A spec knows where a generator was found and how to instantiate it. Metadata include the generator's name, its base path, and the source which yielded it (PathSource, GemSource, etc.)

Methods
C
K
N
Attributes
[R] name
[R] path
[R] source
Class Public methods
new(name, path, source)

Source: show 

# File rails/railties/lib/rails_generator/spec.rb, line 9
def initialize(name, path, source)
  @name, @path, @source = name, path, source
end
Instance Public methods
class_file()

Source: show 

# File rails/railties/lib/rails_generator/spec.rb, line 24
def class_file
  "#{path}/#{name}_generator.rb"
end
class_name()

Source: show 

# File rails/railties/lib/rails_generator/spec.rb, line 28
def class_name
  "#{name.camelize}Generator"
end
klass()

Look up the generator class. Require its class file, find the class in ObjectSpace, tag it with this spec, and return.

Source: show 

# File rails/railties/lib/rails_generator/spec.rb, line 15
def klass
  unless @klass
    require class_file
    @klass = lookup_class
    @klass.spec = self
  end
  @klass
end