Module: Rails::Decorators::Decorator

Defined in:
lib/rails/decorators/decorator.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.decorate(*targets, &module_definition) ⇒ Object 



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# File 'lib/rails/decorators/decorator.rb', line 14

def self.decorate(*targets, &module_definition)
  options = targets.extract_options!

  targets.each do |target|
    unless target.is_a?(Class)
      raise(
        InvalidDecorator,
        "\n          Problem:\n            You cannot decorate a Module\n          Summary:\n            Decoration only works with classes. Decorating modules requires\n            managing load order, a problem that is very complicated and\n            beyond the scope of this system.\n          Resolution:\n            Decorate multiple classes that include the module like so:\n            `decorate Catalog::Product, Content::Page do`\n        eos\n      )\n    end\n\n    if target.name.to_s.end_with?('Helper')\n      raise(\n        InvalidDecorator,\n        <<-eos.strip_heredoc\n\n          Problem:\n            Rails::Decorators doesn't work with helpers.\n          Summary:\n            Rails does some magic with helpers which in certain cases\n            causes decoration to not work.\n          Resolution:\n            Create a new helper and in a `to_prepare` block, use\n            ActionPack's `helper` method to include the helper, e.g.\n            `MyEngine::ApplicationController.helper(MyEngine::BlogsHelper)`\n        eos\n      )\n    end\n\n    decorator_name = \"\#{options[:with].to_s.camelize}\#{target.to_s.demodulize}Decorator\"\n\n    if target.const_defined?(decorator_name)\n      # We are probably reloading in Rails development env if this happens\n      next if !Rails.application.config.cache_classes\n\n      raise(\n        InvalidDecorator,\n        <<-eos.strip_heredoc\n\n          Problem:\n            \#{decorator_name} is already defined in \#{target.name}.\n          Summary:\n            When decorating a class, Rails::Decorators dynamically defines\n            a module for prepending the decorations passed in the block. In\n            this case, the name for the decoration module is already defined\n            in the namespace, so decorating would redefine the constant.\n          Resolution:\n            Please specify a unique `with` option when decorating \#{target.name}.\n        eos\n      )\n    end\n\n    mod = Module.new do\n      extend Rails::Decorators::Decorator\n      module_eval(&module_definition)\n    end\n\n    target.const_set(decorator_name, mod)\n    mod.decorates(target)\n  end\nend\n".strip_heredoc

.loader(roots) ⇒ Object 



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# File 'lib/rails/decorators/decorator.rb', line 4

def self.loader(roots)
  Proc.new do
    roots.each do |root|
      decorators = Dir.glob("#{root}/app/**/*.#{Rails::Decorators.extension}")
      decorators.sort!
      decorators.each { |d| require_dependency(d) }
    end
  end
end

Instance Method Details

#class_methods(&class_methods_module_definition) ⇒ Object Also known as: module_methods 



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# File 'lib/rails/decorators/decorator.rb', line 105

def class_methods(&class_methods_module_definition)
  mod = const_set(:ClassMethodsDecorator, Module.new)
  mod.module_eval(&class_methods_module_definition)
end

#decorated(&block) ⇒ Object 



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# File 'lib/rails/decorators/decorator.rb', line 101

def decorated(&block)
  instance_variable_set(:@_decorated_block, block)
end

#decorates(klass) ⇒ Object 



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# File 'lib/rails/decorators/decorator.rb', line 111

def decorates(klass)
  klass.send(:prepend, self)
end

#prepend_features(base) ⇒ Object 



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# File 'lib/rails/decorators/decorator.rb', line 87

def prepend_features(base)
  super

  if const_defined?(:ClassMethodsDecorator)
    base
      .singleton_class
      .send(:prepend, const_get(:ClassMethodsDecorator))
  end

  if instance_variable_defined?(:@_decorated_block)
    base.class_eval(&@_decorated_block)
  end
end