anchor.diff:        }
       }
   
  -    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) {
  
positive.code:         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:
  
negative.code: 
    @override
    @failingTest
    void test_double_missingDigitInExponent() {
      // TODO(paulberry,ahe): see UnimplementedError("distinguish unterminated
      // errors")
  