Lock farming pitch downward

tests/test_farming_pitch.py

@@ -0,0 +1,33 @@
+import unittest
+
+from munch import Munch
+
+from mosfet.bot import FARMING_PITCH, pitch_lock_for_job, update_pitch
+
+
+class TestFarmingPitch(unittest.TestCase):
+    def test_only_crop_farming_locks_pitch(self):
+        def farm_crop():
+            pass
+
+        def sleep():
+            pass
+
+        self.assertEqual(
+            pitch_lock_for_job(Munch(state=farm_crop)), FARMING_PITCH)
+        self.assertIsNone(pitch_lock_for_job(Munch(state=sleep)))
+        self.assertIsNone(pitch_lock_for_job(None))
+
+    def test_pitch_is_held_at_45_despite_look_target_changes(self):
+        state = Munch(pitch=0.0)
+        for _ in range(5):
+            update_pitch(state, object(), FARMING_PITCH)
+        self.assertEqual(state.pitch, 45.0)
+
+        # Without the farming lock, ordinary look behavior is restored.
+        update_pitch(state, None)
+        self.assertEqual(state.pitch, 35.0)
+
+
+if __name__ == '__main__':
+    unittest.main()