Split ComparisonHelper into FieldComparison classes for each fields

CHANGELOG.md

@@ -29,6 +29,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 - Address TestCase#fixture_path deprecation [#94](https://github.com/Shopify/atlas_engine/pull/94)
 - Address parser test cleanup [#92](https://github.com/Shopify/atlas_engine/pull/92)
+- Split field comparison logic into their respective classes [#93](https://github.com/Shopify/atlas_engine/pull/93)
 - Improved validation suggestions for Luxembourg [#82](https://github.com/Shopify/atlas_engine/pull/82)
 - Store a duplicate of Result in ConcernRecord [#85](https://github.com/Shopify/atlas_engine/pull/85)
 - Introduce parser and city exclusion for South Korea [#79](https://github.com/Shopify/atlas_engine/pull/79)

app/countries/atlas_engine/pt/address_validation/validators/full_address/exclusions/zip.rb

@@ -22,7 +22,8 @@ def apply?(session, candidate, address_comparison)
                     address_comparison.building_comparison.nil? ||
                     address_comparison.building_comparison.candidate_ranges.empty?
 
-                  !address_comparison.street_comparison.match? || !address_comparison.building_comparison.match?
+                  !T.must(address_comparison.street_comparison).match? ||
+                    !T.must(address_comparison.building_comparison).match?
                 end
               end
             end

app/models/atlas_engine/address_validation/validators/full_address/address_comparison.rb

@@ -9,18 +9,17 @@ class AddressComparison
           extend T::Sig
           include Comparable
 
-          attr_reader :comparison_helper
-
-          delegate :street_comparison,
-            :city_comparison,
-            :province_code_comparison,
-            :zip_comparison,
-            :building_comparison,
-            to: :comparison_helper
-
           sig { params(address: AbstractAddress, candidate: Candidate, datastore: DatastoreBase).void }
           def initialize(address:, candidate:, datastore:)
-            @comparison_helper = ComparisonHelper.new(address:, candidate:, datastore:)
+            @street_comparison = StreetComparison.new(address: address, candidate: candidate, datastore: datastore)
+            @city_comparison = CityComparison.new(address: address, candidate: candidate, datastore: datastore)
+            @province_code_comparison = ProvinceCodeComparison.new(
+              address: address,
+              candidate: candidate,
+              datastore: datastore,
+            )
+            @zip_comparison = ZipComparison.new(address: address, candidate: candidate, datastore: datastore)
+            @building_comparison = BuildingComparison.new(address: address, candidate: candidate, datastore: datastore)
           end
 
           sig { params(other: AddressComparison).returns(Integer) }
@@ -45,6 +44,31 @@ def potential_match?
             street_comparison.nil? || T.must(street_comparison).potential_match?
           end
 
+          sig { returns(T.nilable(Token::Sequence::Comparison)) }
+          def zip_comparison
+            @zip_comparison.compare
+          end
+
+          sig { returns(T.nilable(Token::Sequence::Comparison)) }
+          def street_comparison
+            @street_comparison.compare
+          end
+
+          sig { returns(T.nilable(Token::Sequence::Comparison)) }
+          def city_comparison
+            @city_comparison.compare
+          end
+
+          sig { returns(T.nilable(Token::Sequence::Comparison)) }
+          def province_code_comparison
+            @province_code_comparison.compare
+          end
+
+          sig { returns(NumberComparison) }
+          def building_comparison
+            @building_comparison.compare
+          end
+
           protected
 
           sig do

app/models/atlas_engine/address_validation/validators/full_address/building_comparison.rb

@@ -0,0 +1,33 @@
+# typed: true
+# frozen_string_literal: true
+
+module AtlasEngine
+  module AddressValidation
+    module Validators
+      module FullAddress
+        class BuildingComparison < FieldComparisonBase
+          extend T::Sig
+
+          sig { override.returns(T.nilable(NumberComparison)) }
+          def compare
+            @building_comparison ||= NumberComparison.new(
+              numbers: datastore.parsings.potential_building_numbers,
+              candidate_ranges: building_ranges_from_candidate(candidate),
+            )
+          end
+
+          private
+
+          sig { params(candidate: Candidate).returns(T::Array[AddressNumberRange]) }
+          def building_ranges_from_candidate(candidate)
+            building_and_unit_ranges = candidate.component(:building_and_unit_ranges)&.value
+            return [] if building_and_unit_ranges.blank?
+
+            building_ranges = JSON.parse(building_and_unit_ranges).keys
+            building_ranges.map { |building_range| AddressNumberRange.new(range_string: building_range) }
+          end
+        end
+      end
+    end
+  end
+end

app/models/atlas_engine/address_validation/validators/full_address/city_comparison.rb

