Experimental parser: refactor TransitionKey to use Term

tools/lexer_generator/transition_key_test.py

Index: tools/lexer_generator/transition_key_test.py
diff --git a/tools/lexer_generator/transition_key_test.py b/tools/lexer_generator/transition_key_test.py
index f64e0d02d2289917c5e7e5923c5be2632b70ba61..0b627c9306b3ccbb65618db1c75ee8cdddba8f47 100644
--- a/tools/lexer_generator/transition_key_test.py
+++ b/tools/lexer_generator/transition_key_test.py
@@ -48,6 +48,69 @@ class TransitionKeyTestCase(unittest.TestCase):
     for (left, right) in self.__equal_pairs:
       self.assertEqual(hash(left), hash(right))
 
+  def test_compare(self):
+    key = lambda x : TransitionKey.range(self.__encoding, x[0], x[1])
+    t_key = lambda x : TransitionKey.unique(x)
+    def check(a, b, expected):
+      self.assertEqual(expected, TransitionKey.compare(key(a), key(b)))
+      self.assertEqual(-expected, TransitionKey.compare(key(b), key(a)))
+    check([1,1], [1,1], 0)
+    check([1,3], [1,3], 0)
+    check([1,3], [4,5], -2)
+    check([1,4], [2,3], -3)
+    check([1,4], [2,4], -3)
+    check([1,3], [1,4], -4)
+    check([1,3], [2,4], -5)
+    check([1,3], [3,4], -5)
+    check([1,3], [3,4], -5)
+
+  def test_superset(self):
+    r_key = lambda a, b : TransitionKey.range(self.__encoding, a, b)
+    t_key = lambda x : TransitionKey.unique(x)
+    def merge(*keys):
+      return TransitionKey.merged_key(self.__encoding, keys)
+    def check(a, b, expected1, expected_none = None):
+      if expected1 == None:
+        expected2 = expected_none
+      elif expected1 == True:
+        expected2 = True if a == b else None
+      else:
+        expected2 = False  # disjoint sets remain disjoint
+      for expected in [expected1, expected2]:
+        try:
+          result = a.is_superset_of_key(b)
+        except Exception:
+          self.assertTrue(expected == None)
+          return
+        self.assertTrue(expected != None)
+        self.assertEqual(expected, result)
+        (a, b) = (b, a)
+    # subset cases
+    check(merge(r_key(1, 2), r_key(4, 5)), merge(r_key(1, 2)), True)
+    check(merge(r_key(1, 7), r_key(9, 10)), merge(r_key(3, 4)), True)
+    check(merge(r_key(1, 7), r_key(9, 10)),
+          merge(r_key(1, 7), r_key(9, 10)), True)
+    check(merge(r_key(1, 4)), merge(r_key(2, 3)), True)
+    # disjoint cases
+    check(merge(r_key(1, 4)), merge(r_key(5, 6)), False)
+    check(merge(t_key('t1')), merge(t_key('t2')), False)
+    check(merge(r_key(1, 4), t_key('t1')),
+          merge(r_key(5, 6), t_key('t2')), False)
+    check(merge(r_key(5, 6), t_key('t1')),
+          merge(r_key(1, 4), t_key('t2')), False)
+    # exception cases
+    check(merge(t_key('t1')), merge(t_key('t1'), t_key('t2')), None, True)
+    check(merge(t_key('t1'), t_key('t3')),
+          merge(t_key('t1'), t_key('t2')), None)
+    check(merge(t_key('t2'), t_key('t1')),
+          merge(t_key('t2'), t_key('t3')), None)
+    check(merge(r_key(1, 7), r_key(9, 10)),
+          merge(r_key(2, 8)), None)
+    check(merge(r_key(1, 7), r_key(9, 10)),
+          merge(r_key(10, 11)), None)
+    check(merge(r_key(1, 7), r_key(9, 10)),
+          merge(r_key(8, 9)), None)
+
   def test_classes(self):
     # class regex, should match, should not match
     data = [
@@ -85,9 +148,9 @@ class TransitionKeyTestCase(unittest.TestCase):
 
   def test_disjoint_keys(self):
     encoding = self.__encoding
-    key1 = TransitionKey(encoding, [(1, 10)])
-    key2 = TransitionKey(encoding, [(5, 15)])
-    disjoint_set = TransitionKey.disjoint_keys(encoding, set([key1, key2]))
-    self.assertTrue(TransitionKey(encoding, [(1, 4)]) in disjoint_set)
-    self.assertTrue(TransitionKey(encoding, [(5, 10)]) in disjoint_set)
-    self.assertTrue(TransitionKey(encoding, [(11, 15)]) in disjoint_set)
+    key = lambda x, y: TransitionKey.range(encoding, x , y)
+    disjoint_set = TransitionKey.disjoint_keys(encoding,
+                                               [key(1, 10), key(5, 15)])
+    self.assertTrue(key(1, 4) in disjoint_set)
+    self.assertTrue(key(5, 10) in disjoint_set)
+    self.assertTrue(key(11, 15) in disjoint_set)