Added support for parsing comments.

lib/oga/parser.y

@@ -4,6 +4,7 @@ token T_NEWLINE T_SPACE
 token T_STRING T_TEXT
 token T_DOCTYPE_START T_DOCTYPE_END T_DOCTYPE_TYPE
 token T_CDATA_START T_CDATA_END
+token T_COMMENT_START T_COMMENT_END
 
 options no_result_var
 
@@ -21,6 +22,7 @@ rule
   expression
     : doctype
     | cdata
+    | comment
     ;
 
   # Doctypes
@@ -58,6 +60,16 @@ rule
     | T_CDATA_START T_TEXT T_CDATA_END { s(:cdata, val[1]) }
     ;
 
+  # Comments
+
+  comment
+    # <!---->
+    : T_COMMENT_START T_COMMENT_END { s(:comment) }
+
+    # <!-- foo -->
+    | T_COMMENT_START T_TEXT T_COMMENT_END { s(:comment, val[1]) }
+    ;
+
   whitespaces
     : whitespaces whitespace
     | whitespace

spec/oga/parser/comments_spec.rb

@@ -0,0 +1,13 @@
+require 'spec_helper'
+
+describe Oga::Parser do
+  context 'comments' do
+    example 'parse an empty comment' do
+      parse_html('<!---->').should == s(:document, s(:comment))
+    end
+
+    example 'parse a comment' do
+      parse_html('<!--foo-->').should == s(:document, s(:comment, 'foo'))
+    end
+  end
+end