Merge branch 'atx-tabs' of https://github.com/OrangeShark/commonmark.js into OrangeShark-atx-tabs

Author: jgm

lib/blocks.js

@@ -430,7 +430,7 @@ var blockStarts = [
             container.level = match[0].trim().length; // number of #s
             // remove trailing ###s:
             container._string_content =
-                parser.currentLine.slice(parser.offset).replace(/^ *#+ *$/, '').replace(/ +#+ *$/, '');
+                parser.currentLine.slice(parser.offset).replace(/^[ \t]*#+[ \t]*$/, '').replace(/[ \t]+#+[ \t]*$/, '');
             parser.advanceOffset(parser.currentLine.length - parser.offset);
             return 2;
         } else {

test/regression.txt

@@ -87,3 +87,10 @@ Issue jgm/commonmark.js#121 - punctuation set different
 .
 <p>^<em>test</em></p>
 ````````````````````````````````
+
+Issue #116 - tabs before and after ATX closing heading
+```````````````````````````````` example
+# foo→#→
+.
+<h1>foo</h1>
+````````````````````````````````