Nice ascii-art DOM trees

tree.js

/**
tree.js - nice ascii-art DOM trees
usage: tree(element[, options]);
example:
var s = tree(document.body,{
	serialize: function(element){...}, // return a string representation such as "div#foo.bar"
	filter: function(element){...} // return false for any nodes to not include in tree
});
console.log(s);
*/

var tree = (function(){
	function ser(e){
		if(e.nodeType===1){
			var s = e.nodeName.toLowerCase();
			if(e.id){s+='#'+e.id;}
			if(e.className){s+='.'+e.className;}
			return s;
		} else if (e.nodeType===9) {
			return 'DOCUMENT';
		} else if (e.data) {
			return '#text';
		}
	}
	function isNode(e){
		return e.nodeType===1 || e.nodeType===9 || (e.nodeType===3 && e.data && wspatt.test(e.data));
	}
	var wspatt = /\S/;
	function converge(tNodes){
		if(tNodes.length){
			var txt = document.createTextNode(tNodes.map(function(t){
				return t.data;
			}).join(''));
			return txt;
		}else{
			return null;
		}
	}
	function getChildren(elmt, filter){
		var cNodes = elmt.childNodes;
		var children = [];
		for(var i=0;i<cNodes.length;i++){
			children.push(cNodes[i]);
		}
		children = children.filter(isNode).filter(filter);
		var result = [];
		var data = [];
		for(var i=0;i<children.length;i++){
			var e = children[i];
			if(e.nodeType === 3){
				data.push(e);
			}else{
				var tNode = converge(data);
				if(tNode){
					data.length = 0;
					result.push(tNode);
				}
				result.push(e);
			}
		}
		var tNode = converge(data);
		if(tNode)result.push(tNode);
		return result;
	}
	function makeTree(elmt, pstack, options, last){
		pstack.push({elmt:elmt,last:last});
		var str = pstack.map(function(o,i){
			if(i===0){return;}
			var cur=o.elmt===elmt;
			return cur
				? o.last ? '`-- ' : '|-- '
				: o.last ? '    ' : '|   '
			;
		}).join('');
		str += options.serialize(elmt);
		str += '\n';
		var children = getChildren(elmt, options.filter);
		var res = str + children.map(function(child, idx){
			return makeTree(
				child,
				pstack,
				options,
				idx===children.length-1
			);
		}).join('');
		pstack.pop();
		return res;
	}
	return function(elmt, options){
		options = options || {};
		return makeTree(elmt, [], {
			filter: options.filter || function(){return true;},
			serialize: options.serialize || ser
		}, true);
	};
})();

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