def test_atom_can_get_atom_by_id(self, mock_atoms):
mock_atoms.return_value = {self.atoms[1]}
structure = AtomicStructure(self.atom1, self.atom2, self.atom3)
atom = structure.atom(id=700)
self.assertFalse(mock_atoms.called)
self.assertIs(atom, self.atom3)
atom = structure.atom(500)
self.assertFalse(mock_atoms.called)
self.assertIn(atom, (self.atom1, self.atom2))
self.assertIsNone(structure.atom(id=100))
def test_atom_can_return_none(self, mock_atoms):
structure = AtomicStructure(self.atom1, self.atom2, self.atom3)
mock_atoms.return_value = set()
self.assertIs(structure.atom(element="C"), None)
def test_atom_calls_atoms(self, mock_atoms):
mock_atoms.return_value = {self.atoms[0]}
structure = AtomicStructure(self.atom1, self.atom2, self.atom3)
atom = structure.atom(fufu=500, element="A")
mock_atoms.assert_called_with(fufu=500, element="A")
self.assertIs(atom, self.atom1)