[PROTON-1674] [cpp] Container does no longer wait for planned scheduled tasks

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: proton-c-0.18.1
• Component/s: cpp-binding
• Labels: test testing
• Assignee: Justin Ross
• Reporter: Jiri Daněk
• Created: 03/Nov/17 09:17
• Updated: 02/May/18 22:04

Description

In the following test, what now seems to be happening is that the container exits before the scheduled task is executed. Therefore, no exception is thrown.

class MyException : public std::exception {};

struct exception_from_scheduled_tester : public proton::messaging_handler {
    proton::listener listener;
    test_port port;
    bool should_stop;

    explicit exception_from_scheduled_tester(bool should_stop) : should_stop(should_stop) {}

    void on_container_start(proton::container& c) PN_CPP_OVERRIDE {
        listener = c.listen(port.url());
        c.connect(port.url("localhost"));
        c.schedule(proton::duration(250), [this]() {
            throw MyException();
        });
        if (should_stop) {
            c.stop();
        }
    }
};

int test_container_scheduled_throws_exception() {
    exception_from_scheduled_tester t(/*should_stop*/ true);  // test would pass if this is set to false
    proton::container c(t);
    try {
        c.run();
        FAIL("expected exception");
    } catch (proton::error &e) {
        // expected
    }
//    t.listener.stop(); // uh, why am I not supposed to call this here?
    return 0;
}

According to git bisect, the commit that changed the behavior (flipped the test from pass to fail) is

% git bisect bad 
6e41df90023cfc06f4bc9ad7b972e9b39284980a is the first bad commit
commit 6e41df90023cfc06f4bc9ad7b972e9b39284980a
Author: Alan Conway <[e-mail]>
Date:   Mon Oct 23 17:24:10 2017 +0100

    PROTON-1628: [cpp] Stopping container in on_container_start will hang
    
    Check if already stopping before entering the event loop in container::impl::thread()

:040000 040000 ffad13af832b4c8c9b15a75a146ba1cec302492f 4bde1331bba40d477eefa383d78a95d49a291a90 M      proton-c

Issue Links

• blocks: PROTON-1676 Check that scheduled tasks are executed, despite closed connection or stopped container
• relates to: PROTON-1628 [cpp] Stopping container in on_container_start will hang