diff --git a/lib/puppet/interface/action.rb b/lib/puppet/interface/action.rb index 08bc0a345..f8eef69b1 100644 --- a/lib/puppet/interface/action.rb +++ b/lib/puppet/interface/action.rb @@ -1,252 +1,257 @@ # -*- coding: utf-8 -*- require 'puppet/interface' require 'puppet/interface/option' class Puppet::Interface::Action def initialize(face, name, attrs = {}) raise "#{name.inspect} is an invalid action name" unless name.to_s =~ /^[a-z]\w*$/ @face = face @name = name.to_sym attrs.each do |k, v| send("#{k}=", v) end @options = {} @when_rendering = {} end # This is not nice, but it is the easiest way to make us behave like the # Ruby Method object rather than UnboundMethod. Duplication is vaguely # annoying, but at least we are a shallow clone. --daniel 2011-04-12 def __dup_and_rebind_to(to) bound_version = self.dup bound_version.instance_variable_set(:@face, to) return bound_version end def to_s() "#{@face}##{@name}" end attr_reader :name attr_accessor :default def default? !!@default end attr_accessor :summary ######################################################################## # Support for rendering formats and all. def when_rendering(type) unless type.is_a? Symbol raise ArgumentError, "The rendering format must be a symbol, not #{type.class.name}" end return unless @when_rendering.has_key? type return @when_rendering[type].bind(@face) end def set_rendering_method_for(type, proc) unless proc.is_a? Proc msg = "The second argument to set_rendering_method_for must be a Proc" msg += ", not #{proc.class.name}" unless proc.nil? raise ArgumentError, msg end if proc.arity != 1 then msg = "when_rendering methods take one argument, the result, not " if proc.arity < 0 then msg += "a variable number" else msg += proc.arity.to_s end raise ArgumentError, msg end unless type.is_a? Symbol raise ArgumentError, "The rendering format must be a symbol, not #{type.class.name}" end if @when_rendering.has_key? type then raise ArgumentError, "You can't define a rendering method for #{type} twice" end # Now, the ugly bit. We add the method to our interface object, and # retrieve it, to rotate through the dance of getting a suitable method # object out of the whole process. --daniel 2011-04-18 @when_rendering[type] = @face.__send__( :__add_method, __render_method_name_for(type), proc) end def __render_method_name_for(type) :"#{name}_when_rendering_#{type}" end private :__render_method_name_for attr_accessor :render_as def render_as=(value) @render_as = value.to_sym end ######################################################################## # Documentation stuff, whee! attr_accessor :summary, :description def summary=(value) value = value.to_s value =~ /\n/ and raise ArgumentError, "Face summary should be a single line; put the long text in 'description' instead." @summary = value end ######################################################################## # Initially, this was defined to allow the @action.invoke pattern, which is # a very natural way to invoke behaviour given our introspection # capabilities. Heck, our initial plan was to have the faces delegate to # the action object for invocation and all. # # It turns out that we have a binding problem to solve: @face was bound to # the parent class, not the subclass instance, and we don't pass the # appropriate context or change the binding enough to make this work. # # We could hack around it, by either mandating that you pass the context in # to invoke, or try to get the binding right, but that has probably got # subtleties that we don't instantly think of – especially around threads. # # So, we are pulling this method for now, and will return it to life when we # have the time to resolve the problem. For now, you should replace... # # @action = @face.get_action(name) # @action.invoke(arg1, arg2, arg3) # # ...with... # # @action = @face.get_action(name) # @face.send(@action.name, arg1, arg2, arg3) # # I understand that is somewhat cumbersome, but it functions as desired. # --daniel 2011-03-31 # # PS: This code is left present, but commented, to support this chunk of # documentation, for the benefit of the reader. # # def invoke(*args, &block) # @face.send(name, *args, &block) # end # We need to build an instance method as a wrapper, using normal code, to be # able to expose argument defaulting between the caller and definer in the # Ruby API. An extra method is, sadly, required for Ruby 1.8 to work since # it doesn't expose bind on a block. # # Hopefully we can improve this when we finally shuffle off the last of Ruby # 1.8 support, but that looks to be a few "enterprise" release eras away, so # we are pretty stuck with this for now. # # Patches to make this work more nicely with Ruby 1.9 using runtime version # checking and all are welcome, provided that they don't change anything # outside this little ol' bit of code and all. # # Incidentally, we though about vendoring evil-ruby and actually adjusting # the internal C structure implementation details under the hood to make # this stuff work, because it would have been cleaner. Which gives you an # idea how motivated we were to make this cleaner. Sorry. # --daniel 2011-03-31 def when_invoked=(block) internal_name = "#{@name} implementation, required on Ruby 1.8".to_sym arity = block.arity if arity == 0 then # This will never fire on 1.8.7, which treats no arguments as "*args", # but will on 1.9.2, which treats it as "no arguments". Which bites, # because this just begs for us to wind up in the horrible situation # where a 1.8 vs 1.9 error bites our end users. --daniel 2011-04-19 raise ArgumentError, "action when_invoked requires at least one argument (options)" elsif arity > 0 then range = Range.new(1, arity - 1) decl = range.map { |x| "arg#{x}" } << "options = {}" optn = "" args = "[" + (range.map { |x| "arg#{x}" } << "options").join(", ") + "]" else range = Range.new(1, arity.abs - 1) decl = range.map { |x| "arg#{x}" } << "*rest" optn = "rest << {} unless rest.last.is_a?(Hash)" if arity == -1 then args = "rest" else args = "[" + range.map { |x| "arg#{x}" }.join(", ") + "] + rest" end end file = __FILE__ + "+eval[wrapper]" line = __LINE__ + 2 # <== points to the same line as 'def' in the wrapper. wrapper = <