working camera movement

tests/test_camera.py

@@ -0,0 +1,19 @@
+"""Measured producer rate without camera hardware or wall-clock sleeps."""
+import unittest
+from unittest.mock import patch
+from halloween.camera import CameraStream
+
+
+class CameraRateTest(unittest.TestCase):
+    def test_measured_rate_and_stale_frames(self):
+        camera = CameraStream()
+        with patch('halloween.camera.time.monotonic') as clock:
+            clock.return_value = 10.
+            self.assertEqual(camera.status()['fps'], 0)
+            for i in range(60):
+                clock.return_value = 10+i/15
+                camera._publish(b'test')
+            self.assertEqual(camera.status()['fps'], 15.)
+            clock.return_value += 2
+            self.assertEqual(camera.status()['fps'], 0)
+        self.assertEqual(CameraStream(demo=True).status()['target_fps'], 5)