if stirring is paused, measure rpm should be 0

pioreactor/background_jobs/stirring.py

@@ -282,7 +282,7 @@ def __init__(
         )
 
     def action_to_do_before_od_reading(self):
-        self.set_duty_cycle(0)
+        self.stop_stirring()
 
     def action_to_do_after_od_reading(self):
         self.start_stirring()
@@ -359,6 +359,12 @@ def start_stirring(self) -> None:
         if self.rpm_calculator is not None:
             self.rpm_check_repeated_thread.start()  # .start is idempotent
 
+    def stop_stirring(self) -> None:
+        self.set_duty_cycle(0)  # get momentum to start
+        if self.rpm_calculator is not None:
+            self.measured_rpm = structs.MeasuredRPM(timestamp=current_utc_datetime(), measured_rpm=0)
+            self.rpm_check_repeated_thread.pause()  # .start is idempotent
+
     def kick_stirring(self) -> None:
         self.logger.debug("Kicking stirring")
         self.set_duty_cycle(0)
@@ -433,8 +439,7 @@ def poll_and_update_dc(self, poll_for_seconds: Optional[float] = None) -> None:
         self.set_duty_cycle(self._estimate_duty_cycle)
 
     def on_ready_to_sleeping(self) -> None:
-        self.rpm_check_repeated_thread.pause()
-        self.set_duty_cycle(0.0)
+        self.stop_stirring()
 
     def on_sleeping_to_ready(self) -> None:
         super().on_sleeping_to_ready()

pioreactor/tests/test_stirring.py

@@ -113,6 +113,17 @@ def test_publish_measured_rpm() -> None:
         assert message is not None
         assert json.loads(message.payload)["measured_rpm"] == 0
 
+        publish(f"pioreactor/{unit}/{exp}/stirring/$state/set", "sleeping")
+        pause()
+        pause()
+        pause()
+        assert st.state == st.SLEEPING
+        assert st.duty_cycle == 0
+        assert st.measured_rpm.measured_rpm == 0
+        message = subscribe(f"pioreactor/{unit}/{exp}/stirring/measured_rpm", timeout=3)
+        assert message is not None
+        assert json.loads(message.payload)["measured_rpm"] == 0
+
 
 def test_rpm_isnt_updated_if_there_is_no_rpm_measurement() -> None:
     exp = "test_publish_measured_rpm"