def test_add_single_variable(self):
""" Test that the variable is added correctly to `solver_model`. """
model = ConcreteModel()
opt = SolverFactory("cplex", solver_io="python")
opt._set_instance(model)
self.assertEqual(opt._solver_model.variables.get_num(), 0)
self.assertEqual(opt._solver_model.variables.get_num_binary(), 0)
model.X = Var(within=Binary)
var_interface = opt._solver_model.variables
with unittest.mock.patch.object(
var_interface, "add", wraps=var_interface.add
) as wrapped_add_call, unittest.mock.patch.object(
var_interface, "set_lower_bounds", wraps=var_interface.set_lower_bounds
) as wrapped_lb_call, unittest.mock.patch.object(
var_interface, "set_upper_bounds", wraps=var_interface.set_upper_bounds
) as wrapped_ub_call:
opt._add_var(model.X)
self.assertEqual(wrapped_add_call.call_count, 1)
self.assertEqual(
wrapped_add_call.call_args,
({"lb": [0], "names": ["x1"], "types": ["B"], "ub": [1]},),
)
self.assertFalse(wrapped_lb_call.called)
self.assertFalse(wrapped_ub_call.called)
self.assertEqual(opt._solver_model.variables.get_num(), 1)
self.assertEqual(opt._solver_model.variables.get_num_binary(), 1)
