Implement pluralization engine

app/models/rosetta/locale.rb

@@ -10,6 +10,7 @@ class Locale < ApplicationRecord
 
     has_many :text_entries, dependent: :destroy
     after_create_commit :notify_translated_models
+    has_many :pluralization_rules, dependent: :destroy
 
     class << self
       def available_locales

app/models/rosetta/pluralization_rule.rb

@@ -0,0 +1,21 @@
+module Rosetta
+  class PluralizationRule < ApplicationRecord
+    OPERATORS = {
+      less_than_or_equal_to: Pluralization::Operators::LessThanOrEqualTo,
+      less_than: Pluralization::Operators::LessThan,
+      equal_to: Pluralization::Operators::EqualTo,
+      greater_than_or_equal_to: Pluralization::Operators::GreaterThanOrEqualTo,
+      greater_than: Pluralization::Operators::GreaterThan
+    }.with_indifferent_access
+
+    belongs_to :locale
+
+    validates :name, :operator, :threshold, presence: true
+    validates :threshold, numericality: { greater_than_or_equal_to: 0 }
+    validates :operator, inclusion: { in: OPERATORS.keys }
+
+    def activated?(test_value)
+      OPERATORS[operator].new(value: test_value, threshold: threshold).check
+    end
+  end
+end

db/migrate/20240920134441_create_rosetta_pluralization_rules.rb

@@ -0,0 +1,14 @@
+class CreateRosettaPluralizationRules < ActiveRecord::Migration[6.1]
+  def change
+    create_table :rosetta_pluralization_rules do |t|
+      t.string :name
+      t.string :operator
+      t.integer :threshold
+      t.references :locale, null: false
+
+      t.timestamps
+
+      t.foreign_key :rosetta_locales, column: :locale_id
+    end
+  end
+end

db/migrate/20240923100651_add_default_to_rosetta_locales.rb

@@ -1,4 +1,4 @@
-class AddDefaultToRosettaLocales < ActiveRecord::Migration[7.2]
+class AddDefaultToRosettaLocales < ActiveRecord::Migration[6.1]
   def change
     add_column :rosetta_locales, :default, :boolean, default: false
   end

lib/rosetta-rails.rb

@@ -9,6 +9,13 @@
 require "rosetta/translated/create"
 require "rosetta/translated/delete"
 
+require "rosetta/pluralization/base_operator"
+require "rosetta/pluralization/operators/less_than_or_equal_to"
+require "rosetta/pluralization/operators/less_than"
+require "rosetta/pluralization/operators/equal_to"
+require "rosetta/pluralization/operators/greater_than_or_equal_to"
+require "rosetta/pluralization/operators/greater_than"
+
 module Rosetta
   module Base
     def locale

lib/rosetta/pluralization/base_operator.rb

@@ -0,0 +1,14 @@
+module Rosetta
+  module Pluralization
+    class BaseOperator
+      def initialize(value:, threshold:)
+        @value = value
+        @threshold = threshold
+      end
+
+      def check
+        raise NotImplementedError
+      end
+    end
+  end
+end

lib/rosetta/pluralization/operators/equal_to.rb

@@ -0,0 +1,11 @@
+module Rosetta
+  module Pluralization
+    module Operators
+      class EqualTo < BaseOperator
+        def check
+          @value == @threshold
+        end
+      end
+    end
+  end
+end

lib/rosetta/pluralization/operators/greater_than.rb

@@ -0,0 +1,11 @@
+module Rosetta
+  module Pluralization
+    module Operators
+      class GreaterThan < BaseOperator
+        def check
+          @value > @threshold
+        end
+      end
+    end
+  end
+end

lib/rosetta/pluralization/operators/greater_than_or_equal_to.rb

@@ -0,0 +1,11 @@
+module Rosetta
+  module Pluralization
+    module Operators
+      class GreaterThanOrEqualTo < BaseOperator
+        def check
+          @value >= @threshold
+        end
+      end
+    end
+  end
+end

lib/rosetta/pluralization/operators/less_than.rb

@@ -0,0 +1,11 @@
+module Rosetta
+  module Pluralization
+    module Operators
+      class LessThan < BaseOperator
+        def check
+          @value < @threshold
+        end
+      end
+    end
+  end
+end

lib/rosetta/pluralization/operators/less_than_or_equal_to.rb

@@ -0,0 +1,11 @@
+module Rosetta
+  module Pluralization
+    module Operators
+      class LessThanOrEqualTo < BaseOperator
+        def check
+          @value <= @threshold
+        end
+      end
+    end
+  end
+end

test/dummy/db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2024_10_02_152043) do
+ActiveRecord::Schema[7.2].define(version: 2024_10_02_152043) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -24,6 +24,16 @@
     t.index ["code"], name: "index_rosetta_locales_on_code", unique: true
   end
 
+  create_table "rosetta_pluralization_rules", force: :cascade do |t|
+    t.string "name"
+    t.string "operator"
+    t.integer "threshold"
+    t.bigint "locale_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["locale_id"], name: "index_rosetta_pluralization_rules_on_locale_id"
+  end
+
   create_table "rosetta_text_entries", force: :cascade do |t|
     t.text "content", null: false
     t.bigint "locale_id", null: false
@@ -46,6 +56,7 @@
     t.index ["to_id"], name: "index_rosetta_translations_on_to_id"
   end
 
