1// Copyright 2024 Christophe Henry
2// henry UNDERSCORE christophe AT hotmail DOT com
3// This is an extended version of the state machine available in the boost::mpl library
4// Distributed under the same license as the original.
5// Copyright for the original version:
6// Copyright 2005 David Abrahams and Aleksey Gurtovoy. Distributed
7// under the Boost Software License, Version 1.0. (See accompanying
8// file LICENSE_1_0.txt or copy at
9// http://www.boost.org/LICENSE_1_0.txt)
10
11// back-end
12#include <boost/msm/back/state_machine.hpp>
13//front-end
14#include <boost/msm/front/functor_row.hpp>
15#include <boost/msm/front/state_machine_def.hpp>
16#ifndef BOOST_MSM_NONSTANDALONE_TEST
17#define BOOST_TEST_MODULE back_many_deferred_transitions
18#endif
19#include <boost/test/unit_test.hpp>
20
21namespace msm = boost::msm;
22namespace msmf = boost::msm::front;
23namespace mpl = boost::mpl;
24
25namespace
26{
27 // ----- Events
28 struct Event1 {};
29 struct Event2 {};
30 struct Event3 {};
31 struct Event4 {};
32
33 // ----- State machine
34 struct Sm1_ :msmf::state_machine_def<Sm1_> {
35
36 // States
37 struct State1 :msmf::state<> {
38 template <class Event, class Fsm>
39 void on_entry(Event const&, Fsm&) const {
40 }
41 };
42 struct State2 :msmf::state<> {
43 template <class Event, class Fsm>
44 void on_entry(Event const&, Fsm&) const {
45 }
46 };
47 struct State3 :msmf::state<> {
48 template <class Event, class Fsm>
49 void on_entry(Event const&, Fsm&) const {
50 }
51 };
52 struct State4 :msmf::state<> {
53 template <class Event, class Fsm>
54 void on_entry(Event const&, Fsm&) const {
55 }
56 };
57 struct State5 :msmf::state<> {
58 template <class Event, class Fsm>
59 void on_entry(Event const&, Fsm&) const {
60 }
61 };
62 // Set initial state
63 typedef State1 initial_state;
64 // Enable deferred capability
65 typedef int activate_deferred_events;
66 // Transition table
67 struct transition_table :mpl::vector<
68 // Start Event Next Action Guard
69 msmf::Row < State1, Event1, msmf::none, msmf::Defer>,
70 msmf::Row < State1, Event2, msmf::none, msmf::Defer>,
71 msmf::Row < State1, Event3, msmf::none, msmf::Defer>,
72 msmf::Row < State1, Event4, State2 , msmf::none>,
73
74 msmf::Row < State2, Event3, msmf::none, msmf::Defer>,
75 msmf::Row < State2, Event1, msmf::none, msmf::Defer>,
76 msmf::Row < State2, Event2, State3 , msmf::none>,
77
78 msmf::Row < State3, Event1, State4 , msmf::none>,
79 msmf::Row < State3, Event3, State5 , msmf::none>,
80 msmf::Row < State4, Event3, State5 , msmf::none>,
81 msmf::Row < State5, Event1, State4 , msmf::none>
82 > {};
83
84 template <class Fsm, class Event>
85 void no_transition(Event const&, Fsm&, int /*state*/) {
86 }
87 };
88
89 // Pick a back-end
90 typedef msm::back::state_machine<Sm1_> Sm1;
91
92
93 BOOST_AUTO_TEST_CASE(back_many_deferred_transitions)
94 {
95 Sm1 sm1;
96 sm1.start();
97 sm1.process_event(evt: Event1());
98 sm1.process_event(evt: Event2());
99 sm1.process_event(evt: Event3());
100 sm1.process_event(evt: Event4());
101
102 BOOST_CHECK_MESSAGE(sm1.current_state()[0] == 4, "State5 should be active");
103 }
104}
105
106

source code of boost/libs/msm/test/ManyDeferTransitions.cpp