test slot ticker

tests/plugins/eth2/beacon/test_slot_ticker.py

@@ -0,0 +1,35 @@
+import pytest
+from trinity.plugins.eth2.beacon.slot_ticker import (
+    SlotTicker,
+    NewSlotEvent,
+)
+import asyncio
+
+
+@pytest.mark.asyncio
+async def test_slot_ticker_ticking(event_bus, event_loop):
+    slot_ticker = SlotTicker(
+        genesis_slot=0,
+        genesis_time=0,
+        chain=None,
+        event_bus=event_bus,
+    )
+
+    def get_seconds_per_slot():
+        return 1
+
+    # mock get_seconds_per_slot
+    slot_ticker.get_seconds_per_slot = get_seconds_per_slot
+
+    asyncio.ensure_future(slot_ticker.run(), loop=event_loop)
+    await slot_ticker.events.started.wait()
+    try:
+        new_slot_event = await asyncio.wait_for(
+            event_bus.wait_for(NewSlotEvent),
+            timeout=2,
+            loop=event_loop,
+        )
+    except asyncio.TimeoutError:
+        assert False, "Slot not ticking"
+    assert new_slot_event.slot > 0
+    await slot_ticker.cancel()