Allow resolving links that contain inline syntax.

lib/src/inline_parser.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library markdown.inline_parser;
 
 import 'ast.dart';
 import 'document.dart';
 import 'util.dart';
 
@@ skipping 262 matching lines @@
 
   Node createNode(InlineParser parser, Match match, TagState state) {
     // If we didn't match refLink or inlineLink, then it means there was
     // nothing after the first square bracket, so it isn't a normal markdown
     // link at all. Instead, we allow users of the library to specify a special
     // resolver function ([linkResolver]) that may choose to handle
     // this. Otherwise, it's just treated as plain text.
     if (isNullOrEmpty(match[1])) {
       if (linkResolver == null) return null;
 
-      // Only allow implicit links if the content is just text.
-      // TODO(rnystrom): Do we want to relax this?
-      if (state.children.any((child) => child is! Text)) return null;
-      // If there are multiple children, but they are all text, send the
-      // combined text to linkResolver.
-      var textToResolve =
-          state.children.fold('', (oldVal, child) => oldVal + child.text);
+      // Treat the contents as unparsed text even if they happen to match. This
+      // way, we can handle things like [LINK_WITH_UNDERSCORES] as a link and
+      // not get confused by the emphasis.
+      var textToResolve = parser.source.substring(state.endPos, parser.pos);
 
       // See if we have a resolver that will generate a link for us.
       resolved = true;
       return linkResolver(textToResolve);
     } else {
       Link link = getLink(parser, match, state);
       if (link == null) return null;
 
       final Element node = new Element('a', state.children)
         ..attributes["href"] = escapeHtml(link.url)
@@ skipping 141 matching lines @@
       parser.consume(endMatch[0].length);
     } else {
       // Didn't close correctly so revert to text.
       parser.start = startPos;
       parser.advanceBy(endMatch[0].length);
     }
 
     return null;
   }
 }