Fix nested blockquote error

lib/marked.js

@@ -310,7 +310,7 @@ Lexer.prototype.token = function(src, top) {
 
       blockquote = cap[0].replace(/^ *> ?/gm, '');
       count = 1;
-      while (blockquote.match(/^ {0,3}>/)) {
+      while (linesMatch(blockquote, /^ {0,3}>/)) {
         count++;
         this.tokens.push({
           type: 'blockquote_start'
@@ -1188,7 +1188,7 @@ Parser.prototype.peek = function() {
 Parser.prototype.parseText = function() {
   var body = this.token.text;
 
-  while (this.peek().type === 'text') {
+  while (this.peek() && this.peek().type === 'text') {
     body += '\n' + this.next().text;
   }
 
@@ -1261,15 +1261,10 @@ Parser.prototype.tok = function() {
 
       body = '';
 
-      while (this.next().type !== 'blockquote_end') {
-        body += this.tok();
-      }
-
-      while (this.peek() && this.peek().type === 'blockquote_end') {
-        this.next();
-      }
-
-      for (i = 0; i < count; i++) {
+      while (count-- > 0) {
+        while (this.peek() && this.next().type !== 'blockquote_end') {
+          body += this.tok();
+        }
         body = this.renderer.blockquote(body);
       }
 
@@ -1280,7 +1275,7 @@ Parser.prototype.tok = function() {
       var ordered = this.token.ordered,
           start = this.token.start;
 
-      while (this.next().type !== 'list_end') {
+      while (this.peek() && this.next().type !== 'list_end') {
         body += this.tok();
       }
 
@@ -1296,7 +1291,7 @@ Parser.prototype.tok = function() {
         body += this.renderer.checkbox(checked);
       }
 
-      while (this.next().type !== 'list_item_end') {
+      while (this.peek() && this.next().type !== 'list_item_end') {
         body += !loose && this.token.type === 'text'
           ? this.parseText()
           : this.tok();
@@ -1516,6 +1511,17 @@ function splitCells(tableRow, count) {
   return cells;
 }
 
+function linesMatch(str, reg) {
+  var lines = str.split('\n');
+  for (var i = 0; i < lines.length; i++) {
+    if (!lines[i].match(reg)) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
 // Remove trailing 'c's. Equivalent to str.replace(/c*$/, '').
 // /c*$/ is vulnerable to REDOS.
 // invert: Remove suffix of non-c chars instead. Default falsey.

test/specs/new/nested_blockquote.html

@@ -0,0 +1,17 @@
+<blockquote>
+<p>a</p>
+<blockquote>
+<p>b</p>
+</blockquote>
+</blockquote>
+<blockquote>
+<blockquote>
+<p>c</p>
+</blockquote>
+</blockquote>
+<blockquote>
+<blockquote>
+<p>d</p>
+</blockquote>
+<p>e</p>
+</blockquote>

test/specs/new/nested_blockquote.md

@@ -0,0 +1,9 @@
+>a
+>
+>>b
+
+>>c
+
+>>d
+>
+>e