@@ -0,0 +1,25 @@
+# typed: true
+# frozen_string_literal: true
+
+module AtlasEngine
+  module AddressValidation
+    module Validators
+      module FullAddress
+        class CityComparison < FieldComparisonBase
+          extend T::Sig
+
+          sig { override.returns(T.nilable(Token::Sequence::Comparison)) }
+          def compare
+            return @city_comparison if defined?(@city_comparison)
+
+            @city_comparison = best_comparison(
+              datastore.fetch_city_sequence,
+              T.must(candidate.component(:city)).sequences,
+              field_policy(:city),
+            )
+          end
+        end
+      end
+    end
+  end
+end

app/models/atlas_engine/address_validation/validators/full_address/field_comparison_base.rb

@@ -0,0 +1,68 @@
+# typed: true
+# frozen_string_literal: true
+
+module AtlasEngine
+  module AddressValidation
+    module Validators
+      module FullAddress
+        class FieldComparisonBase
+          extend T::Sig
+          extend T::Helpers
+
+          abstract!
+
+          sig { params(address: AbstractAddress, candidate: Candidate, datastore: DatastoreBase).void }
+          def initialize(address:, candidate:, datastore:)
+            @address = address
+            @datastore = datastore
+            @candidate = candidate
+          end
+
+          sig { abstract.returns(T.any(T.nilable(Token::Sequence::Comparison), T.nilable(NumberComparison))) }
+          def compare; end
+
+          private
+
+          sig { returns(AbstractAddress) }
+          attr_reader :address
+
+          sig { returns(DatastoreBase) }
+          attr_reader :datastore
+
+          sig { returns(Candidate) }
+          attr_reader :candidate
+
+          sig do
+            params(
+              sequence: Token::Sequence,
+              component_sequences: T::Array[Token::Sequence],
+              comparison_policy: Token::Sequence::ComparisonPolicy,
+            ).returns(T.nilable(Token::Sequence::Comparison))
+          end
+          def best_comparison(
+            sequence,
+            component_sequences,
+            comparison_policy = Token::Sequence::ComparisonPolicy::DEFAULT_POLICY
+          )
+            component_sequences.map do |component_sequence|
+              Token::Sequence::Comparator.new(
+                left_sequence: sequence,
+                right_sequence: component_sequence,
+                comparison_policy:,
+              ).compare
+            end.min_by.with_index do |comparison, index|
+              # ruby's `min` and `sort` methods are not stable
+              # so we need to prefer the leftmost comparison when two comparisons are equivalent
+              [comparison, index]
+            end
+          end
+
+          sig { params(field: Symbol).returns(Token::Sequence::ComparisonPolicy) }
+          def field_policy(field)
+            datastore.country_profile.validation.comparison_policy(field)
+          end
+        end
+      end
+    end
+  end
+end

app/models/atlas_engine/address_validation/validators/full_address/province_code_comparison.rb

@@ -0,0 +1,34 @@
+# typed: true
+# frozen_string_literal: true
+
+module AtlasEngine
+  module AddressValidation
+    module Validators
+      module FullAddress
+        class ProvinceCodeComparison < FieldComparisonBase
+          extend T::Sig
+
+          sig { override.returns(T.nilable(Token::Sequence::Comparison)) }
+          def compare
+            return @province_code_comparison if defined?(@province_code_comparison)
+
+            normalized_session_province_code = ValidationTranscriber::ProvinceCodeNormalizer.normalize(
+              country_code: address.country_code,
+              province_code: address.province_code,
+            )
+            normalized_candidate_province_code = ValidationTranscriber::ProvinceCodeNormalizer.normalize(
+              country_code: T.must(candidate.component(:country_code)).value,
+              province_code: T.must(candidate.component(:province_code)).value,
+            )
+
+            @province_code_comparison = best_comparison(
+              Token::Sequence.from_string(normalized_session_province_code),
+              [Token::Sequence.from_string(normalized_candidate_province_code)],
+              field_policy(:province_code),
+            )
+          end
+        end
+      end
+    end
+  end
+end