Method: MethodSequenceChecker#decorate

Defined in:
lib/pippi/checks/method_sequence_checker.rb

#decorate ⇒ Object 



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# File 'lib/pippi/checks/method_sequence_checker.rb', line 18

def decorate
  clazz_to_decorate.class_exec(check, self) do |my_check, method_sequence_check_instance|
    name = "@_pippi_check_#{my_check.class.name.split('::').last.downcase}"
    self.instance_variable_set(name, my_check)
    self.class.send(:define_method, name[1..-1]) do
      instance_variable_get(name)
    end

    # e.g., "size" in "select followed by size"
    second_method_decorator = if method_sequence_check_instance.second_method_arity_type.kind_of?(Module)
      method_sequence_check_instance.second_method_arity_type
    else
      Module.new do
        define_method(method_sequence_check_instance.method2) do |*args, &blk|
          # Using "self.class" implies that the first method invocation returns the same type as the receiver
          # e.g., Array#select returns an Array.  Would need to further parameterize this to get
          # different behavior.
          self.class.instance_variable_get(name).add_problem
          if method_sequence_check_instance.should_check_subsequent_calls && method_sequence_check_instance.clazz_to_decorate == Array
            problem_location = caller_locations.find { |c| c.to_s !~ /byebug|lib\/pippi\/checks/ }
            self.class.instance_variable_get(name).method_names_that_indicate_this_is_being_used_as_a_collection.each do |this_means_its_ok_sym|
              define_singleton_method(this_means_its_ok_sym, self.class.instance_variable_get(name).clear_fault_proc(self.class.instance_variable_get(name), problem_location))
            end
          end
          if method_sequence_check_instance.second_method_arity_type == ARITY_TYPE_BLOCK_ARG
            super(&blk)
          elsif method_sequence_check_instance.second_method_arity_type == ARITY_TYPE_NONE
            super()
          end
        end
      end
    end

    # e.g., "select" in "select followed by size"
   first_method_decorator = Module.new do
      define_method(method_sequence_check_instance.method1) do |*args, &blk|
        result = if method_sequence_check_instance.first_method_arity_type == ARITY_TYPE_BLOCK_ARG
          super(&blk)
        elsif method_sequence_check_instance.first_method_arity_type == ARITY_TYPE_NONE
          super()
        end
        if self.class.instance_variable_get(name)
          result.extend second_method_decorator
          self.class.instance_variable_get(name).array_mutator_methods.each do |this_means_its_ok_sym|
            result.define_singleton_method(this_means_its_ok_sym, self.class.instance_variable_get(name).its_ok_watcher_proc(second_method_decorator, method_sequence_check_instance.method2))
          end
        end
        result
      end
    end
    prepend first_method_decorator
  end
end