testing: coroutinize test_runner::start_thread()

for better readability

Signed-off-by: Kefu Chai <[email protected]>

src/testing/test_runner.cc

@@ -74,39 +74,36 @@ bool test_runner::start_thread(int ac, char** av) {
             ("fail-on-abandoned-failed-futures", bpo::value<bool>()->default_value(true), "Fail the test if there are any abandoned failed futures");
         // We guarantee that only one thread is running.
         // We only read this after that one thread is joined, so this is safe.
-        _exit_code = app.run(ac, av, [this, &app, init_outcome = init_outcome.get()] {
+        _exit_code = app.run(ac, av, [this, &app, init_outcome = init_outcome.get()] () -> future<int> {
             init_outcome->give(true);
-            auto init = [&app] {
+
+            // TODO: fix the indent
                 auto conf_seed = app.configuration()["random-seed"];
                 auto seed = conf_seed.empty() ? std::random_device()():  conf_seed.as<unsigned>();
                 std::cout << "random-seed=" << seed << std::endl;
-                return smp::invoke_on_all([seed] {
+                co_await smp::invoke_on_all([seed] {
                     auto local_seed = seed + this_shard_id();
                     local_random_engine.seed(local_seed);
                 });
-            };
 
-            return init().then([this] {
-              return do_until([this] { return _done; }, [this] {
-                // this will block the reactor briefly, but we don't care
-                try {
-                    auto func = _task.take();
-                    return func();
-                } catch (const stop_execution&) {
-                    _done = true;
-                    return make_ready_future<>();
-                }
-              }).or_terminate();
-            }).then([&app] {
+            for (;;) {
+              // this will block the reactor briefly, but we don't care
+              try {
+                  auto func = _task.take();
+                  co_await func().or_terminate();
+              } catch (const stop_execution&) {
+                  break;
+              }
+            }
+            // TODO: fix the indent
                 if (engine().abandoned_failed_futures()) {
                     std::cerr << "*** " << engine().abandoned_failed_futures() << " abandoned failed future(s) detected" << std::endl;
                     if (app.configuration()["fail-on-abandoned-failed-futures"].as<bool>()) {
                         std::cerr << "Failing the test because fail was requested by --fail-on-abandoned-failed-futures" << std::endl;
-                        return 3;
+                        co_return 3;
                     }
                 }
-                return 0;
-            });
+                co_return 0;
         });
         init_outcome->give(false);
     });