+  add_foreign_key "rosetta_pluralization_rules", "rosetta_locales", column: "locale_id"
   add_foreign_key "rosetta_text_entries", "rosetta_locales", column: "locale_id"
   add_foreign_key "rosetta_translations", "rosetta_locales", column: "target_locale_id"
   add_foreign_key "rosetta_translations", "rosetta_text_entries", column: "from_id"

test/fixtures/rosetta/pluralization_rules.yml

@@ -0,0 +1,7 @@
+# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+french_less_than_or_equal_to_one:
+  name: Less than or equal to one
+  operator: less_than_or_equal_to
+  threshold: 1
+  locale: french

test/helpers/pluralization_operator_helpers.rb

@@ -0,0 +1,5 @@
+module PluralizationOperatorHelpers
+  def operator_class
+    self.class.name.gsub(/Test\z/, "").constantize
+  end
+end

test/lib/rosetta/pluralization/operators/equal_to_test.rb

@@ -0,0 +1,11 @@
+require "test_helper"
+
+class Rosetta::Pluralization::Operators::EqualToTest < ActiveSupport::TestCase
+  include PluralizationOperatorHelpers
+
+  test "checks correct counts" do
+    assert operator_class.new(value: 1, threshold: 1).check
+    assert_not operator_class.new(value: 2, threshold: 1).check
+    assert_not operator_class.new(value: 0, threshold: 1).check
+  end
+end

test/lib/rosetta/pluralization/operators/greater_than_or_equal_to.rb

@@ -0,0 +1,11 @@
+require "test_helper"
+
+class Rosetta::Pluralization::Operators::GreaterThanOrEqualToTest < ActiveSupport::TestCase
+  include PluralizationOperatorHelpers
+
+  test "checks correct counts" do
+    assert operator_class.new(value: 1, threshold: 1).check
+    assert operator_class.new(value: 2, threshold: 1).check
+    assert_not operator_class.new(value: 0, threshold: 1).check
+  end
+end

test/lib/rosetta/pluralization/operators/greater_than_test.rb

@@ -0,0 +1,11 @@
+require "test_helper"
+
+class Rosetta::Pluralization::Operators::GreaterThanTest < ActiveSupport::TestCase
+  include PluralizationOperatorHelpers
+
+  test "checks correct counts" do
+    assert operator_class.new(value: 2, threshold: 1).check
+    assert_not operator_class.new(value: 1, threshold: 1).check
+      assert_not operator_class.new(value: 0, threshold: 1).check
+  end
+end

test/lib/rosetta/pluralization/operators/less_than_or_equal_to_test.rb

@@ -0,0 +1,11 @@
+require "test_helper"
+
+class Rosetta::Pluralization::Operators::LessThanOrEqualToTest < ActiveSupport::TestCase
+  include PluralizationOperatorHelpers
+
+  test "checks correct counts" do
+    assert operator_class.new(value: 2, threshold: 2).check
+    assert operator_class.new(value: 1, threshold: 2).check
+    assert_not operator_class.new(value: 5, threshold: 2).check
+  end
+end

test/lib/rosetta/pluralization/operators/less_than_test.rb

@@ -0,0 +1,11 @@
+require "test_helper"
+
+class Rosetta::Pluralization::Operators::LessThanTest < ActiveSupport::TestCase
+  include PluralizationOperatorHelpers
+
+  test "checks correct counts" do
+    assert operator_class.new(value: 1, threshold: 2).check
+    assert_not operator_class.new(value: 2, threshold: 2).check
+    assert_not operator_class.new(value: 5, threshold: 2).check
+  end
+end

test/models/rosetta/pluralization_rule_test.rb

@@ -0,0 +1,39 @@
+require "test_helper"
+
+module Rosetta
+  class PluralizationRuleTest < ActiveSupport::TestCase
+    setup do
+      @rule = rosetta_pluralization_rules(:french_less_than_or_equal_to_one)
+    end
+
+    test "valid" do
+      assert @rule.valid?
+    end
+
+    %i[name operator threshold].each do |attribute|
+      test "invalid without #{attribute}" do
+        @rule.public_send("#{attribute}=", nil)
+        assert_not @rule.valid?
+        assert_includes @rule.errors[attribute], "can't be blank"
+      end
+    end
+
+    test "operator must be included in the list" do
+      @rule.operator = "unknown_operator"
+      assert_not @rule.valid?
+      assert_includes @rule.errors[:operator], "is not included in the list"
+    end
+
+    test "value must be positive" do
+      @rule.threshold = -1
+      assert_not @rule.valid?
+      assert_includes @rule.errors[:threshold], "must be greater than or equal to 0"
+    end
+
+    test "#activated?" do
+      assert @rule.activated?(0)
+      assert @rule.activated?(1)
+      assert_not @rule.activated?(2)
+    end
+  end
+end

test/test_helper.rb

@@ -6,6 +6,8 @@
 ActiveRecord::Migrator.migrations_paths << File.expand_path("../db/migrate", __dir__)
 require "rails/test_help"
 
+require_relative "./helpers/pluralization_operator_helpers"
+
 # Load fixtures from the engine
 if ActiveSupport::TestCase.respond_to?(:fixture_paths=)
   ActiveSupport::TestCase.fixture_paths = [ File.expand_path("fixtures", __dir__) ]