ticker/ticker_test: adds Ticker interface tests

ticker/ticker_test.go

@@ -0,0 +1,99 @@
+package ticker_test
+
+import (
+	"testing"
+	"time"
+
+	"github.com/lightningnetwork/lnd/ticker"
+)
+
+const interval = 50 * time.Millisecond
+const numActiveTicks = 3
+
+var tickers = []struct {
+	name   string
+	ticker ticker.Ticker
+}{
+	{
+		"default ticker",
+		ticker.New(interval),
+	},
+	{
+		"mock ticker",
+		ticker.MockNew(interval),
+	},
+}
+
+// TestTickers verifies that both our production and mock tickers exhibit the
+// same principle behaviors when accessed via the ticker.Ticker interface
+// methods.
+func TestInterfaceTickers(t *testing.T) {
+	for _, test := range tickers {
+		t.Run(test.name, func(t *testing.T) {
+			testTicker(t, test.ticker)
+		})
+	}
+}
+
+// testTicker asserts the behavior of a freshly initialized ticker.Ticker.
+func testTicker(t *testing.T, ticker ticker.Ticker) {
+	// Newly initialized ticker should start off inactive.
+	select {
+	case <-ticker.Ticks():
+		t.Fatalf("ticker should not have ticked before calling Resume")
+	case <-time.After(2 * interval):
+	}
+
+	// Resume, ticker should be active and start sending ticks.
+	ticker.Resume()
+
+	for i := 0; i < numActiveTicks; i++ {
+		select {
+		case <-ticker.Ticks():
+		case <-time.After(2 * interval):
+			t.Fatalf(
+				"ticker should have ticked after calling Resume",
+			)
+		}
+	}
+
+	// Pause, check that ticker is inactive and sends no ticks.
+	ticker.Pause()
+
+	select {
+	case <-ticker.Ticks():
+		t.Fatalf("ticker should not have ticked after calling Pause")
+	case <-time.After(2 * interval):
+	}
+
+	// Pause again, expect same behavior as after first invocation.
+	ticker.Pause()
+
+	select {
+	case <-ticker.Ticks():
+		t.Fatalf("ticker should not have ticked after calling Pause again")
+	case <-time.After(2 * interval):
+	}
+
+	// Resume again, should result in normal active behavior.
+	ticker.Resume()
+
+	for i := 0; i < numActiveTicks; i++ {
+		select {
+		case <-ticker.Ticks():
+		case <-time.After(2 * interval):
+			t.Fatalf(
+				"ticker should have ticked after calling Resume",
+			)
+		}
+	}
+
+	// Stop the ticker altogether, should render it inactive.
+	ticker.Stop()
+
+	select {
+	case <-ticker.Ticks():
+		t.Fatalf("ticker should not have ticked after calling Stop")
+	case <-time.After(2 * interval):
+	}
+}