Test for errors#

Errors are often encountered in python and they are useful to tell users that they are doing something wrong. pytest allows you to easily test if the correct error is raised.

For instance, let's test initializing a swallow with negative weight:

@pytest.mark.parametrize("species", ["european", "african"])
def test_swallow_negative_cargo_weight(species):
    """Test that cargo weight cannot be negative."""
    swallow = Swallow(species=species)
    with pytest.raises(ValueError):
        swallow.cargo_weight = -1

updated: 2023-04-20