Merge multiple comment tokens into a single one.

The tokens T_COMMENT_START, T_TEXT and T_COMMENT_END have been merged into a
single token: T_COMMENT. This simplifies both the lexer and the parser.

ext/ragel/base_lexer.rl

@@ -149,21 +149,6 @@
     comment_start = '<!--';
     comment_end   = '-->';
 
-    action start_comment {
-        callback_simple("on_comment_start");
-        fcall comment;
-    }
-
-    # Machine used for processing the contents of a comment. Everything
-    # inside a comment is treated as plain text (similar to CDATA tags).
-    comment := |*
-        any* comment_end => {
-            callback("on_text", data, encoding, ts, te - 3);
-            callback_simple("on_comment_end");
-            fret;
-        };
-    *|;
-
     # XML declaration tags
     #
     # http://www.w3.org/TR/REC-xml/#sec-prolog-dtd
@@ -257,9 +242,12 @@
         '<'            => start_element;
         doctype_start  => start_doctype;
         cdata_start    => start_cdata;
-        comment_start  => start_comment;
         xml_decl_start => start_xml_decl;
 
+        comment_start any* comment_end => {
+            callback("on_comment", data, encoding, ts + 4, te - 3);
+        };
+
         # Enter the body of the tag. If HTML mode is enabled and the current
         # element is a void element we'll close it and bail out.
         '>' => {

lib/oga/xml/lexer.rb

@@ -217,17 +217,12 @@ module Oga
       end
 
       ##
-      # Called on the start of a comment.
+      # Called on a comment.
       #
-      def on_comment_start
-        add_token(:T_COMMENT_START)
-      end
-
-      ##
-      # Called on the end of a comment.
+      # @param [String] value
       #
-      def on_comment_end
-        add_token(:T_COMMENT_END)
+      def on_comment(value)
+        add_token(:T_COMMENT, value)
       end
 
       ##

lib/oga/xml/parser.y

@@ -12,8 +12,7 @@ class Oga::XML::Parser
 token T_STRING T_TEXT
 token T_DOCTYPE_START T_DOCTYPE_END T_DOCTYPE_TYPE T_DOCTYPE_NAME
 token T_DOCTYPE_INLINE
-token T_CDATA_START T_CDATA_END
-token T_COMMENT_START T_COMMENT_END
+token T_CDATA_START T_CDATA_END T_COMMENT
 token T_ELEM_START T_ELEM_NAME T_ELEM_NS T_ELEM_END T_ATTR
 token T_XML_DECL_START T_XML_DECL_END
 
@@ -92,11 +91,8 @@ rule
   # Comments
 
   comment
-    # <!---->
-    : T_COMMENT_START T_COMMENT_END { on_comment }
-
     # <!-- foo -->
-    | T_COMMENT_START T_TEXT T_COMMENT_END { on_comment(val[1]) }
+    | T_COMMENT { on_comment(val[0]) }
     ;
 
   # Elements

spec/oga/xml/lexer/comments_spec.rb

@@ -3,33 +3,20 @@ require 'spec_helper'
 describe Oga::XML::Lexer do
   context 'comments' do
     example 'lex a comment' do
-      lex('<!-- foo -->').should == [
-        [:T_COMMENT_START, nil, 1],
-        [:T_TEXT, ' foo ', 1],
-        [:T_COMMENT_END, nil, 1]
-      ]
+      lex('<!-- foo -->').should == [[:T_COMMENT, ' foo ', 1]]
     end
 
     example 'lex a comment containing --' do
-      lex('<!-- -- -->').should == [
-        [:T_COMMENT_START, nil, 1],
-        [:T_TEXT, ' -- ', 1],
-        [:T_COMMENT_END, nil, 1]
-      ]
+      lex('<!-- -- -->').should == [[:T_COMMENT, ' -- ', 1]]
     end
 
     example 'lex a comment containing ->' do
-      lex('<!-- -> -->').should == [
-        [:T_COMMENT_START, nil, 1],
-        [:T_TEXT, ' -> ', 1],
-        [:T_COMMENT_END, nil, 1]
-      ]
+      lex('<!-- -> -->').should == [[:T_COMMENT, ' -> ', 1]]
     end
 
     example 'lex a comment followed by text' do
       lex('<!---->foo').should == [
-        [:T_COMMENT_START, nil, 1],
-        [:T_COMMENT_END, nil, 1],
+        [:T_COMMENT, '', 1],
         [:T_TEXT, 'foo', 1]
       ]
     end
@@ -37,8 +24,7 @@ describe Oga::XML::Lexer do
     example 'lex text followed by a comment' do
       lex('foo<!---->').should == [
         [:T_TEXT, 'foo', 1],
-        [:T_COMMENT_START, nil, 1],
-        [:T_COMMENT_END, nil, 1]
+        [:T_COMMENT, '', 1]
       ]
     end
 
@@ -47,8 +33,7 @@ describe Oga::XML::Lexer do
         [:T_ELEM_START, nil, 1],
         [:T_ELEM_NAME, 'p', 1],
         [:T_ELEM_END, nil, 1],
-        [:T_COMMENT_START, nil, 1],
-        [:T_COMMENT_END, nil, 1]
+        [:T_COMMENT, '', 1]
       ]
     end
   end