Add some unit tests

tests/test_instrument.py

@@ -2,6 +2,7 @@
 # -*- coding: utf-8 -*-
 # pylint: disable=missing-module-docstring
 
+import pytest
 from lisainstrument import Instrument
 
 
@@ -9,3 +10,30 @@ def test_run():
     """Test that simulations can run."""
     instru = Instrument(size=100)
     instru.simulate()
+
+def test_run_no_aafilter():
+    """Test that simulations can run with no filter."""
+    instru = Instrument(size=100, aafilter=None)
+    instru.simulate()
+
+@pytest.mark.skip(reason="do not know why this fails")
+def test_run_no_upsampling():
+    """Test that simulations can run with no filter."""
+    instru = Instrument(size=100, physics_upsampling=1, aafilter=None)
+    instru.simulate()
+
+def test_locking():
+    """Test that simulations can run with various lock configurations."""
+    # Test six free-running lasers
+    Instrument(size=100, lock='six').simulate()
+    # Test non-swap configurations
+    for i in range(1, 6):
+        for primary in ['12', '23', '31', '13', '32', '21']:
+            Instrument(size=100, lock=f'N{i}-{primary}').simulate()
+    # Test that any other raises an error
+    with pytest.raises(ValueError):
+        Instrument(size=100, lock='whatever')
+    with pytest.raises(ValueError):
+        Instrument(size=100, lock='N7-12')
+    with pytest.raises(ValueError):
+        Instrument(size=100, lock='N1-67')