def test_model_sorts_rows_by_first_name_descending(sakila_connection):
model = TableModel(sakila_connection, table)
model.sort('first_name', 'desc')
row = model[0]
assert row[0] == 11
assert row[1] == 'ZERO'
def test_model_emits_error_signal(sakila_connection):
model = TableModel(sakila_connection, table)
assert model.last_error is None
model.sort('non-existent-column', 'invalid-dir')
assert isinstance(model.last_error, errors.ProgrammingError)
assert len(model) == 0
assert len(model.data) == 0
assert model.loaded_rowcount == 0
assert bool(model.columns) is False