support gitiles auto-linking

tools/md_browser/gitiles_autolink.py

Index: tools/md_browser/gitiles_autolink.py
diff --git a/tools/md_browser/gitiles_autolink.py b/tools/md_browser/gitiles_autolink.py
new file mode 100644
index 0000000000000000000000000000000000000000..5cfeb21313ea2a0d809bf3dab3ff056365be3c00
--- /dev/null
+++ b/tools/md_browser/gitiles_autolink.py
@@ -0,0 +1,28 @@
+# Copyright 2017 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Implements Gitiles' simpler auto linking.
+
+This extention auto links basic URLs that aren't bracketed by <...>.
+
+https://gerrit.googlesource.com/gitiles/+/master/gitiles-servlet/src/main/java/com/google/gitiles/Linkifier.java
+"""
+
+from markdown.inlinepatterns import (AutolinkPattern, Pattern)
+from markdown.extensions import Extension
+
+
+AUTOLINK_RE = r'([Hh][Tt][Tt][Pp][Ss]?://[^>]*)'
+
+
+class _GitilesSmartQuotesExtension(Extension):
+  """Add Gitiles' simpler linkifier to Markdown."""
+  def extendMarkdown(self, md, md_globals):
+    md.inlinePatterns.add('gitilesautolink',
+                          AutolinkPattern(AUTOLINK_RE, md),
+                          '<autolink')
+
+
+def makeExtension(*args, **kwargs):
+  return _GitilesSmartQuotesExtension(*args, **kwargs)