makes the census api try several variants before failing a verification

spec/lib/census_api_spec.rb

@@ -0,0 +1,55 @@
+require 'rails_helper'
+
+describe CensusApi do
+  let(:api) { described_class.new }
+
+  describe '#get_document_number_variants' do
+    it "trims and cleans up entry" do
+      expect(api.get_document_number_variants(2, '  1 2@ 34')).to eq(['1234'])
+    end
+
+    it "returns only one try for passports & residence cards" do
+      expect(api.get_document_number_variants(2, '1234')).to eq(['1234'])
+      expect(api.get_document_number_variants(3, '1234')).to eq(['1234'])
+    end
+
+    it 'takes only the last 8 digits for dnis and resicence cards' do
+      expect(api.get_document_number_variants(1, '543212345678')).to eq(['12345678'])
+    end
+
+    it 'tries all the dni variants padding with zeroes' do
+      expect(api.get_document_number_variants(1, '0123456')).to eq(['123456', '0123456', '00123456'])
+      expect(api.get_document_number_variants(1, '00123456')).to eq(['123456', '0123456', '00123456'])
+    end
+
+    it 'adds upper and lowercase letter when the letter is present' do
+      expect(api.get_document_number_variants(1, '1234567A')).to eq(['1234567', '01234567', '1234567a', '1234567A', '01234567a', '01234567A'])
+    end
+  end
+
+  describe '#call' do
+    let(:invalid_body) { {get_habita_datos_response: {get_habita_datos_return: {datos_habitante: {}}}} }
+    let(:valid_body){ {get_habita_datos_response: {get_habita_datos_return: {datos_habitante: {item: {fecha_nacimiento_string: "1/1/1980"}}}}} }
+
+    it "returns the response for the first valid variant" do
+      allow(api).to receive(:get_response_body).with(1, "00123456").and_return(invalid_body)
+      allow(api).to receive(:get_response_body).with(1, "123456").and_return(invalid_body)
+      expect(api).to receive(:get_response_body).with(1, "0123456").and_return(valid_body)
+
+      response = api.call(1, "123456")
+
+      expect(response).to be_valid
+      expect(response.date_of_birth).to eq('1/1/1980')
+    end
+
+    it "returns the last failed response" do
+      expect(api).to receive(:get_response_body).with(1, "00123456").and_return(invalid_body)
+      expect(api).to receive(:get_response_body).with(1, "123456").and_return(invalid_body)
+      expect(api).to receive(:get_response_body).with(1, "0123456").and_return(invalid_body)
+      response = api.call(1, "123456")
+
+      expect(response).to_not be_valid
+    end
+  end
+
+end