Experimental parser: fixup unit tests

tools/lexer_generator/regex_parser.py

 # Copyright 2013 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 117 matching lines @@
 
   def p_maybe_class_content(self, p):
     '''maybe_class_content : class_content
                            | empty'''
     p[0] = p[1]
 
   def p_empty(self, p):
     'empty :'
 
   def p_error(self, p):
-    raise Exception("Syntax error in input '%s'" % p)
+    raise Exception("Syntax error in input '%s'" % str(p))
 
   @staticmethod
   def __cat(left, right):
     if right == None:
       return left
     return ('CAT', left, right)
 
   def build(self, **kwargs):
     self.parser = yacc.yacc(module=self, debug=0, write_tables=0, **kwargs)
     self.lexer = RegexLexer()
     self.lexer.build(**kwargs)
 
   __static_instance = None
   @staticmethod
   def parse(data):
     parser = RegexParser.__static_instance
     if not parser:
       parser = RegexParser()
       parser.build()
       RegexParser.__static_instance = parser
-    return parser.parser.parse(data, lexer=parser.lexer.lexer)
+    try:
+      return parser.parser.parse(data, lexer=parser.lexer.lexer)
+    except Exception as e:
+      RegexParser.__static_instance = None
+      raise e