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Diffstat (limited to 'railties/lib/rails/generators/base.rb')
| -rw-r--r-- | railties/lib/rails/generators/base.rb | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/railties/lib/rails/generators/base.rb b/railties/lib/rails/generators/base.rb new file mode 100644 index 0000000000..720caa5b3f --- /dev/null +++ b/railties/lib/rails/generators/base.rb @@ -0,0 +1,349 @@ +require 'thor' +require 'rails/generators/actions' + +module Rails + module Generators + class Error < Thor::Error + end + + class Base < Thor::Group + include Thor::Actions + include Rails::Generators::Actions + + add_runtime_options! + + # Automatically sets the source root based on the class name. + # + def self.source_root + @_rails_source_root ||= File.expand_path(File.join(File.dirname(__FILE__), + base_name, generator_name, 'templates')) + end + + # Tries to get the description from a USAGE file one folder above the source + # root otherwise uses a default description. + # + def self.desc(description=nil) + return super if description + usage = File.expand_path(File.join(source_root, "..", "USAGE")) + + @desc ||= if File.exist?(usage) + File.read(usage) + else + "Description:\n Create #{base_name.humanize.downcase} files for #{generator_name} generator." + end + end + + # Convenience method to get the namespace from the class name. It's the + # same as Thor default except that the Generator at the end of the class + # is removed. + # + def self.namespace(name=nil) + return super if name + @namespace ||= super.sub(/_generator$/, '') + end + + # Invoke a generator based on the value supplied by the user to the + # given option named "name". A class option is created when this method + # is invoked and you can set a hash to customize it. + # + # ==== Examples + # + # module Rails::Generators + # class ControllerGenerator < Base + # hook_for :test_framework, :aliases => "-t" + # end + # end + # + # The example above will create a test framework option and will invoke + # a generator based on the user supplied value. + # + # For example, if the user invoke the controller generator as: + # + # ruby script/generate controller Account --test-framework=test_unit + # + # The controller generator will then try to invoke the following generators: + # + # "rails:generators:test_unit", "test_unit:generators:controller", "test_unit" + # + # In this case, the "test_unit:generators:controller" is available and is + # invoked. This allows any test framework to hook into Rails as long as it + # provides any of the hooks above. + # + # ==== Options + # + # This lookup can be customized with two options: :base and :as. The first + # is the root module value and in the example above defaults to "rails". + # The later defaults to the generator name, without the "Generator" ending. + # + # Let's suppose you are creating a generator that needs to invoke the + # controller generator from test unit. Your first attempt is: + # + # class AwesomeGenerator < Rails::Generators::Base + # hook_for :test_framework + # end + # + # The lookup in this case for test_unit as input is: + # + # "test_unit:generators:awesome", "test_unit" + # + # Which is not the desired the lookup. You can change it by providing the + # :as option: + # + # class AwesomeGenerator < Rails::Generators::Base + # hook_for :test_framework, :as => :controller + # end + # + # And now it will lookup at: + # + # "test_unit:generators:awesome", "test_unit" + # + # Similarly, if you want it to also lookup in the rails namespace, you just + # need to provide the :base value: + # + # class AwesomeGenerator < Rails::Generators::Base + # hook_for :test_framework, :base => :rails, :as => :controller + # end + # + # And the lookup is exactly the same as previously: + # + # "rails:generators:test_unit", "test_unit:generators:controller", "test_unit" + # + # ==== Switches + # + # All hooks come with switches for user interface. If the user don't want + # to use any test framework, he can do: + # + # ruby script/generate controller Account --skip-test-framework + # + # Or similarly: + # + # ruby script/generate controller Account --no-test-framework + # + # ==== Boolean hooks + # + # In some cases, you want to provide a boolean hook. For example, webrat + # developers might want to have webrat available on controller generator. + # This can be achieved as: + # + # Rails::Generators::ControllerGenerator.hook_for :webrat, :type => :boolean + # + # Then, if you want, webrat to be invoked, just supply: + # + # ruby script/generate controller Account --webrat + # + # The hooks lookup is similar as above: + # + # "rails:generators:webrat", "webrat:generators:controller", "webrat" + # + # ==== Custom invocations + # + # You can also supply a block to hook_for to customize how the hook is + # going to be invoked. The block receives two parameters, an instance + # of the current class and the klass to be invoked. + # + # For example, in the resource generator, the controller should be invoked + # with a pluralized class name. By default, it is invoked with the same + # name as the resource generator, which is singular. To change this, we + # can give a block to customize how the controller can be invoked. + # + # hook_for :resource_controller do |instance, controller| + # instance.invoke controller, [ instance.name.pluralize ] + # end + # + def self.hook_for(*names, &block) + options = names.extract_options! + in_base = options.delete(:in) || base_name + as_hook = options.delete(:as) || generator_name + + names.each do |name| + defaults = if options[:type] == :boolean + { } + elsif [true, false].include?