Use token.value to distinguish comment types.

pkg/front_end/test/scanner_test.dart

 // Copyright (c) 2016, 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.
 
 import 'package:front_end/src/base/errors.dart';
 import 'package:front_end/src/base/jenkins_smi_hash.dart';
 import 'package:front_end/src/fasta/scanner/error_token.dart' as fasta;
 import 'package:front_end/src/fasta/scanner/keyword.dart' as fasta;
 import 'package:front_end/src/fasta/scanner/string_scanner.dart' as fasta;
 import 'package:front_end/src/fasta/scanner/token.dart' as fasta;
@@ skipping 207 matching lines @@
   @override
   @failingTest
   void test_comment_multi_unterminated() {
     // TODO(paulberry,ahe): see UnimplementedError("distinguish unterminated
     // errors")
     super.test_comment_multi_unterminated();
   }
 
   @override
   @failingTest
-  void test_comment_single() {
-    // TODO(paulberry,ahe): See TODO comment below in _translateTokenInfoKind().
-    super.test_comment_single();
-  }
-
-  @override
-  @failingTest
   void test_double_missingDigitInExponent() {
     // TODO(paulberry,ahe): see UnimplementedError("distinguish unterminated
     // errors")
     super.test_double_missingDigitInExponent();
   }
 
   @override
   @failingTest
   void test_hexidecimal_missingDigit() {
     // TODO(paulberry,ahe): see UnimplementedError("distinguish unterminated
@@ skipping 146 matching lines @@
     CommentToken currentCommentHead;
     CommentToken currentCommentTail;
     while (true) {
       if (token is fasta.ErrorToken) {
         var error = _translateErrorToken(token, source.length);
         if (error != null) {
           listener.errors.add(error);
         }
       } else if (token is fasta.StringToken &&
           token.info.kind == fasta.COMMENT_TOKEN) {
-        var translatedToken = _translateToken(token, null) as CommentToken;
+        // TODO(paulberry,ahe): It would be nice if the scanner gave us an
+        // easier way to distinguish between the two types of comment.
+        var type = token.value.startsWith('/*')
+            ? TokenType.MULTI_LINE_COMMENT
+            : TokenType.SINGLE_LINE_COMMENT;
+        var translatedToken =
+            new CommentToken(type, token.value, token.charOffset);
         if (currentCommentHead == null) {
           currentCommentHead = currentCommentTail = translatedToken;
         } else {
           currentCommentTail.setNext(translatedToken);
           currentCommentTail = translatedToken;
         }
       } else {
         var translatedToken = _translateToken(token, currentCommentHead);
         translatedToken.setNext(translatedToken);
         currentCommentHead = currentCommentTail = null;
@@ skipping 72 matching lines @@
     }
 
     Token makeBeginToken() {
       if (comment == null) {
         return new BeginToken(type, offset);
       } else {
         return new BeginTokenWithComment(type, offset, comment);
       }
     }
 
-    Token makeCommentToken() {
-      return new CommentToken(type, token.value, offset);
-    }
-
     if (token is fasta.StringToken) {
-      if (token.info.kind == fasta.COMMENT_TOKEN) {
-        return makeCommentToken();
-      } else {
-        return makeStringToken(token.value);
-      }
+      return makeStringToken(token.value);
     } else if (token is fasta.KeywordToken) {
       return makeKeywordToken(_translateKeyword(token.keyword.syntax));
     } else if (token is fasta.SymbolToken) {
       if (token is fasta.BeginGroupToken) {
         if (type == TokenType.LT) {
           return makeStringToken(token.value);
         } else {
           return makeBeginToken();
         }
       } else {
@@ skipping 132 matching lines @@
       case fasta.TILDE_SLASH_EQ_TOKEN:
         return TokenType.TILDE_SLASH_EQ;
       case fasta.TILDE_SLASH_TOKEN:
         return TokenType.TILDE_SLASH;
       case fasta.PERCENT_EQ_TOKEN:
         return TokenType.PERCENT_EQ;
       case fasta.GT_GT_TOKEN:
         return TokenType.GT_GT;
       case fasta.CARET_EQ_TOKEN:
         return TokenType.CARET_EQ;
-      case fasta.COMMENT_TOKEN:
-        // TODO(paulberry,ahe): how to distinguish multi-line from
-        // single-line comments?  Causes a failure in test_comment_single().
-        return TokenType.MULTI_LINE_COMMENT;
       case fasta.STRING_INTERPOLATION_IDENTIFIER_TOKEN:
         return TokenType.STRING_INTERPOLATION_IDENTIFIER;
       case fasta.QUESTION_PERIOD_TOKEN:
         return TokenType.QUESTION_PERIOD;
       case fasta.QUESTION_QUESTION_TOKEN:
         return TokenType.QUESTION_QUESTION;
       case fasta.QUESTION_QUESTION_EQ_TOKEN:
         return TokenType.QUESTION_QUESTION_EQ;
       default:
         throw new UnimplementedError('$kind');
@@ skipping 1200 matching lines @@
   _TestScanner(CharacterReader reader, [this.listener]) : super(reader);
 
   @override
   void reportError(
       ScannerErrorCode errorCode, int offset, List<Object> arguments) {
     if (listener != null) {
       listener.errors.add(new _TestError(offset, 1, errorCode, arguments));
     }
   }
 }