test for dt

test/unit/test_stepsize.py

@@ -130,3 +130,21 @@ def test_hit_stepsize_max_with_t_stop(time):
     )
     max_stepsize = lambda t: 1 if t >= 1 else None
     assert my_stepsize.adaptive_stepsize["max_stepsize"](time) == max_stepsize(time)
+
+
+@pytest.mark.parametrize("time", [1, 2.5, "coucou", np.array([1, 2]), [1, 2]])
+def test_stepsize_as_value(time):
+    """
+    A test to check that users can pass an int or float to the dt attribute when
+    initialising a F.Simulation class, and an error is raised when passed anything else
+    """
+
+    my_model = festim.Simulation()
+
+    if isinstance(time, (int, float, festim.Stepsize)):
+        my_model.dt = time
+    else:
+        with pytest.raises(
+            TypeError, match="dt must be an int, float, or festim.Stepsize"
+        ):
+            my_model.dt = time