require 'thor/group'
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 ||= begin
if base_name && generator_name
File.expand_path(File.join("../../generators", base_name, generator_name, 'templates'), File.dirname(__FILE__))
end
end
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$/, '').sub(/:generators:/, ':')
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:test_unit", "test_unit:controller", "test_unit"
#
# Notice that "rails:generators:test_unit" could be loaded as well, what
# Rails looks for is the first and last parts of the namespace. This is what
# allows any test framework to hook into Rails as long as it provides any
# of the hooks above.
#
# ==== Options
#
# The first and last part used to find the generator to be invoked are
# guessed based on class invokes hook_for, as noticed in the example above.
# This can be customized with two options: :base and :as.
#
# 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: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:controller", "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, :in => :rails, :as => :controller
# end
#
# And the lookup is exactly the same as previously:
#
# "rails:test_unit", "test_unit: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 arguments, 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. But 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
# Cache source root, we need to do this, since __FILE__ is a relative value
# and can point to wrong directions when inside an specified directory.
base.source_root
if base.name && base.name !~ /Base$/
Rails::Generators.subclasses << base
if defined?(Rails.root) && Rails.root
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
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
"#{$0} #{generator_name} #{self.arguments.map{ |a| a.usage }.join(' ')} [options]"
end
# Sets the base_name taking into account the current class namespace.
#
def self.base_name
@base_name ||= begin
if base = name.to_s.split('::').first
base.underscore
end
end
end
# Removes the namespaces and get the generator name. For example,
# Rails::Generators::MetalGenerator will return "metal" as generator name.
#
def self.generator_name
@generator_name ||= begin
if generator = name.to_s.split('::').last
generator.sub!(/Generator$/, '')
generator.underscore
end
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)
default_for_option(Rails::Generators.options, name, options, options[:default])
end
# Return default aliases for the option name given doing a lookup in
# Rails::Generators.aliases.
#
def self.default_aliases_for_option(name, options)
default_for_option(Rails::Generators.aliases, name, options, options[:aliases])
end
# Return default for the option name given doing a lookup in config.
#
def self.default_for_option(config, name, options, default)
if generator_name and c = config[generator_name.to_sym] and c.key?(name)
c[name]
elsif base_name and c = config[base_name.to_sym] and c.key?(name)
c[name]
elsif config[:rails].key?(name)
config[:rails][name]
else
default
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:
return super unless value.is_a?(String) || value.is_a?(Symbol)
if value && constants = self.hooks[name]
value = name if TrueClass === value
Rails::Generators.find_by_namespace(value, *constants)
elsif klass = Rails::Generators.find_by_namespace(value)
klass
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