Function TEST

3rdparty/libprocess/src/tests/state_machine_tests.cpp:42–108

TEST(StateMachineTest, Transition)
{
  StateMachine<State> state(State::INITIAL);

  Try<int> i = state.transition<State::INITIAL, State::STARTING>(
      []() {
        return 42;
      });

  EXPECT_SOME_EQ(42, i);

  Try<Nothing> error = state.transition<State::INITIAL, State::STARTING>();

  EXPECT_ERROR(error);

  Try<Try<int>> t = state.transition<State::STARTING, State::RUNNING>(
      []() -> Try<int> {
        return 42;
      });

  ASSERT_SOME(t);
  EXPECT_SOME_EQ(42, t.get());

  error = state.transition<State::STARTING, State::RUNNING>();

  EXPECT_ERROR(error);

  t = state.transition<State::RUNNING, State::STOPPING>(
      []() -> Try<int> {
        return Error("Error");
      });

  ASSERT_SOME(t);
  ASSERT_ERROR(t.get());
  EXPECT_EQ("Error", t->error());

  error = state.transition<State::RUNNING, State::STOPPING>();

  EXPECT_ERROR(error);

  Promise<int> promise;

  Try<Future<int>> f = state.transition<State::STOPPING, State::STOPPED>(
      [&]() -> Future<int> {
        return promise.future();
      });

  ASSERT_SOME(f);
  EXPECT_TRUE(f->isPending());

  promise.set(42);

  AWAIT_EXPECT_EQ(42, f.get());

  error = state.transition<State::STOPPING, State::STOPPED>();

  EXPECT_ERROR(error);