Add Lazy loading config (#3244)

* feat(lazy-loading): add `Faker::Config.lazy_loading?` (#3226)

Adds configuration option to enable/disable lazy loading
so it can be explicitly enabled during beta testing.

* Introduce lazy loading as an optional config (#3228)

* Lazy load generators

To keep this change backwards compatible, we introduce
lazy loading as a config option.

We need to load main classes
first for nested generators such as 'music' and
when lazy loading is not enabled. 'internet/http'.

This will avoid the need for renaming these generators.

Co-authored-by: Thiago Araujo <thd.araujo@gmail.com>

* Clean up skipped generators from determinism test

* Rename test file following conventions

* Run lazy loading smoke test in CI

* Check for true values when setting ENV['FAKER_LAZY_LOAD']

Covers the case of users setting the env using
truthy values.

* Better code for checking for ENV values

---------

Co-authored-by: Thiago Araujo <thd.araujo@gmail.com>

---------

Co-authored-by: Thiago Araujo <707418+thdaraujo@users.noreply.github.com>
Co-authored-by: Thiago Araujo <thd.araujo@gmail.com>

Author: stefannibrasil

.github/workflows/ruby.yml

@@ -9,9 +9,13 @@ name: Tests
 
 on:
   push:
-    branches: [ main ]
+    branches:
+      - main
+      - 'lazy-loading-beta'
   pull_request:
-    branches: [ main ]
+    branches:
+      - main
+      - 'lazy-loading-beta'
   workflow_dispatch:
 
 permissions:
@@ -58,3 +62,18 @@ jobs:
 
     - name: Run tests
       run: bundle exec rake test
+  test-with-lazy-loading:
+    name: Ruby 3.2 with lazy loading
+    runs-on: ubuntu-latest
+    env:
+      BUNDLE_WITHOUT: benchmark
+    steps:
+    - uses: actions/checkout@v6
+    - uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: '3.2'
+        bundler-cache: true
+
+    - name: Run tests with lazy load enabled
+      run: FAKER_LAZY_LOAD=1 bundle exec rake test
+

lib/faker.rb

@@ -38,6 +38,18 @@ def random=(new_random)
       def random
         Thread.current[:faker_config_random] || Random
       end
+
+      def lazy_loading?
+        if ENV.key?('FAKER_LAZY_LOAD') && !ENV['FAKER_LAZY_LOAD'].nil?
+          %w[true TRUE 1].include?(ENV.fetch('FAKER_LAZY_LOAD', nil))
+        else
+          Thread.current[:faker_lazy_loading] == true
+        end
+      end
+
+      def lazy_loading=(value)
+        Thread.current[:faker_lazy_loading] = value
+      end
     end
   end
 
@@ -275,7 +287,47 @@ def disable_enforce_available_locales
       end
     end
   end
+
+  if Faker::Config.lazy_loading?
+    def self.load_path(*constants)
+      constants.map do |class_name|
+        class_name
+          .to_s
+          .gsub('::', '/')
+          .gsub(/([A-Z]+)([A-Z][a-z])/, '\1_\2')
+          .gsub(/([a-z\d])([A-Z])/, '\1_\2')
+          .tr('-', '_')
+          .downcase
+      end.join('/')
+    end
+
+    def self.lazy_load(klass)
+      def klass.const_missing(class_name)
+        load_path = case class_name
+                    when :DnD
+                      Faker.load_path('faker/games/dnd')
+                    else
+                      Faker.load_path(name, class_name)
+                    end
+
+        begin
+          require(load_path)
+        rescue LoadError
+          require(load_path.gsub('faker/', 'faker/default/'))
+        end
+
+        const_get(class_name)
+      end
+    end
+
+    lazy_load(self)
+  end
 end
 
-# require faker objects
-Dir.glob(File.join(mydir, 'faker', '/**/*.rb')).each { |file| require file }
+unless Faker::Config.lazy_loading?
+  rb_files = []
+  rb_files << File.join(mydir, 'faker', '*.rb')
+  rb_files << File.join(mydir, 'faker', '/**/*.rb')
+
+  Dir.glob(rb_files).each { |file| require file }
+end

lib/faker/blockchain.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Faker
+  class Blockchain
+    if Faker::Config.lazy_loading?
+      Faker.lazy_load(self)
+    end
+  end
+end

lib/faker/books.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Faker
+  class Books
+    if Faker::Config.lazy_loading?
+      Faker.lazy_load(self)
+    end
+  end
+end

lib/faker/creature.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Faker
+  class Creature
+    if Faker::Config.lazy_loading?
+      Faker.lazy_load(self)
+    end
+  end
+end

lib/faker/default.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Faker
+  class Default
+    if Faker::Config.lazy_loading?
+      Faker.lazy_load(self)
+    end
+  end
+end

lib/faker/books/book.rb lib/faker/default/book.rblib/faker/books/book.rb renamed to lib/faker/default/book.rb

@@ -14,7 +14,7 @@ class << self
       # @faker.version 3.2.1
       def heading
         level = rand(1..6)
-        "<h#{level}>#{Lorem.word.capitalize}</h#{level}>"
+        "<h#{level}>#{Faker::Lorem.word.capitalize}</h#{level}>"
       end
 
       ##
@@ -97,7 +97,7 @@ def unordered_list
       #
       # @faker.version 3.2.1
       def code
-        "<code>#{Lorem.sentence(word_count: 1)}</code>"
+        "<code>#{Faker::Lorem.sentence(word_count: 1)}</code>"
       end
 
       ##
@@ -165,7 +165,7 @@ def link(rel: 'stylesheet')
       #   Faker::HTML.element(tag: 'div', content: "This is a div with XSS attributes.", attributes: {class: 'xss', onclick: "alert('XSS')"}) #=> "<div class=\"xss\" onclick=\"alert('XSS')\">This is a div with XSS attributes.</div>"
       #
       # @faker.version 3.2.1
-      def element(tag: 'div', content: Lorem.sentence(word_count: 3), attributes: { class: Lorem.word, onclick: "#{Lorem.word}()" })
+      def element(tag: 'div', content: Faker::Lorem.sentence(word_count: 3), attributes: { class: Faker::Lorem.word, onclick: "#{Faker::Lorem.word}()" })
         attribute_string = attributes.map { |key, value| "#{key}=\"#{value}\"" }.join(' ')
         "<#{tag} #{attribute_string}>#{content}</#{tag}>"
       end

lib/faker/games/game.rb lib/faker/default/game.rblib/faker/games/game.rb renamed to lib/faker/default/game.rb

@@ -58,7 +58,7 @@ def words(number: 3, supplemental: false, exclude_words: nil)
       #
       # @faker.version 2.1.3
       def character
-        sample(Types::CHARACTERS)
+        sample(Faker::Types::CHARACTERS)
       end
 
       ##
@@ -78,7 +78,7 @@ def character
       #
       # @faker.version 2.1.3
       def characters(number: 255, min_alpha: 0, min_numeric: 0)
-        Alphanumeric.alphanumeric(number: number, min_alpha: min_alpha, min_numeric: min_numeric)
+        Faker::Alphanumeric.alphanumeric(number: number, min_alpha: min_alpha, min_numeric: min_numeric)
       end
 
       ##