Ancestry climber jQuery plugin

jquery.climb-ancestry.coffee

###
jQuery Ancestry Climber Plugin

Defines a class that traces an element's ancestry, executing
a callback on each ancestor.
###

class AncestryClimber
  constructor: (@elem, @callback = $.noop) ->
    throw new Error 'Please supply a DOM element' unless @elem
    throw new Error 'Please supply a callback function' unless @callback
    @$elem      = $(@elem)
    @iterations = 0

  climbLevel: (skipStop = true) ->
    @iterations += 1

    $parent = @$elem.parent()
    stop    = @callback.call(@$elem, @iterations) is false
    stop    = false if skipStop
    @$elem  = $parent

    if not stop and $parent[0].nodeName isnt '#document'
      @climbLevel false

return window.AncestryClimber = AncestryClimber if typeof(jQuery) is 'undefined'

$.fn.extend climbAncestry: (cb) ->
  climber = new AncestryClimber $(this), cb
  climber.climbLevel()
  this