test: add test.Scheduler (#58)

When simulating execution of core.Consensus by passing packets through golang-channel or real-socket, we need to utilize time.Sleep and time.Now to simulate the required network/proposing latency. It's problematic when we try to test a simulation with long network latency.

Instead, Scheduler would try to execute the event with minimum timestamp, thus time.Sleep is replaced with Scheduler.nextTick, and time.Now is replaced with Event.Time.

Changes:
- Add test.Scheduler.
- Add test.Stopper interface to provide encapsulate different stop conditions for scheduler.
- Add a reference implementation for test.Stopper, it will stop scheduler when all validators confirmed X blocks proposed from themselves.
- Add a test scenario on core.Consensus that all validators are not byzantine.

1 files changed, 12 insertions, 0 deletions

diff --git a/core/test/app.go b/core/test/app.go
index aedcba9..5c438a7 100644
--- a/core/test/app.go
+++ b/core/test/app.go
@@ -191,3 +191,15 @@ Loop:
 	}
 	return nil
 }
+
+// Check provides a backdoor to check status of App with reader lock.
+func (app *App) Check(checker func(*App)) {
+	app.ackedLock.RLock()
+	defer app.ackedLock.RUnlock()
+	app.totalOrderedLock.RLock()
+	defer app.totalOrderedLock.RUnlock()
+	app.deliveredLock.RLock()
+	defer app.deliveredLock.RUnlock()
+
+	checker(app)
+}