Experimental parser: split off dot processing

tools/lexer_generator/automaton.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 127 matching lines @@
       last_position = pos
       # lex next token
       valid_states = Automaton.__transition_states_for_char(self.start_set(), c)
       assert valid_states
     valid_states = self.epsilon_closure(valid_states)
     action = Action.dominant_action(valid_states)
     if not action:
       assert default_action
       action = default_action
     yield (action, last_position, len(string))
-
-  def to_dot(self):
-
-    def escape(v):
-      v = str(v)
-      v = v.replace('\r', '\\\\r').replace('\t', '\\\\t').replace('\n', '\\\\n')
-      v = v.replace('\\', '\\\\').replace('\"', '\\\"')
-      return v
-
-    def f(node, (node_content, edge_content)):
-      if node.action():
-        action_text = escape(node.action())
-        node_content.append('  S_l%s[shape = box, label="%s"];' %
-                            (node.node_number(), action_text))
-        node_content.append('  S_%s -> S_l%s [arrowhead = none];' %
-                            (node.node_number(), node.node_number()))
-      for key, state in node.key_state_iter():
-        if key == TransitionKey.epsilon():
-          key = "ε"
-        else:
-          key = key.to_string(self.encoding())
-        edge_content.append("  S_%s -> S_%s [ label = \"%s\" ];" % (
-            node.node_number(), state.node_number(), escape(key)))
-      return (node_content, edge_content)
-
-    (node_content, edge_content) = self.visit_all_states(f, ([], []))
-
-    start_set = self.start_set()
-    assert len(start_set) == 1
-    start_node = iter(start_set).next()
-    terminal_set = self.terminal_set()
-
-    terminals = ["S_%d;" % x.node_number() for x in terminal_set]
-    start_number = start_node.node_number()
-    start_shape = "circle"
-    if start_node in terminal_set:
-      start_shape = "doublecircle"
-
-    return '''
-digraph finite_state_machine {
-  rankdir=LR;
-  node [shape = %s, style=filled, bgcolor=lightgrey]; S_%s
-  node [shape = doublecircle, style=unfilled]; %s
-  node [shape = circle];
-%s
-%s
-}
-    ''' % (start_shape,
-           start_number,
-           " ".join(terminals),
-           "\n".join(edge_content),
-           "\n".join(node_content))