.,]/ || number.to_s =~ /[^0-9,.]+/
 
       true
     end

spec/lib/spree/localized_number_spec.rb

@@ -59,5 +59,11 @@ describe Spree::LocalizedNumber do
         expect(described_class.valid_localizable_number?(1599.99)).to eql true
       end
     end
+
+    context "with letters" do
+      it "returns false" do
+        expect(described_class.valid_localizable_number?('invalid')).to eql false
+      end
+    end
   end
 end

spec/models/concerns/nested_calculator_validation_spec.rb

@@ -45,4 +45,21 @@ shared_examples "a parent model that has a Calculator" do |parent_name|
       expect(error_messages).not_to include(/^Calculator preferred/)
     end
   end
+
+  context "when number localization is enabled and the associated Calculator is invalid" do
+    let(:localized_parent) do
+      build(parent_name, calculator: Calculator::FlatRate.new(preferred_amount: "invalid"))
+    end
+
+    before do
+      allow(Spree::Config).to receive(:enable_localized_number?).and_return true
+      localized_parent.valid?
+    end
+
+    it "adds custom error messages to base" do
+      expect(localized_parent.errors[:base]).to include(
+        /#{I18n.t('spree.localized_number.invalid_format')}/
+      )
+    end
+  end
 end