Limit element depth

lib/defaults.js

@@ -7,6 +7,7 @@ module.exports = {
   html: false,
   xhtml: false,
   breaks: false,
+  level: 10,
   langprefix: 'language-',
   highlight: function (/*str*/) { return ''; }
 };

lib/rules_block/blockquote.js

@@ -17,6 +17,8 @@ module.exports = function blockquote(state, startLine, endLine, silent) {
   // check the block quote marker
   if (state.src.charCodeAt(pos++) !== 0x3E/* > */) { return false; }
 
+  if (state.level >= state.options.level) { return false; }
+
   // we know that it's going to be a valid blockquote,
   // so no point trying to find the end of it in silent mode
   if (silent) { return true; }

lib/rules_block/list.js

@@ -100,6 +100,9 @@ module.exports = function list(state, startLine, endLine, silent) {
   } else {
     return false;
   }
+
+  if (state.level >= state.options.level) { return false; }
+
   // We should terminate list on style change. Remember first one to compare.
   markerCharCode = state.src.charCodeAt(posAfterMarker - 1);
 

lib/rules_inline/emphasis.js

@@ -124,6 +124,8 @@ module.exports = function emphasis(state/*, silent*/) {
     return true;
   }
 
+  if (state.level >= state.options.level) { return false; }
+
   oldLength = state.tokens.length;
   oldPending = state.pending;
   oldFlag = state.validateInsideEm;

lib/rules_inline/links.js

@@ -179,6 +179,7 @@ function links(state) {
   }
 
   if (marker !== 0x5B/* [ */) { return false; }
+  if (state.level >= state.options.level) { return false; }
 
   labelStart = start + 1;
   labelEnd = parseLinkLabel(state, start);