getNodesByType

/*global document*/
//a function to get DOM nodes by nodeType property.
//If you do not supply a value I will give you every DOM node.
//
//example:
// var allComments = document.getNodesByType(8);
// or
// var allComments = document.getNodesByType("COMMENT_NODE");
//
//The accepted string values are the actual node type names, so that the
//typeValue argument can be supplied dynamically from other code.
//
//
// Please try http://prettydiff.com/ for all your web development needs!
//
//
//Keep in mind that the following node types are valid in the W3C DOM
//standards, but have been deprecated in the WHATWG DOM specification.
//
// 2 - ATTRIBUTE_NODE
// 4 - CDATA_SECTION_NODE
// 5 - ENTITY_REFERENCE_NODE
// 6 - ENTITY_NODE
// 12 - NOTATION_NODE
//
//This means all node types are still valid in the standard, but the
//deprecated types may not be retrievable from certain DOM
//implementations.
//
;(function(doc) {
  doc.getNodesByType = function (typeValue) {
    'use strict';

    var types = 0,
      typeList = {
        'ALL': 0,
        'ELEMENT_NODE': 1,
        'ATTRIBUTE_NODE': 2,
        'TEXT_NODE': 3,
        'CDATA_SECTION_NODE': 4,
        'ENTITY_REFERENCE_NODE': 5,
        'ENTITY_NODE': 6,
        'PROCESSING_INSTRUCTION_NODE': 7,
        'COMMENT_NODE': 8,
        'DOCUMENT_NODE': 9,
        'DOCUMENT_TYPE_NODE': 10,
        'DOCUMENT_FRAGMENT_NODE': 11,
        'NOTATION_NODE': 12
      };

    if (typeValue in typeList) {
      types = typeList[typeValue];
    } else {
      types = parseInt(typeValue, 10);
    }

    return (function () {
      var root = doc.documentElement,
        output = [],
        child = function (x) {
          var a = x.childNodes,
            b = a.length,
            c = 0;

          for (c = 0; c < b; c += 1) {
            if (a[c].nodeType === types || types === 0) output.push(a[c]);
            if (a[c].nodeType === 1) child(a[c]);
          }
        };
    
      if (types === 1 || types === 0) output.push(root);
    
      child(root);
    
      return output;
    }());
  };
}(document));