Coding exercise

widget_inject.rb

class String

  module WidgetExceptions
    class InvalidWidget < ArgumentError; end
  end
  
  def widget_inject(widgets = [])
    self_with_widgets = self.clone
    widgets.sort_by {|w| w[:position] }.reverse.each do |widget|
      raise WidgetExceptions::InvalidWidget, "widget must be a hash, was #{widget.class.name}" unless widget.is_a?(Hash)
      raise WidgetExceptions::InvalidWidget, "widget must have position and text keys" unless [:position, :text].all? {|k| widget.has_key?(k)}

      self_with_widgets = self_with_widgets.insert(widget[:position], widget[:text])
    end

    return self_with_widgets
  end
end

"Hello World".widget_inject([{position:2, text: "11"}, {position:4, text: "2222"}, {position: 6, text: "33"}]) #=> "He11ll2222o 33World"