Experimental parser: more tests, better key logic

tools/lexer_generator/automata_test.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 25 matching lines @@
   graph = parser.parse(string)
   nfa = NfaBuilder().nfa(graph)
   (start_name, dfa_nodes, end_nodes) = nfa.compute_dfa()
   dfa = Dfa(start_name, dfa_nodes, end_nodes)
   return (nfa, dfa)
 
 class AutomataTestCase(unittest.TestCase):
 
     # (pattern, should match, shouldn't match)
     __test_data = [
-      ("a", ["a"], ["b"]),
-      ("ab", ["ab"], ["bb"]),
-      ("a+b", ["ab", "aab", "aaab"], ["a", "b"]),
-      ("a?b", ["ab", "b"], ["a", "c"]),
-      ("a*b", ["ab", "aaab", "b"], ["a", "c"]),
-      ("a|b", ["a", "b"], ["ab", "c"]),
+      ("a", ["a"], ["b", ""]),
+      ("ab", ["ab"], ["bb", ""]),
+      ("a+b", ["ab", "aab", "aaab"], ["a", "b", ""]),
+      ("a?b", ["ab", "b"], ["a", "c", ""]),
+      ("a*b", ["ab", "aaab", "b"], ["a", "c", ""]),
+      ("a|b", ["a", "b"], ["ab", "c", ""]),
+      (".", ["a", "b"], ["", "aa"]),
+      (".*", ["", "a", "abcaabbcc"], []),
+      ("a.b", ["aab", "abb", "acb"], ["ab", ""]),
+      # ("a.?b", ["aab", "abb", "acb", "ab"], ["aaab", ""]),
+      # ("a.+b", ["aab", "abb", "acb", "ab"], ["aaab", ""]),
+      (".|.", ["a", "b"], ["aa", ""]),
     ]
 
     def test_matches(self):
-      for (regex, matches, not_matches) in AutomataTestCase.__test_data:
+      for (regex, matches, not_matches) in self.__test_data:
         (nfa, dfa) = build_automata(regex)
         for string in matches:
           self.assertTrue(nfa.matches(string))
           self.assertTrue(dfa.matches(string))
         for string in not_matches:
           self.assertFalse(nfa.matches(string))
           self.assertFalse(dfa.matches(string))
 
+    def test_can_construct_dot(self):
+      for (regex, matches, not_matches) in self.__test_data:
+        (nfa, dfa) = build_automata(regex)
+        nfa.to_dot()
+        dfa.to_dot()
+
 if __name__ == '__main__':
     unittest.main()