(default_value_for_option(name, options)) + { :banner => "" } + else + { :desc => "#{name.to_s.humanize} to be invoked", :banner => "NAME" } + end + + unless class_options.key?(name) + class_option name, defaults.merge!(options) + end + + hooks[name] = [ in_base, as_hook ] + invoke_from_option name, options, &block + end + end + + # Remove a previously added hook. + # + # ==== Examples + # + # remove_hook_for :orm + # + def self.remove_hook_for(*names) + remove_invocation *names + + names.each do |name| + hooks.delete(name) + end + end + + # Make class option aware of Rails::Generators.options and Rails::Generators.aliases. + # + def self.class_option(name, options={}) #:nodoc: + options[:desc] = "Indicates when to generate #{name.to_s.humanize.downcase}" unless options.key?(:desc) + options[:aliases] = default_aliases_for_option(name, options) + options[:default] = default_value_for_option(name, options) + super(name, options) + end + + # Cache source root and add lib/generators/base/generator/templates to + # source paths. + # + def self.inherited(base) #:nodoc: + super + base.source_root # Cache source root + + if defined?(RAILS_ROOT) && base.name !~ /Base$/ + path = File.expand_path(File.join(RAILS_ROOT, 'lib', 'templates')) + if base.name.include?('::') + base.source_paths << File.join(path, base.base_name, base.generator_name) + else + base.source_paths << File.join(path, base.generator_name) + end + end + end + + protected + + # Check whether the given class names are already taken by user + # application or Ruby on Rails. + # + def class_collisions(*class_names) #:nodoc: + return unless behavior == :invoke + + class_names.flatten.each do |class_name| + class_name = class_name.to_s + next if class_name.strip.empty? + + # Split the class from its module nesting + nesting = class_name.split('::') + last_name = nesting.pop + + # Hack to limit const_defined? to non-inherited on 1.9 + extra = [] + extra << false unless Object.method(:const_defined?).arity == 1 + + # Extract the last Module in the nesting + last = nesting.inject(Object) do |last, nest| + break unless last.const_defined?(nest, *extra) + last.const_get(nest) + end + + if last && last.const_defined?(last_name.camelize, *extra) + raise Error, "The name '#{class_name}' is either already used in your application " << + "or reserved by Ruby on Rails. Please choose an alternative and run " << + "this generator again." + end + end + end + + # Use Rails default banner. + # + def self.banner + "#{$0} #{generator_name} #{self.arguments.map{ |a| a.usage }.join(' ')} [options]" + end + + # Sets the base_name taking into account the current class namespace. + # + def self.base_name + @base_name ||= self.name.split('::').first.underscore + end + + # Removes the namespaces and get the generator name. For example, + # Rails::Generators::MetalGenerator will return "metal" as generator name. + # + def self.generator_name + @generator_name ||= begin + klass_name = self.name.split('::').last + klass_name.sub!(/Generator$/, '') + klass_name.underscore + end + end + + # Return the default value for the option name given doing a lookup in + # Rails::Generators.options. + # + def self.default_value_for_option(name, options) + config = Rails::Generators.options + generator, base = generator_name.to_sym, base_name.to_sym + + if config[generator] && config[generator].key?(name) + config[generator][name] + elsif config[base] && config[base].key?(name) + config[base][name] + elsif config[:rails].key?(name) + config[:rails][name] + else + options[:default] + end + end + + # Return default aliases for the option name given doing a lookup in + # Rails::Generators.aliases. + # + def self.default_aliases_for_option(name, options) + config = Rails::Generators.aliases + generator, base = generator_name.to_sym, base_name.to_sym + + if config[generator] && config[generator].key?(name) + config[generator][name] + elsif config[base] && config[base].key?(name) + config[base][name] + elsif config[:rails].key?(name) + config[:rails][name] + else + options[:aliases] + end + end + + # Keep hooks configuration that are used on prepare_for_invocation. + # + def self.hooks #:nodoc: + @hooks ||= from_superclass(:hooks, {}) + end + + # Prepare class invocation to search on Rails namespace if a previous + # added hook is being used. + # + def self.prepare_for_invocation(name, value) #:nodoc: + if value && constants = self.hooks[name] + Rails::Generators.find_by_namespace(value, *constants) + else + super + end + end + + # Small macro to add ruby as an option to the generator with proper + # default value plus an instance helper method called shebang. + # + def self.add_shebang_option! + class_option :ruby, :type => :string, :aliases => "-r", :default => Thor::Util.ruby_command, + :desc => "Path to the Ruby binary of your choice", :banner => "PATH" + + no_tasks { + define_method :shebang do + @shebang ||= begin + command = if options[:ruby] == Thor::Util.ruby_command + "/usr/bin/env #{File.basename(Thor::Util.ruby_command)}" + else + options[:ruby] + end + "#!#{command}" + end + end + } + end + + end + end +end |