Fix for triply or greater nested fragments and trailing nullLine markers

public/doc-shredder/regionExtractor.js

@@ -17,10 +17,10 @@ module.exports = function regionExtractor() {
     lines.forEach(function(line, ix) {
       if (isCommentLine(line, commentPrefixes)) {
         if (hasRegionTag(line)) {
+          if (doc) docStack.push(doc);
           doc = {startIx: ix, regionName: getRegionName(line)};
           lines[ix] = nullLine;
           docs.push(doc);
-          docStack.push(doc);
         } else if (hasEndRegionTag(line)) {
           lines[ix] = nullLine;
           doc.endIx = ix;
@@ -38,8 +38,11 @@ module.exports = function regionExtractor() {
       }
       // eliminate all #docregion lines
       var rx = new RegExp(nullLine + '\n', 'g');
-      doc.content = content.replace(rx, '');
-
+      var content = content.replace(rx, '');
+      if (content.substr(-3) === nullLine) {
+        content = content.substr(0, content.length-3);
+      }
+      doc.content = content;
     });
     return docs;
   }

public/doc-shredder/test/test_source/app2.ts

@@ -0,0 +1,22 @@
+// #docregion
+// #docregion import
+import {Component, View, bootstrap} from 'angular2/angular2';
+// #enddocregion
+
+//#docregion class-w-annotations
+@Component({
+    selector: 'my-app'
+})
+@View({
+    template: '<h1 id="output">Hello, Angular 2!</h1>'
+})
+//#docregion class
+class MyAppComponent {
+}
+//#enddocregion
+//#enddocregion
+
+//#docregion bootstrap
+bootstrap(MyAppComponent);
+//#enddocregion
+//#enddocregion